Flat roof dimensions. Flat roof: device, materials, installation

IN Lately There is a clear trend towards installing flat roofs. They are persistently replacing the usual gable structures, giving the exterior of the building a more stylish and laconic look. The installation technology and flat blood device have their own characteristics. In this article we will tell you in detail how to make a flat roof with your own hands or choose the best option for your home.

If earlier projects of flat-roof houses were common only in the West and Europe, today more and more Russians prefer this option. Gradually, the standards of classical construction are becoming a thing of the past, and people are choosing more practical and economical technologies. This is exactly what a flat roof is. Its structure is such that installation requires much less financial and time costs compared to a gable roof.

Typically, flat roof designs can be found on country houses or rich cottages, but implementing such an idea is not such an expensive undertaking.

A flat roof consists of several layers:

• base (reinforced concrete slab, metal profile structure);
• vapor barrier (bitumen or roll materials);
• thermal insulation (mineral wool or polystyrene foam boards, expanded clay, cement screed);
• waterproofing (bitumen-based roll materials, PVC membranes or various mastics).

Depending on the type of roof (more on this below) and design features, the order of the layers may vary. The insulation and waterproofing method are selected depending on the base used.

Roof slope

During the construction of a flat roof, it is imperative to ensure its slope from 1 to 4 degrees. Thus, it will be possible to avoid the accumulation of rain and melt water on the surface, thereby reducing the risk of corrosion, leaks, and damage to roofing materials.

The outer covering of the roof will very quickly become unusable if the accumulated water freezes and thaws on it repeatedly. To organize the slope of the roof, materials are selected depending on the technical characteristics of the structure.

The most popular material for this purpose is a lightweight concrete mixture containing extruded polystyrene. It is quite easy to lay it, even without professional skills, and the hardened material has exceptional strength and durability. However, the use of this mixture should be taken into account at the building design stage, since concrete will place a strong load on load-bearing elements and floors.

An alternative option is a concrete mixture with expanded clay or perlite. It costs much less than polystyrene, but is heavier, so the roofing pie will be less durable.

The slope can also be organized using monolithic thermal insulation. To do this, lay sheet insulation on a surface prepared in advance and fix it with glue to prevent the slightest movement over time. It is recommended to use not only glue, but to “fix” the effect with dowels with plastic spacers to prevent contact metal elements with the base of the roof (potential places for the appearance of cold bridges).

The most difficult way to create roof slopes is to use bulk materials, since pouring concrete into a layer of expanded clay, for example, will be quite difficult, taking into account the fact that a certain angle of inclination must be maintained. However, the result is a very strong and durable coating.

Another effective method The leveling consists of laying foam concrete blocks and covering them with fiber-reinforced concrete. This thermal insulation of the pie will last without overhaul for more than a decade, however, the cost of materials and the specifics of installation will require significant financial costs.

Roofing units

For high-quality protection of the roofing pie from the destructive influences of the environment, attention should be paid to Special attention points of its connection with walls, pipes, ventilation and other building elements. The main task of the catch is to ensure the tightness of the joints and their thermal insulation.

The units are organized on a reinforced concrete base at the junction of the roofing pie cut with the vertical structures. For many large manufacturers There are our own systems for creating nodes that take into account the design features of materials.

Types of flat roofing

Before you decide to install a flat roof, you need to choose the most suitable option. There are several types of flat roofs depending on the functional load or design features. So, in the first case, roofs can be used or not.

According to the design features of the roof there are:

• traditional;
• inversion;
• breathable;
• green.

A flat roof allows you to use the roof space as an additional usable area, which is actively used in residential and industrial construction. On such a roof you can make a garden, an open area for relaxation, games, even build a swimming pool or parking lot. In order to build a durable and strong roof, you should understand the types of functional organization and select the appropriate elements of the roofing pie.

Unused flat roof

The unexploited type is the most common. If you look at a cross-section of such a roof, you can clearly see that it consists of several layers, each of which is responsible for the load-bearing capacity of the structure. Distinctive Features non-exploitable roofs are low construction costs and relatively simple installation.

To build a practical and inexpensive roof today, PVC membranes are mainly used, since they can be used in almost any weather conditions. Even if the thermal insulation layer absorbs moisture during installation, the membrane will quickly remove it. Installation of membranes into a monolithic sheet is carried out using welding equipment without open flame.

An unused roof can also be covered with bitumen mastic, applied in an even layer over the thermal insulation. It is made on the basis of polyurethane water-repellent resins. After application, the mastic quickly polymerizes and forms a cast rubber-like coating that is resistant to moisture and mechanical damage.

The most popular way to organize this type of roof is built-up waterproofing. This is an inexpensive technology that provides long-lasting moisture protection for 20 years or longer. Bitumen-polymer coating is produced in the form of rolls, which are rolled out on the roof and secured by heating with welding equipment with open flame. The same method is used for the construction of exploitable roofs.

Operated roof

The construction of a serviceable roof will require much greater financial and time costs, but as a result you will receive additional usable space.

Today, exploited roofs are becoming increasingly popular, especially in densely populated cities. They can be used to build restaurants, parking lots, create parks and sports grounds, saving space on the ground.

SNiP requires that this type of roof can withstand uneven heavy loads and not deform over the entire area. If you look at such a roof in cross-section, you can find a number of significant differences from the unused type. The main one is the presence of a special rigid screed over the waterproofing layer. It eliminates deformation (punching) of the protective coating and its subsequent destruction.

Traditional roofing

Traditional roofs are structures in which waterproofing is located on top of a heat-insulating layer, being at the same time a finishing coating in contact with external environment. This is the most common type and can be seen on almost every modern flat roof structure. And if previously roofing felt was used for waterproofing, today PVC membranes are the best option.

Important: Traditional roofing cannot be used because it is not equipped with a reinforcing concrete screed. In the process of arranging a traditional roof, basalt wool is used, which cannot withstand constant loads.

Advantages of the traditional type of roof:

• simplicity and high speed of installation;
• low cost;
• the opportunity to make a flat roof with your own hands.

One of the disadvantages is the fact that the waterproofing coating must be completely replaced or repaired from time to time.

Roof installation

Technology for creating traditional flat roof It’s quite simple, so even an inexperienced craftsman or a hardworking owner who wants to save money on hiring a work team can handle it.

How the installation works:

1. Prepare the foundation - lay floor slabs or organize a monolithic foundation from a reinforced concrete slab.
2. Lay a vapor barrier - for this it is recommended to use film polyethylene or polypropylene materials, bitumen or polymer roll materials. The latest fused products have advantages over film products - they are denser and thicker, and when fused, no seams are formed through which moisture can penetrate.
3. Lay thermal insulation - thermal insulation material should be selected taking into account the climate and functional features of the structure. For example, for a bathhouse it is better to lay several layers of material to better retain heat inside. The most popular material for this purpose is mineral wool. It has all the necessary characteristics and is inexpensive.
4. Thermal insulation material can be fixed mechanically or by adhesive. In the first case, telescopic dowels are used, in the second, bitumen adhesive is used. The method of fastening the thermal insulation determines the method of subsequent fixation of the waterproofing. If you used dowels, then the waterproofing should be fixed with them, and vice versa. Experts recommend using bitumen for fastening only if we are talking about installation on concrete base. If you use a polymer-bitumen vapor barrier, it is better to secure everything with dowels.
5. Lay the bottom layer of waterproofing - to do this, roll the material over the surface and attach the strips with an overlap of 15-20 cm, after which they are welded using a fire or non-fire method.
6. Lay the top layer of waterproofing - the second layer increases the reliability and durability of the roofing pie. To do this, the rolled material is fused over the entire area of ​​the roll, and not just along the edges, as is the case with the bottom layer.

Inversion roofing

Recently, conscientious owners prefer to install inversion roofs due to their durability and better reliability compared to traditional ones. While conventional roofs begin to leak after a few years, inverted roofs remain intact for decades.

If you look at the structure in cross-section, the difference from a traditional roof lies mostly in the change in the order of the layers. It is this factor that determines high quality pirogue. Moreover, such a roof can be built on an already constructed building. To do this, you just need to dismantle the top layers and then lay out the insulation in the required sequence.

An inversion roof, unlike a traditional one, can be used. It can be used to organize various corporate meetings, create a comfortable summer studio in the fresh air, playground or hold a banquet.

There are several types of inversion roofs depending on the degree of load:

1. Minimum loads - the design consists of steam, heat and waterproofing, as well as a lightweight finishing coating made of rolled material. It can be used in private homes as a summer area.
2. Medium loads (above household level) - thicker and more durable thermal insulation materials are used, the finishing coating is paving slabs or other material with similar characteristics.
3. High loads - on such a roof you can build restaurants, car parks, hold concerts, etc. Intermediate reinforced materials are installed between the main insulating layers; the outer covering is a reinforced concrete slab.

Installation of inversion roofing

Depending on the expected load, the method of installing the inversion roof is selected. Let's consider the general aspects of arranging this type of roof.

Installation stages of inversion roofing:

Breathable roof

The formation of condensation between the insulating layers of the roof has always been a problem, especially for residents of Russia, where changes in temperature and humidity are observed annually. Condensation is formed due to a strong difference in temperature between the outside and inside of the building. Accumulating in a porous or soft thermal insulation layer, it quickly reduces the protective characteristics of the roof. As a result, smudges, cracks, bubbles and other unsightly formations appear on the ceiling inside the house.

The outer covering of the roof also suffers, especially in the summer, when accumulated moisture is actively evaporating. Lack of ventilation ultimately leads to the roof covering simply peeling off from the base.

The so-called breathable or ventilated roof allows you to get rid of this problem forever. Through special holes, moisture evaporates freely from the internal insulating layers. Roof aerators are installed on the surface, placing 1 piece each. approximately 40-50 sq. m.

Advantages of a “breathing” roof:

1. There is no need to dismantle the already installed flooring for installation. The usual old coating is fused by welding, thereby enhancing the waterproof properties.
2. The second layer of waterproofing, fused over the old coating, levels the surface and ensures high-quality outflow of moisture, since it is laid with a slight slope.
3. Certain financial costs for organizing a roof ventilation system are fully recouped within several years.

The principle of operation of the ventilation system

Condensation can completely damage a building within a few years, so it is important to organize the correct and careful installation of the ventilation system. Roof aerators are special fans attached to pipes of various lengths and diameters made of plastic or metal. The fans are covered on top with umbrella-like caps to prevent moisture from entering them from outside.

The aerator operates due to the pressure difference between the outside and the inside. Warm air currents coming from below collide with cold air from the street, thereby driving the fans. Thus, the moisture is independently “blown out” from the roofing pie.

On conventional flat roofs with a simple configuration ventilation holes are located evenly over the entire surface at the highest points and at the junction of heat-insulating elements ( mineral wool slabs). Ideally, installation of ventilation should be carried out during the process of laying the roofing pie, otherwise the costs of its installation will increase.

Interesting fact: Western builders actively use natural smoke removal systems when organizing “breathable” roofs. They allow you to safely leave the building during a fire.

Green roof

We have left the most interesting way to construct a flat roof for last. Green roof is original way acquire your own “piece of nature” in the middle of the urban area. This is a separate direction in landscape design and architecture has already gained popularity in the East and West, where people living in megacities experience an acute lack of green spaces. Gradually, the trends of greening roofs are becoming popular in local latitudes.

Advantages of green roofs:

• saving space - on the roof you can make a place to relax among the greenery, a golf course, grow useful crops (spices, berries, some vegetables);
• the ability to create the most comfortable relaxation area;
• an additional source of pure oxygen in the city;
• plants absorb nitrates and toxins floating in polluted city air;
• the fertile soil layer on the roof cools the interior of the building in the summer and protects from the cold in the winter;
• ensuring almost 100% sound insulation of the room.

Important: When arranging such a roof, it should be taken into account that even a very thin layer of soil creates a noticeable load on the roof, so it is recommended to strengthen the structure or calculate the maximum permissible load.

There are two types of green roofing:

The impressive thickness of the fertile layer dictates certain requirements for the degree of rigidity and reliability of the foundation. Load-bearing structures must support not only the weight of the earth, but also the weight of plants planted in it, furniture installed in the improvised garden and people who will relax there. To this should be added the weight of water, which can make the soil heavier during rains.

Green roof installation

The technology for installing a green roof is, by and large, no different from the construction of a conventional flat roof with increased load. A layer of waterproofing is laid on top of the reinforced concrete base, and extruded polystyrene foam is poured on top, which serves as reliable protection from the cold. Next, lay a layer of geotextile and carry out drainage, covering the surface with crushed stone or gravel. Then they cover it with another layer of geotextile, fill it with soil and begin planting plants.

Important: special attention should be paid to the drainage system. To do this, it is necessary to arrange the roof at a slope so that water can flow down freely. If there is no slope, then such a drainage system must be created artificially. Otherwise, the water will stagnate, which will lead to waterlogging of the soil and damage to the roofing pie.

If you organize a green roof system correctly, you can create a full-fledged garden or vegetable garden right in the middle of an urban area. We invite you to take a look at the options for arranging a green flat roof (photo):

Green roofs not only allow you to better arrange your own leisure time, but also improve the atmospheric environment in a densely populated city. For example, in Japan, for this purpose, all available free areas are specially covered with grass and trees. They also actively use technology vertical growing different cultures, turning concrete facades into fantastically beautiful houses.

If you also want to contribute to the restoration of the Earth's ozone layer, green roofing is your option.

Many people associate a flat roof with urban high-rise buildings. And very few people picture in their imagination a country house with a flat roof, which combines saving precious space and the possibility of creating luxurious places for relaxation on the roof.

Flat roof pie.

In the age of modern building materials and new technologies, it is possible to successfully build private houses with a flat roof, without fear of the surprises of our unpredictable climate. But the full extent of pleasure from a flat roof can only be experienced when the builders and the customer himself listen carefully to the advice of a specialist in installation technology and the selection of the necessary components of the roof structure. Only under such conditions will a flat roof serve for a long time for more than one generation of the inhabitants of the house, without requiring additional costs.

What are the advantages of flat roof designs?

Until recently, various structures and parts for the device were either very expensive or not reliable and functional enough, which did not at all benefit the popularization of roofs of this type, especially for private developers.

However, life experience proves that, being under the influence of stereotypes, we are too biased towards many problems, as a result of which we do not always judge things objectively. The main thing is from many existing options choose the most adequate and correct one to avoid mistakes.

According to architects, buildings in the spirit of constructivism, which brings a minimum of details and simplicity of design, are now becoming fashionable again. As a consequence, in better side The attitude of customers towards flat roofing is changing. In Europe the design flat covering houses is called a fashionable architectural feature of the project. A house with a roof without slopes looks more modern.

Until recently, a flat roof was a complete taboo for most consumers. According to some, it was simply tasteless, others were afraid of heavy precipitation in the form of snow, and still others believed that a flat roof was an undertaking that required prohibitive financial costs. Nevertheless, experts cite a lot of obvious advantages for buildings with this design:

1. In most cases, a flat roof is equipped as green zone recreation.
2. Saving material, because the area of ​​​​the flat coating less area pitched with the same architectural basis.
3. Laying a flat roof is much more convenient than a pitched roof - it is easier to install the covering under your feet rather than in an unsafe position at a high altitude.
4. Maintaining flat roofs is not an extreme mountaineering activity, but rather a routine procedure.
5. Plus, the design of flat roofs makes it possible to obtain additional space without increasing the outline of the structure.

By the way, in developed countries, the possibility of using a flat roof is most relevant in megacities. Here, the problem of ecology has increasingly come to the fore, and therefore raising elements of gardens, parks, vegetable gardens and lawns from the ground to the clouds has become a very popular thing. And most importantly, if you want your flat roof to provide reliable protection, it must be installed correctly using durable modern building materials.

Components of a flat roof

Typically, a flat roof is based on a load-bearing base (it can be a reinforced concrete slab or profiled metal sheet), on which heat-insulating material is laid over a vapor barrier layer, which is protected from precipitation by a waterproofing layer.

It is characteristic that all components of the roofing “pie” are of equal importance, and if at least one of them is unsuitable, the entire structure will be damaged. The basis of the work on installing a flat roof is an integrated approach, which consists in determining the type of coating and implementing the best constructive solution when considering all operational and technological properties, such as fire resistance, water resistance, ease of maintenance, labor costs during installation, aesthetic qualities, etc.

Specialists pay special attention to sealing seams, choosing fastening methods and elements, arranging technological components of the coating (junctions to parapets and pipes, drains, corners, superstructures, etc.) and making through holes. And it goes without saying that the operation of the roof will not depend on any damaging factors if the various components of the structure are made of impact-resistant and weather-resistant materials that are resistant to corrosion processes and exposure to UV rays. Exclusion of at least one detail from common system is fraught with the most undesirable consequences.

Depending on the type of waterproofing, it can be glued, mechanically secured, or loosely laid. Much attention should be paid to the quality of fasteners and the method of their installation, especially for materials that are laid to the base of the roof with mechanical fastening.

If the rules for laying roofing are neglected, the following undesirable consequences may occur:

1. Breakdown of waterproofing by strong gusts of wind.
2. A loss bearing capacity foundations due to electrochemical corrosion in the “incorrect screw + corrugated sheet” system.
3. A clogged or frozen funnel, causing the roof to fill with moisture and leaks.

The roofing “pie” consists of the following layers (from bottom to top):

1. Vapor barrier.
2. Insulation.
3. Waterproofing.

Insulation of a flat roof

Types of flat roof insulation: one, two and three layers.

The base of a flat roof is a load-bearing slab made of monolith, reinforced concrete or corrugated metal sheet. On top it is covered with a vapor barrier material, which protects the insulation from water vapor, thus preventing it from swelling from getting wet and ensuring the preservation of all properties. After this, thermal insulation is installed on the roof, which, in turn, is covered with a waterproofing carpet to protect it from precipitation.

For a flat roof, there are one- and two-layer thermal insulation systems. Nowadays, a two-layer system is more often used in construction. It works like this: the bottom layer, 70-200 mm thick, is assigned the main function of thermal insulation, while the top layer, which is 30-50 mm, is responsible for the redistribution of mechanical loads. Despite the smaller thickness, the second layer is more durable and has a higher density. This distribution of flat roof covering layers makes it possible to significantly reduce its weight and, thereby, the load on the floors. The insulation must meet the following requirements:

1. Low thermal conductivity and water absorption.
2. Fire safety.
3. High vapor permeability.
4. Compressive and peel strength of layers.

Drainage device

It is very important to ensure the free escape of wet vapors from the roofing. Necessary elements are ventilation accessories. As a result of human activity, water vapor is continuously generated inside the building. Due to the convective process and diffusion, it rises upward and, when cooled, condenses in the space under the roof. This process is especially intense in winter. It negatively affects both wood and metal. If too much condensation accumulates, then condensation will form on the ceiling. wet spots and mold develops. In addition, moisture accumulating in the thermal insulation material reduces its properties, which leads to increased costs for heating the room. To avoid such situations, you need to take care of the proper removal of moisture from the outside of the building.

This task is best accomplished by special roofing components - a roof fan, otherwise called an aerator. The aerator consists of pipes of different diameters made of plastic or metal, which are covered with umbrella-shaped caps.

The operation of the aerator is based on the pressure difference caused by the flow of air masses. Its design allows moisture vapor to be removed from under the roofing without damaging the latter.

On flat roofs, aerators are placed evenly over the entire surface at the highest points of the roof plane at the joints thermal insulation boards together. It is advisable to install aerators at the same time as the roof itself. Otherwise, the cost of installing ventilation increases significantly.

There are a large number of components for installing a flat roof. The need for their use is determined. For example, in Western countries, much attention is paid to equipping roofs with natural smoke removal devices, which enable people to safely leave the building in the event of a fire.

The reliability of the roof also depends on its slope. There are no completely flat roofs, because to drain water you need, albeit a very small, slope. For a flat roof it is measured as a percentage.

It is not advisable to install roofs with a slope of less than 2 percent. The best option is a slope of 2.5 percent. In this case, the structure is freed from water in a short time, providing more comfortable conditions functioning of roofing material. WITH good slope even a small defect in the roofing will be insignificant.

Another important element of the roof is gutters, which “carry away” moisture and snow along a given route. This is most often done on a flat roof. Special fittings or fittings located on the roof surface effectively drain water during heavy rainfalls, eliminating flooding of the roof. Their location and quantity must be determined taking into account the design rules for these structures and construction requirements for the design of drains and sewerage systems for buildings. The required number of funnels on the roof depends on its operating conditions, architecture and amount of precipitation. The funnel comes with a special filter that protects the drain from foreign objects getting into it. To prevent the water in the drain from freezing, the mouths of the funnels are equipped with special thermal cables, which guarantees rapid drainage of water at any time of the year.

More often used as in private homes

You can build a flat roof yourself or with the help of specialists. Thanks to this design, the building has a beautiful and stylish look.

Flat roof installation?

The technology of constructing a flat roof is more practical and economical. The installation of such a roof takes less time, as well as monetary costs, compared to a gable roof.

For a flat roof, several layers are used:

• As a base, a reinforced concrete slab or a metal profile structure is laid.
• Then roll or roll materials are used bitumen type, which serve as a vapor barrier.
• After this, polystyrene foam boards, expanded clay are laid, or cement screed, these materials have thermal insulation properties.
• Thanks to the use of PVC membranes or other roll-type materials, it is possible to create high-quality waterproofing.

The layers can be laid in different orders, depending on the type of flat roof. The choice of insulation and waterproofing material depends on the type of base used.

How to properly pitch a roof?

When constructing a flat roof, be sure to make a slope, it can be up to 4 degrees, this is done in order to avoid accumulation atmospheric water. If this is not done, the coating will quickly deteriorate, leaks or corrosion of the surface material will appear. To make the slope, use a mixture of concrete and polystyrene; after laying, it hardens and is durable. Also, instead of polystyrene, you can use expanded clay; such a mixture will be economical, but will place a significant load on the load-bearing elements, and the strength of the roof pie will decrease. Another slope can be achieved using thermal insulation monolithic type. Insulation in the form of sheets is attached to the surface using glue, and then fixed with dowels that have plastic spacers, so the material will not move. The slope can be achieved by laying foam concrete, but this method is expensive.

Types of flat roof

Flat roofs are divided into exploitable and non-exploitable structures, so first you need to decide which type of roof to choose. An unused roof includes several layers that are responsible for the load-bearing function of the roof. This type of design is more economical and easier to install. To construct such a roof, you can use special PVC membranes; their installation does not depend on weather conditions, and is carried out using a welding machine without open flame. You can also use bitumen-based mastic, which is applied on top thermal insulation material. This mastic hardens quickly, resulting in a cast coating resembling rubber, which is resistant to moisture and damage. The polymer-bitumen coating can be in the form of rolls; they are spread on the surface and fixed using a welding machine that has an open flame.

To build a used roof, it will take more time and money, but in the end it turns out additional area, which can be used for various purposes. Such a roof must withstand significant loads and not subsequently deform. Unlike the first option, a rigid screed is placed over the waterproofing material, which prevents the coating from being pressed and deformed.

Based on design features, roofs are divided into the following types:

• traditional;
• breathable;
• inversion;
• green.

Installation technology for traditional flat roofing

The traditional type of roofing are those structures where the waterproofing material is laid on top of the thermal insulation; it also serves as the final covering; for this you can use either roofing felt or a PVC membrane. The traditional type of roof cannot be used, since it does not have a special concrete screed, which has a strengthening effect. When constructing the structure, basalt wool is used, but it cannot withstand loads. This roof has its advantages:

• quick and simple construction;
• efficiency;
• All the work can be done independently, without the help of specialists.

The disadvantage is the fact that the waterproofing material will have to be repaired or replaced over time.

Roof installation is carried out in the following sequence:

1. First, the foundation is installed; for this, floor slabs or a monolithic reinforced concrete slab are used.
2. Then they begin installation vapor barrier material, it can be polyethylene, bitumen or polymer. The latter type of vapor barrier is denser and stronger than other materials; during fusing there are no seams into which moisture can penetrate over time.
3. Thermal insulation is laid, for this you can use mineral wool, it is more economical and retains heat well.
4. Fix the thermal insulation material using bitumen glue or dowels.
5. Then they begin laying the lower part of the waterproofing material, the rolls are spread on the surface with an overlap of up to 20 centimeters, and fixed by welding.
6. On top, another waterproofing layer is laid, which serves to protect the entire structure and ensure its reliability. The fusing of the top waterproofing rolls is carried out over the entire surface, and not just at the joints, as in the first case.

Inversion flat roof installation technology

The inversion type of roofing is more reliable and durable than a traditional roof; it does not leak for several decades.

When constructing this type of structure, the order of the layers changes, which improves the quality of the roof. Unlike the first method, such a structure can be operated.

• For minimal loads, foam-insulating, heat-insulating, and waterproofing materials are used. Roll-type materials are used as the final coating.
• For medium loads it is necessary to use stronger and denser thermal insulation. Paving slabs or other types of similar material are used as the final covering.
• For significant loads, reinforced material is installed between the main layers of insulation. And as a final coating, a reinforced concrete slab is used.

Installation of an inversion flat roof is carried out in the following sequence:

1. First, prepare the base, lay a reinforced concrete slab, then cover it with a primer so that the built-up waterproofing adheres well.
2. Laying waterproofing material is slightly different from traditional method. First, waterproof material is laid, it can be PVC or rolls containing bitumen.
3. Then they begin laying the insulating material.
4. Then geotextiles are laid out, which should be located between the insulating materials. internal composition, and final coating.
5. At the end, the final covering is laid; for roofs with minimal load, roll-type materials or crushed stone are used, which are applied to the entire surface. For a roof with an average load, you can lay paving slabs or use other durable materials. For significant loads, use a monolithic reinforced concrete slab.

Breathable flat roof installation technology

The breathable type of roof prevents the accumulation of moisture inside the structure; thanks to this type of structure, this space is well ventilated. There are no leaks, cracks, or other problems on the ceilings due to the formation of mold. Through the holes made from the inner layers of insulation, moisture can freely evaporate and escape outside. Special aerators are placed on the roof surface, 40 square meters One piece is enough.

A breathable roof can be made as follows:

1. There is no need to remove the installed cake; it is enough to strengthen the waterproofing function. Using a welding machine, fuse the old coating.
2. A new layer of waterproofing material is fused on top of the previous coating, then the entire surface is leveled and moisture is removed.
3. Accumulated condensate can completely destroy a building within a certain period of time, so it is necessary to provide the roof with a high-quality ventilation system. To do this, install special aerators that serve as fans; they are fixed to pipes made of plastic or metal. The devices are covered from above with caps in the form of umbrellas, so that outside no moisture got into them.
4. The operating principle of the aerator is based on different internal and external pressures. Warm air from below comes into contact with the cold flow, and the fans begin to work, and the humidity under the roof disappears on its own.
5. On a simple flat roof, such holes are placed at the highest point, at the connection there is heat insulating materials. Fans are installed during the installation of the roof; if this is done after the work is completed, then unnecessary costs may be incurred.

What is a green roof and how to build it?

Green roofing allows you to give the building an original look and design. This roof has a number of advantages:

• By saving space, you can grow various vegetables and berries, ornamental plants on the roof, and create a comfortable area for relaxation or business meetings in a green atmosphere.
• With the help of plants, more oxygen appears on the site, that is, they have a beneficial effect on the environment. Plants are also capable of absorbing various toxic substances if the city is heavily polluted.
• The layer of soil located on the roof cools the room inside in summer period, and insulates the room in winter.
• Thanks to this structure, the level of sound insulation increases.

If you plan to build such a roof, then you need to strengthen the structure, since a significant load will be placed on it.

Green roofing can be of two types:

The extensive type of roof is covered only with ornamental plants or lawns, while the soil layer is up to 15 centimeters. Watering is carried out only when the grass begins to grow and other plants are placed in pots. At the same time, lawns are trimmed periodically, as needed.

The intensive type of roof allows the placement of soil up to 60 centimeters, that is, you can plant not only decorative, but also fruit plants that have shallow roots. A garden or vegetable garden can be placed on a roof of this type, and the load-bearing structures must withstand significant loads. This type of roofing is expensive.

Installation of a green roof is carried out according to the principle of a conventional reinforced structure. First, a reinforced concrete base is laid, then waterproofing material is placed. After this, polystyrene foam is laid, it serves as an insulating material. Geotextiles are laid out and drainage is made from crushed stone or gravel. Then the geotextiles are laid again and the soil placement begins. After all the layers have been laid, the necessary plants can be planted.

They construct such a roof at a slight slope so that excess water can flow down without hindrance. Otherwise, it is necessary to install a drainage system, otherwise in case of stagnation of water, the roof pie will deteriorate. Moisture will begin to penetrate into the room, this can lead to the destruction of the flow, and subsequently the walls.

Thanks to this solution, the roof can be given an original look, and various vegetable and fruit plants can be usefully grown. Among such an atmosphere, you can create a play complex for children, an area for relaxation, tea drinking, and other events.

When installing a green roof, water should not be allowed to stagnate on the surface. It is better to plant plants that do not require frequent watering. You also need to take into account the load exerted by the soil located on top; the structure must be reinforced to withstand the entire expected weight. It is advisable to make all calculations before work on the construction of the roof begins.

Conclusion

Before you start installing a flat roof, you need to decide whether it will be used in the future or not. Traditional look a flat roof is considered more economical option, and installation does not take much time. The inversion type of structure is stronger and more durable and does not require replacement of the final coating for several decades. By constructing a breathable roof, you can easily get rid of moisture using special fans, this allows you to extend the life of the insulating materials. Green roofs give the building an original look and save space for growing various plants.

Flat roof installation, installation technology

Installation of a flat roof requires the presence of a roofing “pie”. It has high heat-shielding properties that prevent the attic from overheating in the summer and allow it to retain heat in the winter.

Installation technology and installation of flat roofs

All urban multi-storey and industrial buildings are houses with flat roofs. Moreover, today many who love the modern style in architecture prefer to have a flat roof in their private homes. It really looks stylish, but, among other things, houses with such a roof are more functional - you can build a winter garden on them or use the roof as a recreation area in the warm season. Therefore, we immediately move on to describing the stages of installing a flat roof and consider its structure in detail.

Flat roofing is great for those who use it as an open floor.

Subtleties of installation and design of the roofing “pie”

Installation of a flat roof requires the presence of a roofing “pie”. It has high heat-shielding properties that prevent the attic from overheating in the summer and allow it to retain heat in the winter. In addition, the roofing “pie” can prevent the formation of condensation, the insulation will be protected from moisture, and ice and icicles will not appear on the roof. It is important to observe its correct design.

The design of the roofing “pie” involves the presence of several layers:

• load-bearing base;
• vapor insulation layer;
• multilayer insulation;
• water protection.

Scheme of a flat roof.

Installation of the roof should begin with preparing the base. It needs to be leveled, cleaned, and cracks in the concrete filled with polyurethane sealant, based on a consumption of 180 g per 1 linear meter with a joint width of 5 cm and a depth of 0.3 cm. The next stage is priming using an epoxy primer. On porous surfaces you will need 0.2 kg per 1 sq.m., on non-porous surfaces - 0.12 kg. The primer is mixed with a low-speed mixer until a homogeneous mass is obtained, after which it is diluted by ½ with water. Apply to the surface with a paint roller or brush. After all of the above, the surface of the base can be reinforced. For this purpose, special mastic is applied (14 kg per 1 cubic meter). Before polymerization, a construction bandage is placed on it, and after polymerization, another layer of mastic is placed.

Any roof needs a vapor barrier. For this purpose, polypropylene and polyethylene films, which are fastened with nails or binders or glued. In this case, you need to maintain a 10 cm gap for ventilation so that steam does not accumulate under the film. Thermal insulation material must adhere tightly to the roof surface, pipes and ventilation units.

Roof insulation and thermal insulation materials

Insulation is responsible for maintaining warmth and comfort in the house. Properly selected thermal insulation materials will not only bring comfort to its walls, but will also allow significant savings on heating. Therefore, you should always pay attention to such qualities of roof insulation as low thermal conductivity, fire safety, vapor permeability, which is necessary for good ventilation of the room; resistance to moisture and various mechanical damage.

Stages of laying roofing felt on the crawl.

It is very important that the material from which the insulation is made is resistant to point loads. In 80% of cases of roof damage, they are the cause of many problems. The main ones:

• violation of waterproofing, as a result of which moisture reaches the roofing “pie” and destroys it;
• causing serious damage during a thaw due to snow freezing;
• the appearance of “cold bridges” that increase heat loss.

To protect the roof from such troubles, you need to ensure that the roof insulation occurs in accordance with all rules and regulations of construction, and you also need to control the quality of the materials used. One of the most common materials without which thermal insulation and roof insulation is indispensable is stone wool. It is very easy to install and can withstand temperatures of 1000 °C. In addition, polyurethane foam, foam concrete, foam glass and extruded polystyrene foam are often used as roofing thermal insulation materials. Let's take a closer look at each type of material.

Thickness of various roof insulation materials.

Polyurethane foam (PPU) is highly technological and has additional waterproofing properties. However, it cannot be left as a finishing coating, since exposure of polyurethane foam to ultraviolet radiation will make it fragile and reduce its service life; insulation is its main purpose. But this material has good maintainability and can be easily repaired locally. For 1 cubic meter you will need 60-80 kg of polyurethane foam. This amount is due to the fact that polyurethane foam is prone to burning, but its use in this particular ratio reduces its combustible qualities. When exposed to direct fire, the polyurethane foam melts, and when the source of fire is eliminated, it instantly extinguishes.

Foam concrete has more high coefficient thermal conductivity in comparison with polyurethane foam, therefore reliable insulation will be obtained if its thickness and material costs are higher, on average, 250 kg per 1 cubic meter. However, this increases the load on the roof above.

Extruded polystyrene foam is a thermal insulation board material. Insulation with its use has become very widespread and is very popular due to its ease of installation. The slabs are laid tightly over the entire surface and glued together, after which the roof is considered fully insulated.

Thermal insulation using stone wool implies an identical installation method to the previous one. The difference lies in the material itself. Stone wool slabs usually have two densities. The side with increased density is often marked with a black stripe. It is this side that the slab should face up.

Foam glass is laid on a flat, dry surface, filled with molten bitumen. Foam glass blocks are placed at a certain distance from adjacent blocks and moved diagonally towards them. To fix the position of the slab and remove excess bitumen from under it, you need to press the middle with your foot. Foam glass is highly durable, resistant to high temperatures and many acids, and has low thermal conductivity, which ensures maximum insulation. However, its high cost often makes it less attractive for use as a thermal insulation material.

Roof waterproofing can be done in many ways, but the most popular of them is bitumen. Let's stop there. Bitumen mastic stir with a drill with an attachment for 5 minutes. The first layer is made more liquid than subsequent ones. It is applied with a density of 90-120 g per 1 sq. cm. The next layer of bitumen is applied after the previous one has dried, after about 10-12 hours. The more layers there are, the higher the protection.

Features of a flat roof device

The design of flat roofs divides them into exploitable, non-exploitable, inversion and traditional. The design of an inversion roof differs in that the thermal insulation layer is located above the waterproofing, and not under it. This allows you to protect it from ultraviolet radiation, mechanical damage, and temperature changes. An unused roof does not imply additional use of the roof; its installation is most affordable. An exploitable roof requires active use of the roof surface (the presence of a sports or helipad, a cafe). In this regard, its installation is more expensive than the installation of unused roofs, but also more durable.

Despite the fact that the roof is called flat, it still has a slight slope (1-4%). This design allows precipitation to disappear on its own. The device of any roofing structure must withstand a load of 200 kg per 1 sq.m., its own weight and the weight of the roof covering. Therefore, they lay it on durable reinforced concrete slabs 4-5 cm wide and 40 x 40 cm in size to increase reliability.

Installation of a flat roof: installation of a roofing pie, thermal insulation

Installation of a flat roof has its own installation characteristics. You need to clearly determine for yourself whether the roof will be used or not, and choose a material for thermal insulation.

Flat roof construction: technologies and materials

A flat roof has a smaller area than a pitched roof, and for this reason alone it is cheaper. Money is also saved due to the absence truss structure, and roll waterproofing materials themselves are less expensive than tiles or metal.

For domestic private housing construction, flat roofs are not typical. Many homeowners consider them to be attributes of industrial architecture and high-rise buildings. However, as soon as you move a little further west, for example, to Poland, cottages with flat roofs appear in large numbers. And this is not surprising, because the Poles are the closest neighbors of the Germans, and they know a lot about saving. In Germany there really is a huge number of private houses of post-war construction with a flat roof.

Recovering from the devastation, the Germans were forced to count every penny. And although houses with flat roofs were not traditional for them at that time, they began to build them. It was primarily the economic advantages that had an impact. Construction time was also reduced due to less complex and labor-intensive installation.

There are also functional advantages of flat roofs. First of all, this is the rational use of the space of the upper floor, due to the absence of inclined slopes. Additionally, the horizontal design of the roof makes it easier to inspect and repair. A flat roof can be made usable: arrange something like a terrace there, place air conditioning units or supply and exhaust ventilation units.

As for the climatic factor, the only limitation for building a flat roof may be regions where heavy snowfalls are typical. There it is better to have a pointed pitched roof, like you see in the Alps.

Flat roof technology

Whatever the shape of the roof, its function does not change: providing protection to the building from precipitation and thermal protection. However, the simplicity of constructing flat roofs is only apparent. With the slightest deviation from the technology for creating a flat roofing cake, you can easily get mold on the ceiling, leaks and other troubles.

Thus, special attention should be paid to strength load-bearing structure, since in winter snow loads can be much higher than on non-pitched roofs. The water resistance of the coating is no less important, because... he will have to cope with heavy rainfall and heavy snowmelt. In addition, the roof structure must withstand high temperatures, at the same time, without collapsing or deforming.

In private houses, there are living spaces directly under the flat roof, so the thermal insulation of the roof must be impeccable.

A flat roof, unlike a pitched roof, is not characterized by windage. There are practically no wind loads on it, which cannot be said about snow loads. The snow cap on flat roofs can form quite large and heavy, while remaining there for a long time. On the one hand, this is a significant load, on the other, additional thermal insulation. If the flat roof is in good condition and good quality, then experts recommend not removing snow from it.

A flat roof is not horizontal. It either has a slope of at least 1.5-2.5%, or is shaped like a funnel. On exploited roofs, a minimum slope is created, but on ordinary roofs it is better to create a larger slope - about 3-10%. If the slope of a flat roof is more than 10%, then it becomes a pitched roof. The distribution of slopes of flat roofs is influenced by their size. So, if the width of the house is more than 10 m, it is recommended to tilt it in two directions from the central axis.

The base of a flat roof is ceiling last floor. Such a roof is called a roofless roof. This design, subject to proper design and use of modern heat- waterproofing materials, will last no less than a good pitched roof.

As a ceiling, you can use structures made of wooden, metal I-beams or reinforced concrete beams, as well as reinforced concrete slabs. Moreover, unlike the usual interfloor slab, the roof slab is calculated taking into account the increased snow load.

Beam floors must be designed with a slope of at least 7-10%. If such a slope is too large, then you should choose concrete floors (prefabricated or monolithic). The latter will withstand any load, but will require a more powerful foundation and fairly strong walls.

The method of ensuring the required roof slope should be determined in advance. Sometimes it is created using different heights opposite external walls. In other cases, a concrete or expanded clay concrete slope-forming screed is installed.

Today, special roofing corrugated sheeting is often used for the base of a flat roof, which differs from the wall sheeting by the higher height of the ribs and increased thickness of the metal.

Flat roof design

The design of a traditional flat roof includes several layers, in particular, steam, heat, and waterproofing. The lowest layer is a vapor barrier, located directly on the ceiling and protects the insulation from the diffusion of water vapor from below. Thick polyethylene or polypropylene film, laid in overlapping strips across the slope, is most often used as a vapor barrier material. Some people install foil vapor barrier, hoping that the foil will reflect thermal radiation back, but this is only possible if there is a gap between the foil and the base, and in this case there is none. In addition, aluminum foil quickly collapses when in contact with the alkaline environment of a concrete screed. Thus, the use of foil vapor barrier does not provide any advantages.

Immediately above the vapor barrier there is insulation. On flat roofs, experts recommend using basalt wool, which has high fire-fighting characteristics. Two layers of slabs are used: the first is the main insulating layer 7-20 cm thick; the second is a 4-5 cm layer of high-density slabs, designed to evenly distribute the load. Roll insulation is not used on flat roofs - only slabs!

If the insulation is placed on top of the corrugated board, then the long side of the slabs should be perpendicular to its ribs, the space between which is filled to the top with non-combustible material. This filling eliminates blowing in the thickness of the sub-base.

Waterproofing is laid on top of the insulation. The installation method depends on its type. The waterproofing layer can be made with special mastics, rolled materials, or a combination of both.

For a long time, roofing felt was used as a finishing coating for flat roofs. Today, this obsolete material has been replaced by built-up bitumen waterproofing (euroroofing material). The new material turned out to be much more practical than its predecessor. Manufacturers give a 15-year guarantee for euroroofing felt, but in reality it can last much longer. It can only be threatened by mechanical damage such as punctures, etc. However, today this is not the only finishing coating for flat roofs.

Most experts prefer roofing membranes - single-layer polymer materials. There are two main types of roofing membranes. One of them is represented by PVC material, durable and reliable, which will last on a flat roof for 25-40 years. Second type - TPO membranes, made from thermoplastic olefins and reinforced with polyester or glass fibers. The service life of such membranes is considerable - 50-80 years.

A useful property of roofing membranes is the ability to pass vapor molecules from the inside to the outside. This allows you to keep the insulation dry, even if it is moistened. Roofing membranes are laid in one layer, simultaneously serving as both waterproofing and finishing roofing.

Strips of roofing membrane sheets are sealed using a special roller soldering iron, which provides heating up to 170°C. The edges of the membranes are inserted onto the parapet at least 15 cm and attached to its walls using self-tapping screws or glue. The edge of the membrane is covered with a profile drape.

It's important to understand that roofing membranes, for all their advantages, are not intended for constant load. You can walk on them in shoes with soft soles, but only if necessary.

Modern bitumen roll materials cope better with mechanical loads, however, they are not intended for intensive use. To make it possible to walk on the roof, it is necessary to lay a special covering (for example, a terrace) or install inversion roofs, where the waterproofing is additionally protected by extruded polystyrene slabs.

The cost of a membrane flat roof is higher than roofing using roll bitumen materials. However, in the long term, membranes are more profitable (especially TPO), because their service life is several times longer.

Flat roof construction: technologies and materials

Flat roof construction: technologies and materials A flat roof has a smaller area than a pitched roof, and for this reason alone it is cheaper. Money is also saved due to the absence

Until recently, a flat roof was considered the prerogative of monotonous urban high-rise buildings and industrial buildings. Now the situation has changed. More and more private developers are resorting to this architectural solution, trying to increase the usable area of ​​the house by installing a terrace or observation deck on the roof. Great prospect, isn't it?

But it can also become a real headache if the elements of a flat roof are selected or positioned incorrectly, in violation of the technologies recommended by experts. To avoid getting into trouble, let’s understand the structures of flat roofs, their components and the layer-by-layer distribution of elements.

Let's start with the basics. In fact, a flat roof only visually gives the impression of absolute horizontality. There is still a slight slope - 1-5° (1.7-8.7%). Visually and during operation, it is completely imperceptible, but it allows precipitation to flow freely to the drainage points - this is its main task.

Unlike pitched analogues, a flat roof does not have a rafter frame and, in fact, is a horizontal ceiling resting on the walls of the building. Its peculiarity is in the reinforced layers of thermal and waterproofing, necessary due to the communication of the roof with the environment.

The attractiveness of flat roofing for developers is justified by the following advantages:

1. Reduced price. Compared to a pitched roof, a flat analogue has a smaller area, and therefore the cost of materials is lower.
2. Simplified installation and further maintenance. Arranging a flat structure is simpler than a pitched structure, since it is easier to move along a horizontal plane than on an inclined one. For the same reason, various maintenance activities for the roof itself and the devices located on it (chimneys, fans, antennas, etc.) are not difficult.
3. Possibility of obtaining additional usable space(with a roof in use). The surface of a flat roof can easily be used as a terrace, a walking area and even... a garden with a real lawn.

The main element of a flat roof is a solid base: reinforced concrete slabs, corrugated sheets or a solid surface made of boards, plywood, OSB, DSP (when the roof is equipped according to wooden beams). The roof covering itself is made of several layers. Their number, location in the structure and materials of manufacture depend on the purpose of the roof and its type.

Types of flat roofs:

• Unused roof. The simplest one, which does not carry any additional functions other than protecting the premises from environmental influences. It is not used for arranging places for recreational or economic purposes. All that is required of it is a sufficient protective function, the ability to withstand snow and wind loads, as well as the weight of workers carrying out maintenance activities. That is, when constructing such a roof, the calculation is made that 1-2 people can be on it at the same time, and not permanently, but only during maintenance and repair of the roof.
• Operated roof. It is equipped to perform some additional functions other than roofing itself. For example, sports grounds, terraces, parking lots are built on exploited roofs, lawns are planted, and flower beds are planted.
• Inversion roofing. It is characterized by an unconventional placement of layers - thermal insulation mats (EPS) are laid almost at the very top of the cake. Waterproofing is installed under a layer of insulation. This solution helps to extend the service life of the waterproofing coating, and, accordingly, the roof itself. Inversion roofs can be either used (most often) or not used.

Flat roof pie structure

Each type of flat roof has its own design features that allow the use of specific materials and placement of layers in a certain sequence.

Unexploited classic roof

Finishing layer of this type roofing is a waterproofing coating: roofing felt, bituminous built-up materials, polymer membranes, roofing mastic. Such a roof is not designed for long-term occupancy and operation, and therefore the presence of a waterproofing layer is not provided.

It is also not necessary to use thermal insulation. Depending on the presence of this layer, unused roofs are divided into insulated and non-insulated.

An insulated roof contains in its structure a heat-insulating layer, protected by a vapor barrier (from the base) and waterproofing (from the outside). Due to the presence of insulation, this type of roofing is used in the construction of many residential, civil and industrial buildings.

The layers of insulated, non-exploitable roofing are placed in the following sequence (the pattern may vary slightly):

• base;
• vapor barrier;
• insulation;
• waterproofing ( roof covering).

The basis of an insulated non-exploitable roof is most often reinforced concrete slabs or a metal profile, less often - a base made of boards, OSB, DSP, plywood on wooden beams. If necessary, the base is supplemented with a slope-forming layer, which sets the direction of water flow from the roof. The slope is formed, as a rule, with bulk materials, screed (concrete or expanded clay concrete).

A vapor barrier layer is installed on the base arranged in this way, which is used to protect the insulation from wet steam rising upward from the side of the room. Polyethylene and polypropylene films, glassine, and roofing felt can be used as a vapor barrier. Next come 1-2 layers of insulating materials (mineral wool, polystyrene foam, EPS), and on top of them - a waterproofing carpet made of bitumen materials or polymer membranes.

Uninsulated unused roof is formed in a similar way, minus two layers - thermal insulation and vapor barrier, which in this option Not needed.

Roofing layers used:

• base;
• slope-forming layer (if necessary);
• roofing covering.

Operable classic roof

More complex design. It differs from the previous version in the presence of a durable upper layer, which serves to equip the operating site. As a rule, paving slabs, decking boards, gravel or crushed stone filling are used for this.

A serviceable roof can be installed both above the garage and above residential building. Accordingly, this design can be insulated or non-insulated.

Common structure of the pie of an insulated roof in use:

• base;
• slope-forming layer (if necessary);
• vapor barrier;
• insulation;
• waterproofing;
• separating and filtering layer (geotextile);
• paving slabs for preparation.

One of the options for installing an insulated serviceable roof (with a detailed analysis of all elements) is shown in the video:

An uninsulated roof in use does not contain thermal insulation. Respectively, vapor barrier film to protect the insulation is also not used here. Otherwise, the structure is identical to the option discussed above.

Inversion roofing

This is a special case of exploited and unexploited insulated roofs. In a classic roofing structure, the insulation is always covered with a waterproofing barrier on top.

In an inversion roof, the layers are reversed. Waterproofing membrane moves under the heat insulator. If in an ordinary classic roof a waterproofing carpet protects the insulation, then in an inversion “reversal” it’s the other way around. The thermal insulation layer protects the waterproofing.

This solution allows us to bypass one significant drawback of traditional roofing structures: the rapid destruction of the waterproofing carpet from the influence of temperature changes, ultraviolet rays, atmospheric influences. Inversion roofs do not have this drawback; in their structure, the service life of the waterproofing carpet is much longer.

The layers of an inversion type flat roof are placed in the following order:

• base;
• slope-forming layer (if necessary);
• waterproofing;
• insulation;
• drainage layer;
• geotextiles;
• protective finishing layer - crushed stone or gravel ballast, tiles, terrace board and etc.

The installation of an inversion roof is carried out according to the following principle. First, a waterproofing barrier is laid on the base and covered with insulation. Next comes drainage and geotextiles. Upper layer performs a protective function; it is often made in bulk.

The structure of the inversion roof does not use a vapor barrier. Accordingly, the insulation may suffer from steam coming from the side interior spaces. The insulation on top is also not covered by anything from precipitation (in traditional roofs, the protection function is performed by waterproofing, which in this version is hidden in the bottom layer of the pie). Therefore, the insulation is required special requirements, first of all, minimal water and vapor absorption. Extruded polystyrene foam (EPS) mats have these characteristics - they are most often used in the structure of inversion roofs.

The stages of installing an inversion roof are shown in a training video from URSA:

Arrangement of a drainage system

As mentioned earlier, a flat roof is not completely horizontal; it is characterized by a slight slope (up to 5°), which is used to construct a drainage system.

The slope is formed in several ways:

• If the base of the roof is a reinforced concrete slab, then the slope is carried out using backfill materials (expanded clay, crushed stone, perlite), concrete and expanded clay concrete screed, and insulating slabs.
• If the roof is built on wooden beams, then the slope is ensured either by initially laying the beams at a slight angle, or by additional installation of logs of different thicknesses with a slope in the required direction.
• When using profiled metal as a base, its installation is initially carried out at the required slope.

The slope is necessary for the installation of drains, which can be internal and external.

When installing an internal drain, the slope is led to water inlet funnels or fittings located on the roof surface. Their number and location depend on the roof area, its operating conditions, and the amount of precipitation in a particular area. As a rule, one funnel is installed per 200-300 m2 of roofing.

A filter is installed inside each funnel to prevent leaves, branches, and small animals from entering the drain. To prevent water from freezing, some models of funnels are equipped with self-regulating thermal cables. They facilitate the unhindered removal of atmospheric moisture even in winter, during thaws.

Internal drainage is usually used for large industrial buildings. In private construction, external drainage systems have become more widespread. In this case, the slope is directed from the center of the roof to the edges, and drainage holes (overflow windows) are installed at the corners of the parapet along with storm drains. It is recommended to supplement such a system with heating cables, since in winter there is a possibility of icing of storm drains and overflow windows.

Flat roof ventilation elements

Inside the premises where people live or work, water vapor constantly accumulates. It rises to the ceiling, cools, condenses and accumulates in the under-roof space. Moisture has a destructive effect on all layers of the roof - wood, metal and concrete. And when it accumulates in the insulation, it gradually reduces its properties, increasing heating costs.

In order for wet vapors to escape from the roof structure, they are installed on a flat roof. ventilation devices– aerators. They are plastic or metal pipes of different diameters, covered on top with caps in the form of umbrellas.

On flat roofs, aerators are placed evenly over the entire area. It is recommended to install them at the highest points of the plane, where the insulation boards join. Usually, the installation of aerators is carried out during roof construction, but it is also possible to do this during repairs. The main thing is that this measure will greatly increase the durability of the roof and insulating material.

In conclusion, I would like to note that all elements of the roof are equally important for its subsequent operation and, even if just one of them turns out to be unsuitable or missing, the entire layer-by-layer structure will suffer. Therefore, the choice of the type and quality of the roofing pie package must be taken with full responsibility.

The choice of one design or another largely determines the possibility of using the attic as an additional living space, resolves the issue of the need for insulation and determines the type of roofing covering.

A flat roof is a specific option that does not allow the attic to be equipped as a living space (due to its absence).

But it offers a lot of possibilities for using the territory as an auxiliary site, a place for placing equipment or as a private recreation area, separate from the external space.

A flat roof can provide many interesting possibilities in this regard, but there are limitations to its use.

The main feature of a flat roof is its almost horizontal surface. such surfaces are low - up to 8 degrees, it is needed only for drainage of rain or melt water.

According to the conditions of the plane's location, there is practically zero wind load (if properly constructed without overhanging edges) with a maximum snow load.

Wherein, the roof structure has a complex multi-layer structure, ensuring the tightness of the coating and the working condition of the insulation.

Most favorable conditions operation of flat roofs:

• Small amounts of snow in winter. It is most suitable for use in regions with warm or little snowy winters, when removing snow from the roof does not cause difficulties.
• Wind force does not have a significant effect on the roof, therefore, the construction of such roofs in areas with strong or gusty winds is permissible.

For areas with cold and snowy winters, the use of flat roofs is only recommended for small commercial buildings having a relatively small area.

The use of flat roofs on residential buildings is more common in southern regions, where there is no problem with high snow pressure in winter.

Flat roof

The structure of the roofing pie

There is no specific, classic composition of the roofing pie of a flat roof. Layer structure most often based on the following factors:

• Roof purpose;
• Floor type;
• Roofing material.

The decisive factor that determines the composition of the roof from the very beginning of construction is the purpose of the roof. It depends on it what material is needed for the construction of the floor, how exactly it will be insulated, and what kind of optimal material coverings.

Insulation of a flat roof made of soft roofing is done from the outside, since this method is much more convenient and reliable in terms of the tightness of the cake.

The general insulation technology looks like this:

• Base (concrete, wooden floor);
• Vapor barrier film;
• A layer of insulation;
• Top layer of waterproofing;
• Roofing.

This is the general plan, in practice it is often supplemented or complicated with the aim of more reliable protection from water penetration or the formation of cold bridges.

Roofing pie

One of the options for installing a flat roof is inversion roofing. This is relative the new kind pie designs that take into account the disadvantages of conventional options.

The fact is that a common problem with flat roofs is water seeping through the insulation into the ceiling and the appearance of stains and streaks.

To eliminate this phenomenon, inversion roofing is used when A reliable waterproofing carpet (often multi-layered) is installed between the ceiling and the insulation..

The composition of the pie is built as follows:

• Overlap;
• The waterproofing preparation layer is usually a construction primer;
• Waterproofing carpet;
• Geotextile layer;
• Insulation (optimally extruded polystyrene foam);
• Top layer of geotextile;
• Ballast fill layer of gravel.

If necessary, a rigid covering can be laid on top of the ballast layer to maintain uniform ballast thickness and ease of movement.

Inversion roofing cake

Is the roof based on wood or concrete?

Wood or concrete can be used as a base for a flat roof. Both options are acceptable, but not interchangeable.

So, wooden base used for small buildings, most often for economic purposes.

If there is no heating, then such a roof is not insulated, a simple rafter system is made and the roofing covering is laid on top. However, wooden floors are also used for residential buildings.

This is due to the desire to lighten the roof and remove excess load from the walls (for example, with the frame construction method).

CAREFULLY!

This option imposes certain restrictions on the functionality of the roof, excluding the presence of heavy equipment, a large number of people, etc. on it.

More often, for the roofs of residential buildings used, a concrete slab is used as a base. This overlap has a number of significant advantages:

• Reliability;
• No noticeable deformation from loads;
• Penetration of moisture into the material will not cause rotting;
• Finishing a concrete floor is easier than finishing a wooden one.

Since it is produced outside, the lower surface of the concrete floor (the ceiling of the upper floor) will be open, which allows you to use any available type of finishing - from simple painting to installing a stretch ceiling.

If the ceiling is made of wood (beams), then the finishing should be done taking into account possible deformation - “sagging” of the ceiling due to existing loads.

Sectional photo of the roof basics:

Wooden base

Concrete base

Flat roofs: arrangement of private houses

The composition of the roofing cake is never chosen at random. The main selection criterion is general purpose roofs:

• Lightweight. The roof serves only as protection from precipitation. Mainly used for auxiliary buildings for utility purposes;
• Exploited. Such a roof serves as a platform for placing various equipment, for creating recreation areas, small greenhouses, swimming pools, etc.;
• Green. On such a roof there is a lawn with grass, plants, etc. Serves as a mini-square for relaxation.

Depending on the purpose of the roof, the type of ceiling is selected, which, in turn, largely determines the optimal type of roofing material. Therefore, the composition of the roofing cake may have its own individual characteristics.

So, for a flat roof of an outbuilding it will be enough:

• Rafters;
• Lathing;
• Roofing covering (metal profile, etc.).

Lightweight roof

For a used roof, which is used as a platform for installation solar panels, satellite television dishes or other equipment, the composition is much more complex:

• Concrete floor slab;
• Cement screed that forms a slope for water drainage;
• Waterproofing layer;
• Drainage material that removes water from under the upper layers;
• Insulation layer;
• Geotextile layer;
• Sand preparation layer;
• Paving slabs.

In this case, the outer covering is paving slabs, as a durable and cheap material.

ATTENTION!

At the same time, rain or melt water can quite easily penetrate the insulation layer, so it must be resistant to moisture, impermeable to water, or, as an option, painlessly pass water through the drainage layer to the drain.

Operable roof

Pie diagram for creating a green roof:

• Concrete floor slab;
• Layer ;
• Multilayer waterproofing carpet;
• Insulation;
• . It consists of a separating layer of reinforced screed, a double layer of technoplast (EPP and Green), and a geodrainage roll layer;
• Layer of soil with plantings.

In this case, there is a multi-stage waterproofing system that reliably cuts off the insulation material from the top soil layer. This cutoff, at first glance, is too complicated, necessary to guarantee the creation of a reliable barrier to water.

The soil is an active accumulator of moisture, which will certainly seep into the lower layers, so the complexity of the composition of the pie is fully justified.

Green roof

How to cover a flat roof

The material for covering a flat roof is selected based on its purpose.

Unused surfaces are most often covered with roofing felt and the joints are sealed with liquid bitumen.

Recently it has appeared large quantity similar materials with improved characteristics that make it possible to more reliably protect the roofing pie.

Operated surfaces require a tougher and more durable coating. At the same time, the task of hermetically sealing the insulation from external influences is not removed, so most often a sand-cement cushion and a working layer - paving slabs - are laid on top of the soft roof.

Coating

Installation of a used flat roof

How to make a flat roof? First of all, you need to decide on the basic parameters - type of roof, structure, etc. Let's consider the option of installing an exploitable flat roof with concrete floor and external drainage using gutters:

1. The surface of the floor is covered with a layer of slope-forming concrete screed (slope). To save concrete, a layer of gravel is first poured on a slope, after which a screed is laid on top. Since this stage refers to “wet” work, then It is recommended to cover the surface of the ceiling with a layer of primer or similar material.
2. Laying vapor-waterproofing. As a material, you can use various fused films or roll membranes. Laying with overlap, seal the joints with tape.
3. Insulation layer. Either stone mineral wool or extruded polystyrene foam is used. The insulation is laid in several layers, minimum 2 layers. This requirement is caused by the need to prevent the penetration of cold through cracks in the joints of the insulation.
4. On top of the insulating layer a layer of waterproofing is laid.
5. Filling the ballast layer - gravel, sand, etc.. The role of this layer is double: protecting the film coating and draining water coming from melting snow or precipitation in the summer.
6. On top of the ballast layer if necessary, a layer of paving slabs can be laid for ease of walking on the surface. In this case, you will need an additional sandy preparatory layer, a direct substrate for the tiles.

The indicated sequence is one of the options; there are many similar methods that are equivalent in results, but differ in details.

The installation of a flat roof, traditionally considered an accessory of auxiliary buildings, can be carried out in such a way that the roof surface turns into an additional platform that can be used for various needs.

Depending on the climatic conditions of the area, the surface of a flat roof is turned into a green lawn, a technical area for placing equipment, or a recreation area.

All roofing options require careful arrangement and expensive materials. The quality of the result directly depends on the qualifications of the people performing the work and on the financial capabilities of the home owner.

But don't forget that you can build a flat roof with your own hands.

Investments in an equipped, usable flat roof will only be worthwhile in regions with short, mild winters and low average monthly precipitation. All other issues can be resolved and serious problems they don't call.

Waterproofing

Insulation

Useful video

In this video you will learn what the structure of a flat roof made of fused materials is:

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