Roof heating: how to prevent roof icing? Heating of roofs and gutters: technology for installing an anti-icing system Using self-regulating cables.

From the article you will learn what cable heating of roofs and gutters using anti-icing systems is, the main components, installation rules, types and structures of cables, laying diagram and principle, how to connect, control and protection equipment, ready-made solutions and much more.

Main tasks of anti-icing systems

Anti-icing systems are a set of devices whose task is to prevent the formation of ice on the eaves, as well as ice plugs in drains for draining water.

Timely and correct installation of roof heating and gutters helps protect building construction from dangerous contact with water, snow accumulations or the formation of icicles.

The main difficulty is the correct arrangement of the system, because the quality of heating and the efficiency of the system as a whole depend on this.

What is a roof and gutter heating system?

An anti-icing system is also called a cable heating system for gutters and roofs.

Its work is based on laying a group of cables that heat up and help melt snow, and also protect against the formation of ice on the roof and in the building's drainpipe.

The peculiarity of the system is the possibility of its inclusion in the most dangerous periods when roof water is most likely to freeze.

It is known that main reason Damage to roofs, gutters and gutters is caused by ice, which accumulates on the surface and has a destructive effect.

At correct installation The cable system prevents icicles from falling near the house, which makes it possible to classify it as one of the elements of the building’s security system.

In 2004, the Moskomarkhitektura issued a document that provided recommendations for the installation of such systems on the roofs of buildings equipped with internal and external drains. Such recommendations applied to both residential buildings and industrial facilities.

Today, heating of roofs and gutters is in greatest demand in Moscow and St. Petersburg. In these cities, anti-icing systems are installed on several thousand buildings, and this number is only growing.

During the period of installation work, companies that specialize in this work managed to accumulate considerable experience and eliminate serious mistakes that were made previously.

With proper design and compliance with installation rules, the cable heating system eliminates the appearance of ice on the surface and guarantees timely drainage of water through the devices intended for this purpose.

Thanks to this, the service life of the roof increases significantly, and “punching” and deformation of the gutters are eliminated.

In addition, the risk of icicles falling on people passing by buildings is reduced.

Causes of roof icing

Experts identify two reasons for the formation of ice on the roof of structures:

How does ice dam affect the roof and roofing material?

If the angle of the roof is less than 45 degrees, in winter a “cap” of snow mass will form on it.

In some cases, the weight of snow can reach 100 kg per square meter. The load increases even more if the roof has a slope of 30 degrees.

In such cases, the rafters may become deformed under the weight of the snow. To avoid this problem, it is important to periodically clear the roof of snow and remove icicles. Heating the roof and gutters helps solve this issue.

If you save on the anti-icing system, the consequences may be as follows:

• Roof deformation. During the period of snow melting, the ice crust that forms on the surface is heated from below, moves and damages roofing material. In the future, corrosion processes begin from these scratches.
• Damage to the drain. Weather conditions are unpredictable. There are situations in nature when, after a short thaw, frost comes again. As a result, the water accumulated in the gutters freezes, which leads to deformation or rupture of these systems.
• Collapse of icicles, melting of snow mass. If heating of the roof and gutters is not provided, the time of fall of the accumulated mass of snow or icicles cannot be predicted. As a result, there is a high risk of injury to passing people, including injuries that are not life-threatening.

What types of roofs are there?

Taking into account the thermal regime, all roofs can be divided into several types:

A heating system for the roof and gutters will get rid of the problem, but its installation is associated with many difficulties, and its operation requires large amounts of electrical energy.

For this reason, it is better to perform the work in several stages. First, the amount of “extraneous” heat is reduced by insulating the upper floors, and then an anti-icing system is installed.

If there are under the roof heating systems, they need to be additionally insulated.

Main components of the anti-icing system

The roof and gutter heating device consists of the following elements:

One or more heating cable branches. The installation pattern is determined taking into account the type of roofing structure required, the level of complexity of the surface, and the presence or absence of a water drainage structure.

General installation rules

Before installing the icing system, it is important to draw up the project in advance, and then begin installation work.

The documentation must take into account the following points:

• PUE requirements;
• Recommendations from the manufacturer of the system and its elements;
• Decree on implementation fire protection measures;
• Other documents.

The best results when installing an anti-icing system can be obtained by following following rules:

• Work on a fine day when no precipitation is expected;
• The icing system must be installed only at above-zero temperatures;
• The area intended for laying the heating element must be clean and dry.

remember, that most of sealants and adhesives that are used during the installation process operate at above-zero temperatures.

The same conditions apply to various models of power and heating cables.

During the installation process, consider a number of other recommendations:

• For maximum efficiency of the anti-icing system, perform work in the warm season.
• Installation of roof heating and gutters is best done on roofs where an organized drainage system is provided.
• The purpose of such a system is to prevent melt water from freezing and ensure that accumulated moisture is drained into the drainage system.
• Before starting work, the roof surface must be cleaned and dried.

The ideal option is when the anti-icing system is designed at the building design stage.

In this case, it is worth considering the laying route in advance. power cable from the roof structure assembly to the energy distribution point.

If a heating system for the roof and gutters was not provided, horizontal and vertical embedded parts must be installed during the construction process.

When installing an anti-icing circuit, the cable power supply should be covered using rigid boxes or corrugated channels.

Types and structures of heating cables

When arranging circuits, two types of heating products are used, the total power of which is equal to or greater than 20 W per square meter.

Gasketing is usually done open method, therefore, the cables must have a reliable sheath that protects from UV rays and atmospheric moisture.

During operation heating elements should not touch materials containing bitumen - euro-roofing felt, flexible tiles and other coatings. If the installation is carried out on a bitumen roof, the cable sheath must be made using photopolymer.

A big plus is the presence of an armored braid that will protect the product from mechanical damage.

On sale you can find power cables that are made in the form of a spring and prevent rupture due to expansion or physical influence.

Resistive cable - types and structure

When installing an anti-icing system, two types of resistive cables can be used - single and two-core.

In general, the product consists of a metal conductor that generates heat, shielded braiding, insulation, and an outer PVC sheath.

Let's take a closer look at the types:

Resistive cables allow you to save on heating the roof and gutters at the stage of purchasing the material. As for installation, it is more expensive because it requires a longer length. The number of fasteners also increases.

The disadvantage of resistive cables is that they have a fixed length of sections, while the main elements of the roof, gutters and gutters are made of different lengths.

The problem can be solved in only one way - by selecting products with different resistances. In addition, the operating conditions of different sections of the cable may vary, which is why roof heating is not always effective.

Self-regulating cable - types, structure and typical layout diagrams

Unlike a resistive product, a self-regulating cable adjusts the resistance in each section or along the entire length. If desired, it can be cut into pieces of suitable length.

Structurally, the self-regulating cable is an electric-type tape heater, inside of which parallel conductors are located.

The latter are separated using a heat-releasing polymer matrix semiconductor type.

In turn, the conductive material of the central part plays the role of a heating element, which allows you to cut the cable in any necessary place.

As a result, the appearance of cold areas is eliminated and heat production is regulated taking into account the characteristics of the environment.

In fact, each section of a self-regulating product quickly adapts to external conditions.

This type of cable can be of two types - with or without copper braiding. Otherwise, the structural elements are identical:

• Copper conductors;
• Self-regulating matrix;
• Polyolefin shell;
• The outer shell is polyolefin type.

As noted above, resistive cable costs less, but energy costs are higher.

At the same time, the use of a self-regulating “competitor” allows you to reduce costs, which is explained by proper adjustment to weather conditions.

Due to the design features, such a cable can heat up differently on different areas of the roof - in the shade or on the illuminated side.

The ability to cut anywhere eliminates a lot of excess.

Most popular brands:

• 30KSTM2-T;
• Freezstop-15;
• Freezstop-25K;
• Defrost Pipe 20;
• Defrost Pipe 40;
• 31FSR-CT and others.

More about self-regulating cables.

Definition of heating zones

When determining working areas and places for laying cables for heating gutters and roofs, the efficiency of drainage of melted water is taken into account.

To achieve the greatest efficiency, the cable is laid in drainpipes ah, gutters and other places where there is a high risk of ice formation.

The total length of the de-icing system is determined by adding up the main roof elements that require heating.

On a steep slope, when there is a risk of snow and ice falling off, it is necessary to install a snow retention system.

In such situations, it is worth laying the cable in the area between protective device and the edge of the roof. The height of the snake is selected taking into account the width of the cornice.

If there is no risk of collapse, you can only heat the gutters and gutters. Depending on the diameter of the latter, the power and quantity of self-regulating cable are selected.

Scheme and features of laying heating cables

The choice of scheme for laying roof heating elements and gutters is made taking into account the angle of inclination of the roof slopes, as well as its configuration.

The greater the slope and simpler form, the fewer meters of product will be required to arrange the surface.

Principles of laying and fixing a heating cable

Anti-icing systems, as a rule, are concentrated in areas of the greatest accumulation of winter precipitation and ice formation.

These include:

IN pitched roof You can do without heating the eaves. If the angle of inclination is more than 45 degrees, the snow mass will be removed without additional help. In this case, the heating cable should only be laid in the elements of the drainage system.

If ice forms near the attic windows, the heating filament is laid near them towards the drain.

If the building does not provide drainage system, the heating line runs along the drip and along one side of the slope.

Here it is necessary to mount a device for retaining snow above the cable installation site and install a drip line on the eaves.

The fastening of the elements of the anti-icing system deserves special attention. Here you should adhere to the following rules:

Installation of an icing system for flat roofs

On a flat roof, the heating cable is laid around the perimeter of the water drain line.

In addition, the heating circuit must be inserted into the internal drain funnel by about 40 cm or more (for an internal drain). If the trays are external, a dripping loop is made.

Where the roof touches the parapet, installation is carried out near a receiving tray with a power of 60-80 W per “square” with exit to the tray and placement in a pipe for water drainage.

Connecting the power cable

The anti-icing system is connected using a power cable to a single-phase or three-phase network.

When connected to a 380V network, phase imbalance in the range of 10-15% is possible. To avoid the problem, it is advisable to use anti-icing systems with a total power of up to 6 kW.

If this parameter is higher, the connection is made evenly to the three phases of a 3-phase circuit.

When choosing a cable cross-section, you should focus on the power consumption and the total length of the heating section. In turn, the power depends on the resistance of the branches and the length of the heating line.

During the installation process, it is important to take into account the PUE regulations. The power and heating cables must be combined in a junction box, instead of which a heat-shrink sleeve can be used. The latter guarantees tightness at the joints.

Installation of an internal drainage heating system

The internal drain, which is heated according to a separate scheme, deserves special attention.

The structure includes a funnel roof, waterproofing, thermal insulation and mounting tape.

The system elements also include a temperature sensor, heating section, distribution box, power cable, casing, clamp and rivet.

If the roof has flat design, and drainage funnels are built-in type, the heating cable is laid along the water collection path, as well as in areas near the funnels.

After this, it is discharged into a funnel and into a pipe until it exits into the heated room.

If the product does not go through a warm area, the heating cable is lowered to the foundation of the structure or to the level of the blind area. In the presence of drainage system laying is carried out to the freezing depth.

Anti-icing system control and protection

The purpose of the control system is to create conditions for automatic or semi-automatic operation of heating the roof and gutters, and the protection system - for quick fix emergency situations (short circuits, leaks or overloads) in the circuit.

Let's consider these points in more detail.

Control equipment

The task of the control equipment is to activate the heating cables, as well as turn off the power when the operating temperatures are exceeded.

Today two types of equipment are used:

The first option is more affordable, but in regions with high humidity there may be a greater error and the appearance of ice on the roof surface.

In this regard, the weather station is better sensitive and responds more accurately to changes in humidity. In addition, the greater accuracy of the weather station allows you to save money on electricity.

If low humidity prevails in the region and the installation requires a low-power anti-icing system, a thermostat will suffice.

Interestingly, self-regulating cables are able to operate without automatic control, thanks to the ability to independently regulate their power taking into account the outside temperature and the presence of precipitation.

But it is better to use special thermostats.

Here you can use the following devices:

Of the weather stations, IS-11 performed well, which is characterized by increased efficiency and does not require cleaning during operation.

Protection equipment

The control and protection panel for the heating system of the roof and gutters includes the following elements:

• Introductory circuit breaker;
• Thermostat (weather station) protection circuit breaker;
• Magnetic switch;
• RCD (30 mA);
• Heating circuit protection circuit breaker;
• Alarm.

In more complex systems, a number of additional devices can be installed, namely a time delay relay, a current transformer, controllers, a soft starter and other systems.

The protection equipment must guarantee:

• Protection of the supply circuit (single-phase or three-phase) from short circuit in the heating line, power cable or in any of the equipment elements;
• Overload current protection;
• Shutdown of the system or one of its sections when a leakage current exceeds 30 mA.

In the first two cases, the protection function is taken over by the RCD, and in the last one, the RCD takes over. You can combine two devices in one - .

Material calculation example

To present the level of costs for installing an anti-icing system, we provide an approximate calculation of materials.

Let's imagine that the hanging gutter is 12 cm wide and semicircular in shape. Its length is 20 meters, and along the edges of the gutter there are a pair of drainpipes with a height of 14 meters and a diameter of 10 cm.

In the calculation process, it is taken into account that the installation is carried out in three lines:

As a result, installation of the system requires:

The total power of the anti-icing system (at a supply voltage of 220 V) is 2.9 kW.

Next stage- selection of protective automation. Here you will need a single-phase RCD with 30 mA leakage and 25A rated current, as well as a single-phase circuit breaker with 16 A.

Fastening is carried out in pipes and gutter using special clamps. The calculation is carried out taking into account 3-4 fastenings per meter of gutter or pipe.

The total length of the mentioned elements is multiplied by 4 and obtained total number fasteners.

For our case, this is 14 m + 14 m + 20 m = 48 m. We multiply the final number by 4 and get 192 fastenings.

You will also need a cable to secure the cable in the water drains. Here the formula is as follows - (Hcable+1 m)*2 = (14+1)*2 = 30 m.

As a result, from additional equipment required:

• Cable in a plastic sheath - 30 m;
• Cable clamp - 2 units;
• Number of clamps - (14 m+14 m)*4 = 112 units.

Features of cable fastening depending on the type of roof are listed below.

How much electricity is consumed?

One of the key factors when choosing an anti-icing system is the amount of electricity consumed. Please note that the equipment's power reserve may not be sufficient to lay the equipment.

Operating costs are determined taking into account the cost of electrical energy consumed during the operation of all elements of the system.

The formula has next view- C year = Pн*h*s.

Its components:

• Cyear - the price it costs to operate the system for a year, rubles;
• Pn - rated power of the system, kW;
• S - price of 1 kW/hour of electrical energy, rubles;
• h is the number of hours the system operates during the year.

To calculate the approximate costs of maintaining the heating of the roof and gutters, it is important to determine the number of hours of its operation.

For this, it is taken into account that the system is active somewhere from November 15 to April 15, that is, 151 days or 3624 hours.

On average, 20% of this time the system is turned off automatically due to lack of precipitation or exit from the operating temperature range.

It turns out that the total number of hours of work is lower. We multiply 3624 by a factor of 0.8 and get 2900 hours.

Below we give an example of the annual cost of maintenance provided that resistive cables with a total length of 100 meters and a power of 3000 W are connected.

Cyear = 3 kW*2900 h*1.05 rub./kW*hour=9.135 thousand rub.

In case of use self-regulating cables Electric energy consumption will be lower by an average of 12-15%.

Rules for operating the anti-icing system

To ensure trouble-free operation and long-term operation of the heating system for the roof and gutters, it is important to strictly follow the installation instructions and trust the work to experienced workers. The latter must undergo the necessary training.

If you do the work yourself in the absence necessary knowledge, there is a high risk of not achieving the expected result.

The basic operating rules include:

• Installation of the anti-icing system should be carried out while it is still warm, before the onset of cold weather;
• The roof and gutters must be cleared of debris, and the system must be inspected twice a month. If a breakdown is detected, you can fix it yourself or involve specialists;
• Cleaning must be done with extreme care to avoid damage to the insulation. Please note that if the integrity of the cable is damaged as a result of mechanical impact, the warranty is lost;
• The settings are set on site, taking into account climatic factors. When independently determining the boundaries of turning on/off the system, you should rely on the manufacturer’s recommendations.

Ready-made solutions on the market

Below we will consider ready-made solutions for anti-icing systems.

Gutter heating kit with Hemstedt cable, 28 meters.

The anti-icing system has a power of 23 W per linear meter. The advantages are resistance to UV rays and ease of installation.

The kit includes 28 meters of cable, which is enough to heat the drain and gutter, having a total length of 14 meters.

The total power is 700 W. Alternative option The application of the anti-icing system is the heating of platforms, steps and paths, pipes and tanks.

Heating cable 104 meters long from the manufacturer Hemstedt (Germany).

The kit is useful for heating drains and gutters with a total length of 52 meters.

Laying is carried out in two routes (between spacer routes). In addition to 104 meters of cable, the kit contains mounting tape.

The total power is 2.388 W. It is used for heating tanks and pipes, gutters and roofs, platforms and paths.

Heating cable from Germany (manufactured by Hemstedt), 44 m.

The anti-icing system has a total length of 44 meters and a power of 23 W/linear meter.

The product is resistant to UV rays, is laid in two routes and has a total power of 2.2 kW.

Scope of application - heating of platforms, paths and steps, gutters and roofs, tanks and pipes.

FS 10 - cable for heating water supply from Hemstedt, 10 meters long.

This device model is ready for use and turns on automatically when the temperature reaches above zero.

The heating cable consists of the following elements - a temperature sensor, a heating “cold” and “hot” conductor, as well as plug.

Fastening is done using clamps to the pipe and subsequent connection to the power supply network.

The rated voltage of the product is 230 Volts, the length of the “cold” cable is 2 meters, the power is 10 W/m.

The characteristics also include an outer diameter of 9 mm, a nominal temperature of 65 degrees Celsius, and a minimum bending radius of 5 times the diameter.

The FS10 cable is excellent for small diameter pipes and can be installed in plastic pipes.

Heating cable Thermo.

It is one of the main elements of the roof and gutters heating system.

The kit also includes mounting tape for fastening to a concrete base, an insulating corrugated tube, as well as instructions in Russian. The cable cross-section is 6.7 mm.

The advantages of the product include protection of the cores with a special screen made of aluminum foil, the presence of additional insulation and cable reinforcement using fiberglass.

The upper temperature limit is 90 degrees Celsius. Power - 20 W per linear meter.

The outer shell is made of PVC. The length of the “cold” wire for connection is 3 meters, and the cross-section is 1.5 square meters. meters.

The entire product range is shown below.

Thermostat ET-02-4550.

This is an excellent solution for controlling your anti-icing system. It can be used to control electric and water heating devices.

The main options include the presence of two control zones, low energy consumption, convenient programming and the presence of an emergency relay.

The device clearly records temperature and humidity parameters. The operating temperature range is from 0 to 5 degrees Celsius. Rated current - 16 A.

Thermostat ETR/F-1447A.

This is a reliable thermostat that is installed in panels using a DIN rail.

The device is used to melt snow and ice on gutters and roofs of small buildings.

It has a remote sensor that monitors the air temperature. Operating temperature range from -15 to +10 degrees Celsius.

Installation can be done manually. The upper load limit is 3.6 kW. Rated current - 16 Amperes.

Thermostat ETV 1991.

A model that is mounted in panels on a special DIN rail. Application is possible for heating the entire room or heating the floor.

One of the areas of application is ensuring the melting of ice and snow on roofs, heating pipelines and protecting external areas.

Features - load up to 3.6 kW, as well as the ability to connect an external temperature sensor.

The operating range is from 0 to +40 degrees Celsius. Rated current - 16 A.

Heating cable from Germany Hemstedt with a length of 16 m.

The product is intended for heating a drain or gutter up to 8 meters in length.

The power is 25 “square” per linear meter. Features include resistance to UV rays and the possibility of laying in two routes.

The total power of the kit is 380 W. The system is controlled manually. Temperature range - from +5 to +40 degrees Celsius.

DEVIsafe 20T two-core cable.

The product is intended for heating roofs, gutters and gutters. It is resistant to UV radiation and precipitation.

Structurally, it has two cores with a screen made of foil and copper braid.

The upper temperature limit is 65 degrees Celsius. The length of the “cold” cable is 2.3 m. Product type is resistive. The cable has a diameter of 6.9 mm.

Cable FS10 36 meters.

Designed for heating gutters. The heating element consists of a plug, a temperature sensor, an electrical cold and hot cable, and 2 meters of cold connection wiring.

The cable is easy to install. It is secured using clamps, and the operating temperature range is from -15 to +5 degrees Celsius.

The system is controlled automatically. Power is supplied from a household network of 220-240 Volts.

Profi Therm cable.

Designed for heating drainpipes and roofs with one core and a power from 23 to 140 W.

This is a Ukrainian-made product, which is supplied with two couplings for each section.

The product is used (except for the purpose already mentioned) for heating steps, parking lots, paths and other structures.

The upper and lower ambient temperatures are +75 and -20 degrees, respectively. Control is carried out automatically. Supply voltage - 220 V.

Cable with thermal limiter, 22 meters long.

The product is based on two cores with photopolymer insulation. The bimetallic thermostat ensures operation at temperatures up to +5 degrees Celsius. Shutdown occurs at +15 degrees Celsius.

The main area of ​​application is heating of water supply pipes. Diameter - 8.2 mm. Maximum operating temperature - + 65 degrees Celsius. The length of the “cold” section is 2 meters. The total power of the set is 220 W.

Cable SMCT-FE 30W/m with two cores and a power of 4 kW from Thermopads (UK).

The power is 30 W per square meter. meter. The main area of ​​application is roof insulation, as well as providing outdoor heating.

The total length is 134 m and its thickness is 6 mm. The advantages include minimal losses and optimal use of heat. Average term service (under warranty) is 10 years.

Two-core cable TXLP/2 R.

Designed for heating roofs and drainpipes with a power of 28 W/meter.

The manufacturer of the product is Norway, Nexans. Scope of application - heating of steps, platforms, gutters, roofs, tanks and pipes.

This type of product is reliably protected from moisture, overheating and UV rays. It is equipped with a coupling-free connection, which guarantees trouble-free operation of the cable at the junction of the power and heating parts of the cable.

The work is carried out automatically. The upper temperature limit is 65 degrees Celsius. Warranty - 2 years.

Hemsted heating cable 19 m long.

Anti-icing system designed for 9 m gutter and downspout. Features include resistance to UV rays and a total power of 460 W.

The cable is laid in two routes. Maximum temperature should be 40 degrees Celsius. Control is carried out manually. The power of the product is 25 W/m.

The benefits of roof and gutter heating systems are difficult to overestimate. They help extend the life of the roof, remove ice, protect against the formation of icicles, improve the performance of drains and reduce the risk of leaks.

In the absence of experience in such work, it is better to involve specialists who know the installation schemes, strictly follow the work technology and configure the system taking into account modern requirements.

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Huge icicles hanging from roofs, ice pillars at the location of drainpipes - this is the picture residents of populated areas are used to seeing in winter. Owners of private houses fight snowdrifts on their own, but in public and multi-storey residential buildings, roof cleaning is done manually by utility workers. As for the icicles, they are knocked down or fall under their own weight, which is very dangerous for passers-by.

Such a fight against snow and ice on roofs causes a lot of trouble for property owners: the roofing covering is damaged; drainage systems become unusable; there is a high probability of injury to people, so it is required. It will not be possible to change the situation from year to year if cable roof heating is not installed - modern system, preventing the accumulation of snow masses and the formation of ice.

Roof heating technology

The technology for creating a roof heating system is not complicated: a thermal cable is fixed to the roof. This includes installing the heating cable on the roof along the elements of the drainage structure and near the valleys (see photo). Falling snow turns into water under the influence of heat and flows down the drain to the ground. All anti-icing systems operate in a temperature range from 5 degrees Celsius to 10 degrees below zero. For this purpose, resistive and self-regulating heating cables are used.

Using resistive cables

The use of resistive cable to provide heating of the roof and heating of gutters is attractive because the cost of its installation and operating costs is low. The work is based on heating a metal conductor due to internal resistance to electric current. The core (one or two) may have one or two layers of insulation and a copper/steel screen.

The advantages of heating a roof with a resistive cable are as follows:

• constant power;
• absence of starting currents;
• acceptable price.

Constant power is also a disadvantage of a resistive cable, since various places roofs require different heat transfer from the cable, but it is constant throughout its entire length. Depending on the degree of icing of individual sections of the roof, it may either overheat or its heat will not be enough.

When roof heating is provided by a resistive cable, it must be regularly monitored so that it is not covered with debris or dry leaves, since it can overheat and eventually burn out. Also, to achieve the required heating power, an accurate calculation of the length of the cable is necessary, since it cannot be cut during the installation process - otherwise the heat transfer will decrease.

Zone resistive cable is considered the best option. The difference in its design is that the conductive cores are protected by an insulating layer, and a nichrome thread is wound on top of it, which acts as a heating element. To create heating zones, this thread is connected at intervals to conductive cores.

Zone resistive cable has other advantages:

• convenient installation;
• availability of linear power, which does not depend on the cable length;
• In the event of damage, only the part of the cable limited to the local area will not function.

Roof heating system, watch the video:

Using self-regulating cables

A roof heating system with the installation of self-regulating cables involves a different heating method, as a result of which the temperature in a separate section of the roof may change and heat generation may decrease/increase.

The operation of this type of cable is based on the presence of a pressed polymer matrix located between two conductive cores, the insulation consists of several layers, and then a copper or steel heat shield follows. Since the self-regulating cable can be up to 150 meters long, it is enough to provide electrical heating for a large roof area.

This heating system has a number of advantages:

• reliable operation;
• energy savings (the cable regulates the amount of heat generated depending on the presence of snow and temperature changes);
• there is no need to clear the roof of debris, branches and leaves;
• since the linear power does not depend on the length of the cable, it can be cut into pieces and mounted on a roof with a complex configuration;
• easy installation.

In addition to its advantages, a self-regulating cable has a number of disadvantages:

• drop in heating power due to aging of the polymer of the pressed matrix;
• higher cost when compared with resistive cables;
• starting currents are approximately 2 times higher than the operating parameters, so installation of such a cable is possible if the building has a reliable power supply. If the region experiences difficult weather conditions during the cold season, a self-regulating cable can be selected only if there are opportunities for sudden changes in power.

Cable anti-icing systems, which are installed on all types of roofs, will help prevent the formation of ice on the eaves and plugs in the drains. They will protect building structures from destructive contact with atmospheric water and protect households from icicles and snow debris.

In order for the system to function without failure, you need to know how to arrange heating of the roof and gutters, how to design and install it.

Device purpose cable system anti-icing of roofs and gutters - preventing the formation of ice build-ups on eaves, in drainage funnels, risers, and gutters.

It is obliged to prevent the formation of icicles and plugs in the drain, as well as ensure the removal melt water V storm sewer or just to the ground. Therefore, if necessary, it also covers the drainage system.

List of main elements

The standard composition of the cable anti-icing system includes:

• One or more heating cable branches. The pattern of its installation is determined by the type of roofing structure, the degree of its complexity and the presence or absence of a drain.
• Power electrical cable. Required to connect a power sibling to a network supplying alternating current with traditional characteristics 220/380 at 50 Hz.
• Protection device. A system that turns off the circuit in whole or in part when leaks through weak insulation points exceed 30 mA and when the permissible load current rating is exceeded.
• Control equipment. A system that starts or stops heating within operating temperatures (standard range from + 5º to – 15º C). Works in automatic and semi-automatic format. The control equipment responds to signals from temperature sensors or temperature sensors coupled with humidity sensors.

The operation of the heating system when the thermometer is below the minus limit leads to what it must fight - the formation of ice in the drain. With warming above the positive limit, it makes no sense to function at all. However, the operating temperature range may be adjusted depending on the climatic conditions of a particular area.

Adjustments are made taking into account a number of weather factors. For example, in areas with high wind activity, the appearance of melt water on system elements and the accompanying likelihood of cable damage occur at lower positive temperatures. In “windy” regions and areas with high humidity it is worth increasing the minus limit, because icing can occur before reaching -15º C.

In fact, the functionality of the heating system for eaves and gutters must respond to the formation of melt water and snowfall. Because It is quite difficult to adjust the atmospheric regime to strict boundaries; objects adapt to the weather data after the fact.

General installation rules

The installation of the anti-icing circuit must be carried out according to a previously created project. IN design development the requirements of the PES, the resolution on compliance with fire safety measures and the recommendations of the manufacturer of the system or its individual components must be taken into account.

An impeccable result of the circuit construction will ensure compliance with the following rules:

• Work on installing anti-icing systems should be carried out only when the thermometer readings are positive.
• To carry out the installation, you should choose a day that does not threaten precipitation.
• The area intended for laying the heating cable must be dry and clean.

Most used in cable installation adhesive compositions and sealants can only be used in positive mode. Similar conditions are required for many models of power cable and for some heating representatives.

Ideally, the possibility of installing a roof heating system with drainage elements should be taken into account during the design of the house. It is necessary to foresee and think through the route for laying the power cable from the energy distribution unit to the roof structure and drainage components.

If the construction of a heating system was not provided for, then vertical and horizontal embedded parts must be installed for the power cable during the construction period. When installing an anti-icing circuit after construction, it is recommended to use rigid boxes or corrugated metal channels under the power cable.

Heating Cable Options

In the construction of ice protection circuits, heating cables are used, the linear power of which is equal to or more than 20 W/m. Because If they are laid mainly in an open way, they must have an external protective shell that prevents the effects of UV rays and atmospheric water.

The external insulation of the majority of heating cables is not allowed to come into contact with materials containing bitumen: flexible tiles, euro-roofing felt, etc. If it is necessary to lay a circuit on a bitumen roof, cables sheathed in a stable fluoropolymer are used.

To protect against mechanical damage, heating cables are equipped with armored braiding. There are offers on the market with a current-carrying element in the form of a spring, which eliminates rupture due to physical impact and linear expansion under positive temperatures.

There are two types of heating cables used in anti-icing systems:

• Resistive cable. Presented with budget single-core and slightly more expensive two-core options. It is produced in the form of sections fixed in length and is characterized by a stable linear resistance. You cannot shorten sections at your discretion, which significantly complicates the design of the system.
• Self-regulating cable. It reacts sensitively to changes in weather conditions, following which it independently adjusts the linear resistance along the entire length or in certain areas. It can be cut into pieces of the length required for arrangement.

The first of these options is cheaper and structurally simpler. The resistive type supplies heat with one or two wires. Due to constant resistance readings, its use complicates design and installation.

In case of insufficient power, for example, it is increased by laying an additional line. Crossing resistive branches is not allowed. To prevent fire, the cable should be regularly cleaned of wind-blown debris and leaves.

The price advantage of resistive representatives is greatly overshadowed by the energy consumption that occurs due to uniform heating that is not always required. But the more expensive self-regulating cable allows you to save costs due to its ability to adapt to real weather conditions.

A self-regulating cable generates heat from a polymer matrix installed between a pair of current-carrying wires. The matrix polymer is enriched with inclusions capable of conducting current, the connections between which are disrupted when the temperature background increases. Broken bonds force the process of heat release to be interrupted; when the temperature drops, the bonds are restored again.

A self-regulating cable can simultaneously provide different heating intensities on the shady and illuminated sides of the roof. This allows you to significantly save on energy costs. In addition, it does not require maintenance equivalent to the resistive type and is not afraid of local overheating. When laying, the consumption is less, because you can cut off the necessary piece, and not have to worry about the excess.

Heating system design diagrams

The layout and length of the heating cable is determined by the configuration and steepness of the roof. How simpler design and the higher the slopes are inclined, the less footage will be required for heating.

Principles of laying heating cables

The installation of roof heating systems and drainage elements is confined to places prone to accumulating winter precipitation, these are:

• Endovy. Otherwise, grooves formed by adjacent slopes. They are equipped with a heating cable for a third of their own length, laid in the form of a long loop. The distance between the sides of the loop depends on the type of heating cable: for single-core resistive 10-12 cm, for double-core 40 cm, etc.
• Eaves of flat roofs. If the steepness of the structure is less than 30º, the heating system is installed at the bottom of the slope like a snake and covers the entire width of the eaves plus 30 cm above the conditional line of the house wall. With a slope of up to 12º, additional heating is built in areas adjacent to the drainage funnels.
• Gutter risers. The heating cable is located in the pipe cavity in the form of a long loop attached to the walls of the drain. If water is discharged into a storm sewer, the cable is inserted into it to the depth of seasonal freezing. If heating the sewer is not possible, it should be closed for the winter.
• Drainage funnels of flat roof structures. The cable around the funnels covers an area of ​​0.5 m on each side. The cable is looped inside the funnel to the level warm room inside the building.
• External wall drainage funnels. They require their own heating only if they are located on the wall separately from the gutter.
• Parapets. Usually one branch of the heating cable is laid along them.
• Adjunctions. They are arranged according to the parapet scheme.
• Flat roof water jets. The bottom of the water cannons and the adjacent area of ​​approximately 1 m² are equipped with a cable.
• Droppers. Depending on their design, they are heated in one or two branches.
• Gutters. The cable is laid in their cavity in two parallel rows. Drainage trays for internal drainage used in the construction of flat roofs are arranged in a similar way.

If 1 linear meter of a drainage tray or gutter receives waste from an area of ​​up to 5 m², then a cable power of 20 W/m is sufficient for heating. If the area being processed is larger, the power parameters need to be increased. For example, to treat 25 m² of roofing, a heating cable of 50 W/m or more will be required.

The installation of an anti-icing system does not always require cable heating of its eaves. From steep slopes, with an angle of inclination greater than 45º, snow is removed spontaneously. In such cases, the heating thread is pulled only in the elements of the drainage system. When ice forms around skylights, the cable is laid around them and in the direction of the drain.

In roof de-icing schemes that do not have a drainage system, the heating branch is laid out along the edge of the slopes or along a drip line. They require installation above the cable installation area and installation of a drip line on the eaves.

The heating cable is laid out along the roofing in several parallel branches or in a snake, maintaining a uniform step. The distance between adjacent branches depends on the power of the cable and the area of ​​the roof area being equipped. Note that using a cable with a higher declared power does not always lead to a reduction in its installation footage.

The cable is fixed to the roof using the methods indicated by the material manufacturers in the instructions. Only materials produced for these purposes are used for use in heating systems. The fasteners should not violate the tightness of the coating, the threads of the circuit should not sag freely in the air.

Specifics of power cable application

The anti-icing system is connected to three- or single-phase network via power cable. If connected to one phase of a 380V network, there is a probability of phase imbalance within 15%. To avoid distortion and to minimize it, it is recommended not to use systems consuming more than 6 kW. Anti-icing devices with higher power are connected to all three phases of a three-phase network. When connecting, the uniform distribution of loads across the phases is taken into account.

The cross-section of the supply cable determines the power of the planned load and the total length of the heating circuit. The power of the future load depends on the length and linear resistance of the branches. All actions for laying the power cable and connecting it to the heating threads are carried out in accordance with the PEU regulations.

The connection point between the heating and power cables should be located in the distribution box. Instead of a box, it is permissible to use a heat-shrink sleeve, which guarantees tightness at the joint.

Control and protection devices

The control equipment for anti-icing systems is designed to operate automatically or semi-automatically. Her responsibilities include starting the heating cables and turning them off within the operating temperature range.

There are two types of equipment for anti-icing systems:

• Thermostat. A device that responds to signals from temperature sensors. Switching on and off occurs when the temperature background goes beyond the operating limits (from +5º to -15º C).
• Weather station. A more complex device that responds to readings from humidity and temperature sensors. Allows you to adjust the operation of the heating system according to the fact of precipitation.

The first option is structurally simpler and, naturally, cheaper. However, in regions with high humidity it is capable of allowing for error and occasionally promoting the accumulation of ice instead of melting and the removal of precipitation. Weather stations are more sensitive to changes in background humidity, but like any complex system they fail more often.

More sensitive control carried out by the weather station makes it possible to save on energy consumption. In regions with moderate humidity, a thermostat is sufficient to equip anti-icing systems that are small in length and power.

In order to prevent destruction and melting of the insulation due to excess load current, the heating circuit is equipped with an automatic switch. Shutdown also occurs when current leaks through the insulating shell. The systems are protected from burnout due to a short circuit.

If there is a need for automatic control of individual sections of the heating circuit, it is supplemented with programmable switches, time relays, etc. It is undesirable to use a manual control scheme, because a person is not able to accurately respond to changes in the background and, for example, at night may miss the need to start or turn off.

Sensors for response systems to changing weather conditions are located in places accessible for maintenance. It is necessary to periodically clean them from dust and ice build-up if they form. The sensors are installed flush with the surface that is to be heated, and they are positioned so that they are visible to passing people.

Rules for operating anti-icing systems

Compliance with the instructions for the operation of heating circuits guarantees long-lasting and trouble-free operation of the system. It is recommended to trust the installation of the circuit to qualified workers who have undergone specialized training. For those wishing to make their own efforts in the construction, no one guarantees a successful result and replacement of damaged components.

The circuit installation must be completed before the first solid precipitation falls. It is advisable to choose late autumn for installation work. Delay may result in the formation of snow accumulations and blockage of drainage systems. In order to bring an icy system into working condition, it will be necessary to clean its components from ice.

Cleaning system elements should be done with extreme caution, because... any careless movement can lead to insulation failure. This is the most common reason for failure of the heating circuit as a whole. Components damaged by mechanical impact are not covered by the warranty.

Cable heating installers who have undergone system training during the work set the most suitable range, focused on local climatic factors. If you are installing an anti-icing circuit and determining the temperature limits yourself, then you should act in strict compliance with the manufacturer’s instructions.

Video about problems solved by installing cable heating elements roofing system:

Detailed instructions for installing an anti-icing system:

Demonstration of the specifics of using a self-regulating heating cable:

A visual demonstration of the construction of a roof and gutter heating system will help to understand the specifics of the process.

A properly executed anti-icing system for roofs and gutters will eliminate a lot of problems and extend the service life of materials. roofing pie and façade finishing.

When installing, all requirements and rules necessary for proper installation and long-term heating service must be observed. Information about technological principles and construction standards will help in carrying out work independently or in monitoring the work of hired installers.

Icicles or even a bank of ice can form on any roof during the winter season. Let's find out what means can be used to eliminate such phenomena.

We offer you a number technical solutions for roof heating, which will help combat icing of the roof and gutters. Ice and icicles can form on almost any roof. This is due to natural deficiencies design and is fraught with various consequences: from leaks to damage to the drainage system.

Roof and gutter heating solutions

• Selecting a heating cable
• Electrical equipment
• Roof heating installation

Purpose and principle of operation

Even with a well-designed roof, thermal protection is not absolute. As snow cover accumulates, heat leakage into the atmosphere decreases, the temperature of the roofing increases, which is why it gradually melts. Flowing down, the water reaches the bottom of the slope, where it finally freezes, forming an ice bank.

Above this shaft, new portions of water accumulate, the risk of leaks increases, and the snow cap continues to accumulate, increasing the load on the supporting system. At the first thaw, the entire accumulated mass of snow and ice comes off the roof like an avalanche, damaging the drainage system and posing a threat to people and property.

Heating the roof is an active anti-icing measure, the main task of which is to melt the resulting ice and facilitate the unhindered removal of melt water. Depending on the roof structure, the specific operation of the snow melting system may differ. Conventionally, roofs are classified according to the numerical value of heat losses:

1. Roofs over cold attics or unheated rooms That's what they call cold. The snow cap on them melts only on a sunny day near bare areas of the roof, and practically no ice forms. Heating of such roofs is required in cases where the amount of precipitation is high, and independent removal of the cover is impossible due to the small slope. In general, cold roofs are not heated.
2. Roofs over warm attics or attics with good insulation called moderately warm. This is the most difficult case: snow melts at a low intensity, which is why the thickness of the ice layer slowly but steadily grows. The purpose of the snow melting system is to speed up the melting of snow, while the system operates in a semi-automatic mode at infrequent but fairly long intervals.
3. Roofs with poor insulation are conventionally considered warm; snow melts on them very actively. As a rule, ice formation occurs in the lower part of slopes and gutters, so heating elements are placed only in these areas. Their power is quite high, the system operates in intermittent mode.

Selecting a heating cable

To heat roofs, two types of two-core heating cables are used. The first option is a heating section of fixed length and power, this is the most convenient way heating gutters and pipes.

There are also self-regulating cables, consisting of two parallel conductive cores, the space between which is filled with a weak dielectric, the resistance of which increases abruptly when heated to a certain temperature. Thanks to this, the self-regulating cable can be connected in segments of arbitrary length; only the maximum length of the line is limited.

Both types of cable have a rather complex structure. The heating core or pair is encased in a heat-resistant sheath with good dielectric properties. A shielding braid is wound over the shell - a protective measure in case of damage to the main electrical insulation. The cable is also covered in external insulation, which protects against both breakdown and mechanical damage.

The self-regulating cable also has an additional layer under the outer sheath that eliminates friction between the flat heating core and the outer insulation to maintain its shape.

All heating cables are divided by specific power, which can be 15–50 W/m.p. Cables up to 20 W/m.p. used on warm roofs, up to 30 W/m.p. - on cold areas of moderately warm roofs, up to 50 W/m.p. - for heating the drainage system.

Electrical equipment

Since the electric heating system is operated in rather harsh conditions, and safety measures are much stricter than for heating open areas, the system requires the use of a number of electrical products and protective devices.

The electrical connections require the most attention. In conditions high humidity and exposure to ultraviolet radiation, standard couplings for heating cables do not demonstrate sufficient reliability. Therefore, they are used only for connecting heating cables to each other or in conditions where installation of a secure connection is impossible.

In other situations, the connection of the heating cable to the power cable is carried out internally distribution box with degree of protection IP66 via screw terminals. The box is placed below the roof overhang, which slightly increases the consumption of the heating cable, but is guaranteed to protect the vulnerable spot.

The worst thing that can happen to a heating system is an insulation breakdown and a short circuit between the cores or metal coating roofs. Therefore, a circuit breaker for protecting a line is selected in strict accordance with its power and the current supply voltage.

You need to select the machine that is closest in rating, and then adjust the heat splitter according to the instructions. The second stage of protection is a fire class RCD, designed for leakage currents of 200–400 mA. For its correct operation, the shielding braids of all heating cables must be reliably grounded.

The self-regulating cable is used in systems with manual activation and does not require the installation of a thermostat. The exception is heating systems for roofs of houses that are not designed for permanent residence, or if the goal is to make the heating operation completely autonomous.

In such cases, the thermostat turns off the heating when the air temperature reaches positive, and the automation can also use the readings of the humidity sensor to determine the presence of precipitation. For heating sections, installation of a thermostat is mandatory; the cut-off temperature is selected in the range of +3...+10 °C depending on climatic conditions. The temperature sensor is not located on outdoors, and is rigidly fixed 20–25 mm from the heating element.

Roof heating installation

The arrangement of cables on cold and warm roofs is different. In the first case, the heating elements rise in parallel lines along the entire length of the slope in increments of 30–40 cm. This heating system is used only on flat roofs with a slope of less than 10°, where independent removal of the snow cap is impossible.

In all other cases, only the lower cold edge, where ice accumulates, is heated. For warm roofs, the width of the heating strip is equal to the protrusion of the covering beyond the outer plane of the wall.

On moderately warm roofs, heating is arranged to the width of the overhang and wall plus 10–15 cm. The cable is laid in a triangular snake with a distance between the peaks of 25 to 100 cm, depending on the density of the heating elements.

It is determined by the required specific power of the heated area, which for moderately warm roofs is 250–300 W/m2, and for warm ones - about 400 W/m2. Depending on climatic conditions, the manufacturer may give additional recommendations for power adjustment.

Fastening the cable to the roof with a snake pitch of more than 50 cm is carried out with point fasteners, which are attached to the covering with self-tapping screws or blind rivets. Before fastening, a special sealant is placed between the fastener and the roof. If the snake pitch is quite frequent, it is better to fasten it on a perforated mounting tape.

It is attached with two parallel lines at the bottom of the slope and with the required distance from the edge, after which the cable is pressed by bending the cut petals. This method is especially often used on steep slopes, where there is a high probability of the snow cap falling off: the cable will not be damaged, the fastenings will simply unbend.

Special attention should be given to wind overhangs and valleys. On each overhang, the cable should rise from the bottom to 2/3 of the height of the slope. An excessive amount of ice forms in valleys and gutters, so the specific heating power should be increased by 1.5 times. As a rule, this is achieved by laying two or three parallel lines of heating cable on both sides of the valley with a pitch of 10–12 cm.

Anti-icing of the drainage system

With an existing roof heating system, it is necessary to lay heating cables also in drainage trays and drainage pipes. Without this, the melted water will not be able to drain freely, will freeze and, most likely, damage the drainage system.

As a rule, two cables with a power density of more than 25 W/m.p. are sufficient for gutters. One of them is laid along the outer side, the other - along the bottom of the gutter. Fixation is carried out using special brackets, which are fixed inside the tray in increments of 20–30 cm. If during operation there is freezing of water in the drain, you can add another heating cable.

Pipes are the most vulnerable part of the drainage system; due to cable tangling, plugs can form inside them, and the entire system will become unusable. Therefore, cables with a power of up to 50 W/m.p. are usually chosen for pipes. with high operating temperature.

They are mounted in a tensioned state: the gutter heating cable is lowered to the very bottom, secured at the bottom with a double bend to prevent freezing of the outlet socket, and then pulled back up. Particular attention should be paid to the receiving funnels: heating elements in them are laid in one or two rings around the perimeter.published

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If you have any questions on this topic, ask them to the experts and readers of our project.

We offer you a number of technical solutions for roof heating that will help combat icing of the roof and gutters. Ice and icicles can form on almost any roof. This is due to natural design flaws and is fraught with various consequences: from leaks to damage to the drainage system.

Purpose and principle of operation

Even with a well-designed roof, thermal protection is not absolute. As snow cover accumulates, heat leakage into the atmosphere decreases, the temperature of the roofing increases, which is why it gradually melts. Flowing down, the water reaches the bottom of the slope, where it finally freezes, forming an ice bank. Above this shaft, new portions of water accumulate, the risk of leaks increases, and the snow cap continues to accumulate, increasing the load on the supporting system. At the first thaw, the entire accumulated mass of snow and ice comes off the roof like an avalanche, damaging the drainage system and posing a threat to people and property.

Heating the roof is an active anti-icing measure, the main task of which is to melt the resulting ice and facilitate the unhindered removal of melt water. Depending on the roof structure, the specific operation of the snow melting system may differ. Conventionally, roofs are classified according to the numerical value of heat losses:

1. Roofs above cold attics or unheated rooms are called cold. The snow cap on them melts only on a sunny day near bare areas of the roof, and practically no ice forms. Heating of such roofs is required in cases where the amount of precipitation is high, and independent removal of the cover is impossible due to the small slope. In general, cold roofs are not heated.
2. Roofs over warm attics or attics with good insulation are called moderately warm. This is the most difficult case: snow melts at a low intensity, which is why the thickness of the ice layer slowly but steadily grows. The purpose of the snow melting system is to speed up the melting of snow, while the system operates in a semi-automatic mode at infrequent but fairly long intervals.
3. Roofs with poor insulation are conventionally considered warm; snow melts on them very actively. As a rule, ice formation occurs in the lower part of slopes and gutters, so heating elements are placed only in these areas. Their power is quite high, the system operates in intermittent mode.

Selecting a heating cable

To heat roofs, two types of two-core heating cables are used. The first option is a heating section of a fixed length and power; this is the most convenient way to heat gutters and pipes. There are also self-regulating cables, consisting of two parallel conductive cores, the space between which is filled with a weak dielectric, the resistance of which increases abruptly when heated to a certain temperature. Thanks to this, the self-regulating cable can be connected in segments of arbitrary length; only the maximum length of the line is limited.

Both types of cable have a rather complex structure. The heating core or pair is encased in a heat-resistant sheath with good dielectric properties. A shielding braid is wound over the shell - a protective measure in case of damage to the main electrical insulation. The cable is also covered in external insulation, which protects against both breakdown and mechanical damage. The self-regulating cable also has an additional layer under the outer sheath that eliminates friction between the flat heating core and the outer insulation to maintain its shape.

All heating cables are divided by specific power, which can be 15-50 W/m.p. Cables up to 20 W/m.p. used on warm roofs, up to 30 W/m.p. — on cold areas of moderately warm roofs, up to 50 W/m.p. - for heating the drainage system.

Electrical equipment

Since the electric heating system is operated in rather harsh conditions, and safety measures are much stricter than for heating open areas, the system requires the use of a number of electrical products and protective devices.

The electrical connections require the most attention. In conditions of high humidity and exposure to ultraviolet radiation, standard heating cable couplings do not demonstrate sufficient reliability. Therefore, they are used only for connecting heating cables to each other or in conditions where installation of a secure connection is impossible. In other situations, the connection of the heating cable to the power cable is carried out inside a distribution box with a degree of protection of IP66 through screw terminals. The box is placed below the roof overhang, which slightly increases the consumption of the heating cable, but is guaranteed to protect the vulnerable spot.

The worst thing that can happen to a heating system is a breakdown of the insulation and a short circuit between the wires or to the metal roofing. Therefore, a circuit breaker for protecting a line is selected in strict accordance with its power and the current supply voltage. You need to select the machine that is closest in rating, and then adjust the heat splitter according to the instructions. The second stage of protection is a fire-class RCD, designed for leakage currents of 200-400 mA. For its correct operation, the shielding braids of all heating cables must be reliably grounded.

The self-regulating cable is used in systems with manual activation and does not require the installation of a thermostat. The exception is heating systems for the roofs of houses that are not designed for permanent residence, or if the goal is to make the heating operation completely autonomous. In such cases, the thermostat turns off the heating when the air temperature reaches positive, and the automation can also use the readings of the humidity sensor to determine the presence of precipitation. For heating sections, installation of a thermostat is mandatory; the cut-off temperature is selected in the range of +3...+10 °C depending on climatic conditions. In this case, the temperature sensor is not located in the open air, but is rigidly fixed 20-25 mm from the heating element.

Roof heating installation

The arrangement of cables on cold and warm roofs is different. In the first case, the heating elements rise in parallel lines along the entire length of the slope in increments of 30-40 cm. This heating system is used only on flat roofs with a slope of less than 10°, where independent removal of the snow cap is impossible.

In all other cases, only the lower cold edge, where ice accumulates, is heated. For warm roofs, the width of the heating strip is equal to the protrusion of the covering beyond the outer plane of the wall. On moderately warm roofs, heating is arranged to the width of the overhang and wall plus 10-15 cm. The cable is laid in a triangular snake with a distance between the peaks of 25 to 100 cm, depending on the density of the heating elements. It is determined by the required specific power of the heated area, which for moderately warm roofs is 250-300 W/m2, and for warm ones - about 400 W/m2. Depending on climatic conditions, the manufacturer may provide additional recommendations for adjusting power.

Fastening the cable to the roof with a snake pitch of more than 50 cm is carried out with point fasteners, which are attached to the covering with self-tapping screws or blind rivets. Before fastening, a special sealant is placed between the fastener and the roof. If the snake pitch is quite frequent, it is better to fasten it on a perforated mounting tape. It is attached with two parallel lines at the bottom of the slope and with the required distance from the edge, after which the cable is pressed by bending the cut petals. This method is especially often used on steep slopes, where there is a high probability of the snow cap falling off: the cable will not be damaged, the fastenings will simply unbend.

Particular attention should be paid to wind overhangs and valleys. On each overhang, the cable should rise from the bottom to 2/3 of the height of the slope. An excessive amount of ice forms in valleys and gutters, so the specific heating power should be increased by 1.5 times. As a rule, this is achieved by laying two or three parallel lines of heating cable on both sides of the valley with a pitch of 10-12 cm.

Anti-icing of the drainage system

With an existing roof heating system, it is necessary to lay heating cables also in drainage trays and drainage pipes. Without this, the melted water will not be able to drain freely, will freeze and, most likely, damage the drainage system.

As a rule, two cables with a power density of more than 25 W/m.p. are sufficient for gutters. One of them is laid along the outer side, the other along the bottom of the gutter. Fixation is carried out using special brackets, which are fixed inside the tray in increments of 20-30 cm. If during operation there is freezing of water in the drain, you can add another heating cable.

Pipes are the most vulnerable part of the drainage system; due to cable tangling, plugs can form inside them, and the entire system will become unusable. Therefore, cables with a power of up to 50 W/m.p. are usually chosen for pipes. with high operating temperature. They are mounted in a tensioned state: the gutter heating cable is lowered to the very bottom, secured at the bottom with a double bend to prevent freezing of the outlet socket, and then pulled back up. Particular attention should be paid to the receiving funnels: heating elements in them are laid in one or two rings around the perimeter.