How roof and gutter heating works. Heating of roofs and gutters: calculation, design and installation of anti-icing cable systems Electric wire for melting snow on the roof

Modern roofs have not only a beautiful, but also high-quality coating, which perfectly protects the house from street noise, air mass flows, and also from moisture penetration. However, the formation of ice due to snowfall can greatly harm any roofing building material. That is why you should take care of its special heating system.

  • roof collapse may occur due to too much snow load;
  • irreparable damage to engineering systems and roofing may be caused;
  • the descent of icicles and snow can injure people passing by;

  • melt water can accumulate in drainpipes and clog them when frozen.

The above phenomena today can be eliminated in several ways:

1. With the help of manual snow removal.
2. With the help of a special roof heating system.

As for the first option, professional climbers are most often involved in such work. If you try to clean the roof with your own hands, then due to inexperience or negligence, you can seriously harm yourself.

A more effective method in this case is cable heating of the roof, the system of which is very simple. It consists of:

  • certain control system;
  • information and distribution network;
  • heating part.

Such a system is launched with the help of an operator, after which it can function for a long time in automatic mode, focusing solely on the performance of sensors.

However, it should be noted that the use of this heating system by no means eliminates the need for laying high-quality waterproofing on the roof between the base and the outer coating.

Benefits of using a dedicated roof heating system

  • automatic system provides ease of control;
  • possible roof leaks are neutralized;
  • more gentle conditions are created for the operation of the roof;
  • the formation of additional loads on the roofing building material and load-bearing structures is excluded;
  • there is no need for manual cleaning of the roof;
  • is the most rational way to deal with frost.

Types of electrical cables for creating heating systems

All cables used for roof heating systems differ in:

  • the possibility of changing the set length;
  • recommended areas of use;
  • specifications.

Roof heating cable classification:

1. Armored cable.

This type of heating cable is very similar to resistive. The difference lies in the increased mechanical strength and higher heating temperature. It is these characteristics
allow it to be installed on a roof that belongs to the category of exploited ones, as well as to be laid directly on concrete. At the same time, the design of the heating armored cable provides a slight adjustment of its length, namely, cutting from 1-2 m.

2. Resistive cable.

This material is characterized by a very low cost, a certain length of the section and a power of 5-30 W / m. Thanks to such simple indicators, it is more often used to create do-it-yourself roof heating.

Flaws:

  • has equal heat transfer along the entire length, which is sometimes not enough to deal with certain areas of ice;
  • fixed length makes installation difficult;
  • due to the fact that the power of the cable in some places is not enough, there is an excessive consumption of electricity.

3. Zone cable.

This type of cable is mainly used for downpipes and gutters. Like resistive, it has a certain power, but unlike it, it can be adjusted to the desired size directly on the construction site. The most rational is its use in systems that operate in conditions requiring a complete absence of ice.

4. Self-regulating cable.

The price of such a heating cable is much higher than the previous types, but its choice will be worth the money you spent.

Advantages;

  • has the ability to perfectly adapt to environmental conditions;
  • it can be trimmed at the site of the work being carried out;
  • can be mounted in segments of arbitrary length;
  • Thanks to its use, significant energy savings occur.

Its most common modifications are those based on polyolefin and fluoroplast. The latter are distinguished by good power, increased resistance to many aggressive environments, and the former are used to heat the roof solely on the basis of the manufacturer's recommendations.

Roof anti-icing system

In addition to the heating cable, the following elements must be included in such systems:

  • roof funnel with electric heating;
  • snow retention elements that protect the cable from damage;
  • directly heating part, which comes complete with clamps;
  • control cabinet;
  • distribution network;
  • various sensors that control temperature;
  • information cables;
  • power cables;
  • protective shutdown equipment that de-energizes the lines in case of violation of the quality of the insulation;
  • temperature controllers, which are specially adapted for the installation of a heating cable on pitched roofs.

How to make a warm roof

Heating cable installation

To fix the heating cable, various types of fastening sets are usually used, which consist of cables, puffs, clips and perforated metal tapes.

Specially mounted sections of cables for the roof heating system and wires from control sensors are reduced to a mounting box, which is usually located in the attic. Then the power cable from the junction box is led to the heating system control cabinet.

As for large facilities, the control and management of the heating process is carried out automatically using a complex thermostat equipped with temperature and moisture control sensors. At the same time, all roof elements in the areas where heating cables are located remain free of ice. At small objects, it is possible to turn on the system manually using a timer on duty or a conventional thermostat.

The principle of operation of the heating cable

Since the heating cable is connected and fixed to the power equipment, it should be provided with switches and thermostats. The main goal of the regulatory system is to free the way for the flow of melt water and accompany it to the lower cut of the drainpipes.

The snowmelt assist system must function as long as there is a risk of icicles.

The process of melting snow on the roof occurs depending on:

  • wind forces;
  • air humidity;
  • ambient temperature;
  • the amount of heat generated;
  • roof structures, etc.

Sometimes situations arise when snow melts on the roof, but icicles and ice do not occur. In this case, it becomes necessary to operate the control system, which, with the help of special temperature and humidity sensors, begins to monitor the entire situation and turns on the heating at certain intervals, without wasting electrical energy.

If the heating cable is mounted on a roof with a soft coating, then its maximum power is often limited to 20 W / m. For high-quality fixation of the material during the installation process, a mounting tape with a fastening step of 3 cm should be used. It is also possible to fix the lines on the grid using clamps.

Self-regulating heating cable video:

Such a phenomenon as roof icing is very dangerous both for people near the roof and for the structure of the roof itself. Roof heating is the optimal solution for keeping it in perfect condition during the cold season. This system will prevent the accumulation of ice and snow, which will simply melt, and the resulting water will continue to flow down the water collectors.

Does your home need a roof heating system?

In the temperate zone, the weather during the cold period is very severe, with a predominance of negative temperatures, alternating with heavy snowfalls and thaws. The main task of the homeowner in such difficult weather conditions is to confront the freezing of the roofing and water runoff on his house. Ice freezes in the drainage elements, and the water that melted during the thaw looks for workarounds. As a result of this process, leaks appear, gradually destroying the walls and facades of housing construction, damaging the roofing system of water flow - plastic is especially affected.

Large blocks of ice falling off buildings can hit people or vehicles, or damage other property. The results of such a phenomenon can be very dangerous.

The existing practice of struggle allows you to eliminate the ice problem manually, with the help of an improvised tool - scrapers or shovels. Unfortunately, such removal of snow and ice from roofs often results in damage to the roofing or other elements located on the roof, as well as unplanned financial expenses for the elimination of damage. It is easier and more cost-effective to install an anti-icing system on the roof surface, which provides heating of the roof from snow and ice.

Such an auxiliary system helps to increase the time of use of the roof and ensure the safety of all elements of the drainage system in working order, as well as protect the building facade from damage. Heating will prevent the formation of ice or icicles on the roofing, which often unsafely fall down during thaws. Components of the heating system are placed on an already fully built roof, and then they are operated autonomously.

Heating of roof surfaces is switched on at the moments when weather conditions for icing of the roof are formed, and is automatically switched off after cleaning the roof structure and draining water from ice.

These systems use cables specially designed for this purpose - safe and reliable, withstanding sudden changes in temperature, resistant to changes in the intensity of precipitation and the amount of incident sunlight.

It is important to provide for the installation of a roof heating system when drawing up a roof construction project.

Roof heating: principles of operation of heating systems on the roof

Anti-icing systems for installation on roofs and gutters have only recently become popular and have quickly become very popular. Thanks to the heating of the lower part of the roof, ice and icicles no longer appear there, and the heating of the drainage system reduces the amount of ice that destroys the gutters and drainage pipes.

One of the main tasks of the roof heating system is to ensure the unhindered flow of water through the drain channels. The operation of such a system does not depend on the amount of snowfall, and almost does not depend on air temperature. It works in the air temperature range + 3 - -15 degrees. In temperate latitudes, at temperatures lower than in the above range, snow falls quite rarely, and therefore there are practically no conditions for ice formation. But there are components on the market for an increased power anti-icing system that also work during severe frosts.

When designing the installation of a roof heating system, in addition to design features, it is necessary to take into account factors that affect its effectiveness:

  1. prevailing wind direction and strength;
  2. location relative to the cardinal points of pitched surfaces;
  3. the level of solar heating of some roof surfaces.

Roof heating - the main components of the heating system:

  • heating cable and its mounting fixtures;
  • power and power distribution wires, including control and power cables, as well as distribution nodes;
  • a block that controls the entire system, including sensors for monitoring and measuring moisture and temperature.

The main component of the entire anti-icing system is the heating cable, which ensures the efficient operation of the entire system.

There are 3 types of cable for roof heating: self-regulating, resistor, zonal.

Also, these cables are shielded and non-shielded.

Another element of this system is the control unit, which automatically turns the system on and off when certain adjustable parameters are reached.

It is important to properly design a roof heating system and select the components necessary for its installation.

Economical roofing with efficient heating

Based on the parameters of the thermal regime, conventionally the roofs of houses are divided into 2 types:

  1. Cold roof - with high-quality insulation and low values ​​​​of heat loss through its surface, with proper ventilation of the space under the roof. Roof heating of this type is carried out by systems with minimal power, so heating cables are placed only in the drain.
  2. Standard warm roof or poorly insulated roof, with insufficient insulation to fully insulate the roof. The snow melts on it even at low temperatures outside. Moisture itself flows to the cold roof edge and to the drainage system. As a result, moisture freezes, forming ice and icicles. On such roofs, it is necessary to use an integrated anti-icing system, with the installation of heating elements on the roofing and in the drainage system. The power of the heaters used is much higher than that of a cold type roof.

The choice of a heating element begins with a consideration of the structural features of the roof. Modern roof heating cables do not ignite, they do not have breakdowns and electricity leakage. Such systems are used for roof heating at gas stations and kindergartens. Modern cable heating systems are safe and reliable to use.

Proper heating arrangements should be made in the water drainage systems to prevent ice build-up. Therefore, the bottom of the downpipes is additionally heated by placing elements of the drainage system inside buildings, in heated rooms. If the drain of the drainage system is connected to the sewer system, then the drains are heated to the level of freezing. It is necessary to protect the heating cable from damage, for example, from ice sliding along the roof during a thaw.

On the roof, it is necessary to cover the heating cable with sheet steel: in this case, it will not be visible, and, accordingly, will not violate the design of the house, and the cable itself will be additionally protected.

It is important to choose the right components for the roof heating system so that the system works as long and efficiently as possible.

The cable heating system for roofs and gutters is an anti-icing system based on the use of electric heating cables to melt snow and ice on the roof and in the drainage system of the building during periods of danger - at a time when daily temperature fluctuations occur and ice formation is most likely.

In turn, it is ice that causes roof leaks in the autumn-spring period, as well as the cause of deformation of gutters and gutters due to ice and snow accumulated in them.

Since the roof anti-icing cable system does not allow the formation and, accordingly, the fall of icicles on the adjacent territory, it is classified as a security system.

It is quite natural that in 2004 a document of the Moscow Committee for Architecture “Recommendations for the use of anti-icing devices on roofs with external and internal drains for residential and public buildings under construction and reconstruction” appeared, which directly recommends the installation of such systems on all new buildings.

Currently, several thousand buildings are equipped with cable roof heating systems in Moscow and St. Petersburg. Significant experience in design, installation and operation has been accumulated.

A properly designed and properly installed roof heating cable system based on high-quality components does not allow ice accumulation and ensures the removal of melt water along the entire route. As a result, the roof itself lasts longer, the gutters do not sag, the gutters do not deform, and people and cars in the vicinity of the building are not threatened by falling icicles.

Roof heating in photos

  • Warm and cold roof heating
    • In the case of a cold roof (having minimal heat loss), it is enough to revise the drainage system and install heating cables in gutters and gutters.
    • In the case of a warm roof, it is very likely that installation will also be required in other areas: valleys, drips (cornices), dormers, junctions and overhangs.
    • If the roof is completely iced over, then the installation of KSO may not be economically justified and the reconstruction of the roof suggests itself.

    System Composition

    The following classification seems to us the most successful:

    1. Subsystem of heating elements

    Heating cables for use on the roof are subject to increased requirements:

    • linear power: not less than 20 W/m and not more than 60 W/m at 0°С;
    • shell resistance to UV radiation;
    • resistance to local overheating;
    • reliable operation in wet conditions;
    • the presence of a shielding braid;
    • certification of compliance with TR TS 004/2011 "On the safety of low-voltage equipment";
    • certificate of conformity TR TS 012/2011 "On the safety of equipment for operation in explosive environments" * (if the building is located in an explosive zone, for example, a gas station).

    Roof and gutter heating systems use resistive cables and self-regulating cables.

    The advantages of resistive cables include low cost and stability of power characteristics. The disadvantages are the impossibility of changing the lengths of the sections and the likelihood of overheating. On soft (welded) roofing, resistive cables cannot be used.

    Resistive cables for roofing

In winter, housing and communal services and homeowners have to deal with snow and ice removal from roofs. This is a serious problem. Under the weight of a thick layer of snow, damage and even collapse of the roof is possible. Ice buildups pose a safety hazard to people. Icicles falling from the roof can damage cars parked near the building. Many people clean roofs the old fashioned way, by hand, but this is hard, traumatic and inefficient work. Recently, roof heating systems have been increasingly used, which are able to melt snow and ice and divert melt water away from the foundation of the house. Such devices greatly facilitate the care of the roof due to the automatic mode of operation.

  • Poor roof insulation.

A warm roof, a mansard roof, is more prone to the formation of an ice crust. A heated room under the roof contributes to the heating of the roofing. On such a roof, due to heat loss, snow melts even in frost. Melt water flows down the roof slope, freezes again on the cold cornice and in the drain, turning into icicles. In this case, first of all, the root cause is eliminated - the roof is insulated. With high-quality thermal insulation of the roof, the heating system will work more economically.

  • Seasonal and daily temperature fluctuations.

Even with proper design and construction of the roof, ice appears due to the temperature difference between day and night, especially in spring. During the day in the sun, the snow melts and flows from the roof into the drain, and at night, when the air temperature drops, it freezes, forming huge ice. Under the weight of ice growths, the drainage system becomes unusable.

The principle of operation of the system "without icicles"

The action of modern roof protection systems from frost is based on heating due to the heat transfer of an electric cable. The heating cable is laid on the roof, along gutters, downpipes, places where snow and ice accumulate. The cable heating system causes the snow to melt and allows the free flow of melt water from the roof to the ground some distance from the house.

What tasks and functions does the roof and gutter heating system perform?

  • Prevention of the formation of icicles, accumulation and fall of snow masses and ice layers.
  • Organization of normal regular removal of melt water from the roof and gutters.
  • Exclusion of blockage and deformation of the drainage system with ice plugs.
  • Reducing the mechanical load on roof structures.
  • Elimination of the problem of manual cleaning of the roof from snow and ice.
  • Extending the life of the roof.
  • Full automation of roof heating and no need for human participation in system management.

Composition of the roof and gutter heating system

  • Heating cable
  • Fasteners
  • Switchboard:
    • input three-phase circuit breaker;
    • four-pole contactor;
    • protective shutdown device, (30mA);
    • single-pole circuit breakers for each phase;
    • signal lamp;
    • circuit breaker for thermostat control;
  • Distribution network components:
    • power supply cable;
    • signal cable between thermostat sensors and control unit;
    • mounting boxes;
    • connecting and terminating couplings for a heating cable.

Roof heating system

  • The heating part is an electric cable that provides heating directly to the roof and gutters. It is carried out from the outside of valleys, gutters, weirs, storm drains, trays, downpipes. The heating electric cable for roof heating must comply with fire safety requirements, have high mechanical strength, resistance to temperature fluctuations, exposure to sunlight, and precipitation. The heating cable system for deicing is quite easy to install, designed for all types of roofing, not dismantled for the summer season, has automatic control.
  • Distribution and information part consists of information and power cables, mounting elements, junction boxes. It performs the function of distribution and transmission of electrical power for the heating part and the exchange of signals between the roof heating control sensors and the control cabinet.
  • The control system includes: temperature controllers, air temperature sensors, a control cabinet (board), starting and protective devices, control devices. Selection and completion of the control system is carried out in accordance with the capacity of the roof anti-icing system. Self-regulating electric cables in heating systems of drains are able to work without automatic control. They independently regulate their power under the influence of precipitation and air temperature. However, for efficient and economical operation of the heating system, it is recommended to use thermostats.

Roof heating installation. Instruction

Installation of heating of roofing cornices and gutters is carried out in the following order:

  • The heating sections are checked for compliance with the dimensions of the roof heating zones, sections of the required length are cut, couplings are installed, laid out and fastened.
  • The electrical cable in the gutters is fixed with strips of mounting tape across the gutter. The thicker the mounting tape, the stronger and more durable. For a resistive cable, the tape installation step is 0.25 m, for a self-regulating cable - 0.5 m. When fixing the tape on the gutter with rivets, a sealant is additionally used.
  • In downpipes, the electrical cable is fixed with a mounting tape or a heat-shrinkable tube. When the pipe height is more than 6 m, the cable is additionally attached to a metal cable with an insulating sheath to reduce the bearing load.
  • In the mark of the pipe and the funnel, the heating electric cable is fixed with mounting tape with rivets.
  • The electrical cable is fastened to the roof surface using mounting tape and sealant.
  • They put mounting boxes, call and measure the insulation resistance of the heating sections.
  • Mount thermostat sensors, conduct signal and power cables.
  • Install the control cabinet.
  • Measure resistance and ring power and signal cables.
  • Check the safety device.
  • Adjust the thermostat.
  • Carry out commissioning work.

Do-it-yourself installation of roof heating and gutters

Installing a heating system for the roof is quite a costly and complicated matter, but fully justified. You can assemble such a system with your own hands, but it is better to entrust the calculation and verification of equipment before starting it to professionals in order to guarantee the safety of electric heating.

The procedure for designing a heating system for roofs and gutters

  • Definition of roof heating zones.
  • Choice of electric cable in accordance with installation conditions.
  • Choice of control system.
  • Locate junction boxes.
  • Planning the quantity and method of laying the heating cable.
  • Calculation of the power of the system, calculation by phases, selection of the system of circuit breakers.
  • Choice of mounting method for power cables.
  • Selection of automatic equipment for the control cabinet (board).
  • Preparation of a complete set of project documentation.

How to define heating zones

As heating zones, places of accumulation of snow and ice on the roof are selected. The formation of ice is influenced by weather conditions, the material and construction of the roof. The scheme of simultaneous heating of valleys, roof overhang and drain is considered optimal. In order to save money, many lay the cable only on the surface of the roof, mistakenly believing that this is enough. In fact, very often ice jams form in gutters and downpipes, blocking the path of melt water.

The quality of the organization of drainage depends on the correct choice of the place for laying the heating cable. First of all, the heating cable is laid in areas where ice is most likely to form: gutters, drainpipes, valleys. The total length of the electric cable for the anti-icing system is equal to the total length of the composite roofing elements that require heating.

On roofs with steep slopes, where there is a danger of avalanche-like ice and snow, a snow retention system is installed and a heating cable is laid in a zigzag pattern between the roof edge and the snow retainer.

In the absence of such a need, they are limited only to electric heating of gutters and pipes.

Choosing a heating cable

The basis of the heating system of the roof and gutters is a resistive and self-regulating electric cable with a power of 20 to 50 W per meter.

  • A resistive cable is an ordinary wire made of a metal core and insulation. It has constant resistance, stable heating temperature and constant power. Resistive cable has a low cost. The principle of operation of the cable is that the metal core is heated due to internal resistance. Heating gutters in this way is quite simple, the operation of the system is not complicated and expensive. It is mainly used for heating extended sections of roofs and gutters. The best option is to run a zonal resistive electrical cable with a special nichrome heating thread. The linear power of such a cable does not depend on the length, it can even be cut if necessary.
  • Self-regulating cable is more technologically advanced. It consists of a matrix, an insulating sheath, a braid and an outer sheath. The matrix, a heating self-regulating element, changes the resistance and degree of heating depending on the ambient temperature. As the air temperature in the cable matrix increases, the number of conductive paths decreases, resulting in a reduction in power, electricity consumption and temperature of the self-regulating cable. The power of the self-regulating cable is selected depending on the diameter of the drain.
  • Mixed type of cable. A reasonable compromise in terms of price and quality is considered a combined cable system. Typically, inexpensive resistive type cables are used for the roofing part of the system, and self-regulating cables are more suitable for heating gutters and pipes.

Comparative characteristics of resistive and self-regulating cables

Both types of heating cables are able to provide equally effective heating of the roof and gutters. However, each of them has its own advantages.

Resistive heating cable features:

  • Low cost.
  • Small starting current.
  • Constant power input and good heat transfer. Although in some cases, this can become a significant disadvantage, since due to different heat needs, some sections of the roof may overheat, while others may not receive sufficient heating.
  • Ease of system installation. The resistive cable is carried along the gutters and pipes or wrapped around them.

The disadvantages include: increased power consumption, design limitations, shorter service life compared to a self-regulating cable, and the likelihood of local overheating at overlap points.

Despite the high cost, for heating the roof, experts still prefer to use a self-regulating cable, which is produced using a special technology. Due to the unique molecular structure, the self-regulating cable is sensitive to atmospheric conditions and independently regulates heat transfer in each section depending on the temperature regime.

These properties of the cable allow the system to operate more efficiently and economically.

Advantages of self-regulating heating cable:

  • Cable laying in one line. In this case, there is no need to install jumpers, the likelihood of clogging the drainage system is reduced, the heating wire does not interfere with the timely outflow of water.
  • Easy installation. The cable is cut into parts of any length directly on the site during installation work. This possibility, as well as laying the cable in one thread, speeds up the pace of installation and reduces its cost.
  • Saving energy consumption. In the case of using a self-regulating heating cable, energy savings are more than 50%.
  • No risk of overheating and cable burnout. The wires of the resistive cable are prone to entanglement during the snow mass from the roof of the building, which leads to their local overheating. In the case of a self-regulating wire, this problem does not exist, since tangling is unlikely when laid in one thread, in addition, in places of overlap or contact, the heat transfer of the heating cable is automatically reduced.
  • Reliability. Without mechanical damage, the self-regulating electrical cable ensures 100% reliability of the system.
  • Durability of operation. The service life is 30 years, which is several times longer than that of a resistive cable.

Choice of control system

The control system can significantly reduce energy consumption depending on weather conditions. The heating system is controlled by two types of devices:

  1. The actual thermostat, which turns on the heating system in a given temperature range, usually within -8 +3 degrees.
  2. Weather station. In addition to the temperature regime, the weather station monitors the presence of precipitation on the roof and their melting. The station includes a temperature sensor, a humidity sensor. Some weather stations are equipped with both a rain sensor and a melt sensor.

When using a conventional thermostat, the user has to independently turn on the system in the presence of precipitation and turn it off in their absence. The weather station fully automates the operation of the system and even programs time-out delays.

Location of junction boxes

Junction boxes must be accessible for maintenance. Usually they are mounted on the roof near the heating sections. Installation on parapets, an attic, protections, under peaks is also possible.

Heating cable layout

Before starting the installation of heating of gutter systems and roofs, it is necessary to carefully calculate the length of the cable and determine its location. The length of the valley, all parts of the system is measured, the number and linear footage of the drain pipes are taken into account. For a 100-150mm gutter, a power of 30-60W per linear meter is required; for a 150mm wide gutter, the calculated power is 200W per square meter.

Cable electric heating is laid in the following parts of the roof:

  • Gutters, gutter elements, areas around them. Calculation of the length of the heating wire is carried out according to the drawing, taking into account the length of the gutters and a 10% margin. The number of threads of the electric cable depends on the width of the gutter based on a specific power of 400 W/m. Fastening is carried out using mounting tape and rivets.
  • Cornices.
  • Gutters and pipes. A self-regulating electrical heating cable should be used for downpipes. In the case of installing a resistive cable, to prevent contact between the threads, separators are placed at intervals of 25-30 cm from each other. The number of threads depends on the diameter of the downpipe, material and climatic conditions.
  • Drainage trays, water collectors.
  • Valleys and joints of individual parts of the roof. The number of cable threads varies from two to four. The cable is fixed in the valleys from below and from above using a mounting tape and a cable.

System power calculation

When choosing the power of heating cables, they are guided by standard indicators. The norm for resistive type cables is power 18-22W per linear meter, for self-regulating cables - 15-30W per meter. It should be remembered that if the gutter system is made of polymer, the cable power should not exceed 17W per linear meter, in order to avoid damage to the gutter due to the high heating temperature.

Power Cable Routing

Tracing is carried out in accordance with the requirements of the PUE, depending on the conditions of the room in which the cables are laid.

Selection of automatic control cabinet equipment

It is obligatory to install an RCD leakage block I ut = 30 mA for reliable protection against electric shock in extreme situations.

Installation of roof heating and gutters video

During installation, the wiring of the electrical cable is carried out in the most inconspicuous and accurate way. For installation of heating wires on the roof, reliable mounting clips made of copper, brass, galvanized steel are used, which do not require holes. They have a variety of shapes and firmly fix the cable, are resistant to temperature factors and are aesthetically pleasing.

To heat the roof and downpipes, heating electric cables with a power of up to 25 W / m are used. For soft roofing, plastic downpipes and gutters, a cable with a maximum heating power of not more than 20W per linear meter is used.

To obtain the required power on the heating area, the heating wires are laid with a certain fastening step. Mounting tape is used for fastening. Most often, the cable is fixed in increments of 3 cm. Each situation requires an individual approach, therefore, before installing the heating system, it is recommended to calculate the power in relation to a specific roof and drain.

For fixing the heating cable, a mesh with clamps is also used. Tighten the clamps carefully, otherwise damage, pinching and the occurrence of overheating zones of the cable will disable the entire heating system.

Laying electrical cables in gutters and downpipes.

A gutter is a horizontal part of a drainage system. It can be a separate roof element, a hanging channel, or part of the entire gutter and roof structure. In the gutter, the electrical cable is laid in one or more parallel lines. If the roof is "cold", for a gutter with a standard diameter of 100-120 mm, two lines of heating cable with a linear power of up to 50 W / m are sufficient. With a gutter diameter greater than the standard value, the number of lines is increased to 4-5. If the roof belongs to the category of "warm", then the number of lines is calculated according to the heating power of 100 W / m. Fix the heating wire in the gutter with special plastic fasteners or stainless mounting tape.

Downspouts are the vertical part of a drainage system. The distribution of heat at the top and bottom of the pipe is different. Due to the height difference, strong convection currents arise, causing the redistribution of heat along the entire length of the downpipe. As a result, the vertical drain in the lower part is cooled by the influx of cold air, and the top of the pipe is heated by the sun's rays. In order to compensate for heat loss and equalize thermal conductivity, the lower part of the pipe is additionally insulated by increasing the number of turns of the heating wire.

To further enhance the heating of funnels and outlet sections of drainpipes, two cable lines with a power of 20-30W per linear meter are laid, depending on the diameter of the pipes.

To prevent the appearance of ice on the roofing cornice, a “snake” cable laying scheme is used. Such a scheme involves wiring an electrical cable along the edge of the eaves. The zigzag step on hard roofs is carried out in multiples of the pattern, and on soft roofs, taking into account the power consumption per square meter (35-40 cm). The height of the "snake" is chosen so as to prevent cold zones on the heated surface and the formation of an ice crust.

The method of fixing the heating cable on a vertical drain is similar to fixing the wire in the gutters. Mounting tape or plastic fasteners are also used for installation. When laying the cable in the pipe, it is important to ensure that the cable lines do not intersect and do not come into contact with each other. If the length of the drainpipe is more than 2m, then the cable is attached to a special cable with a plastic sheath.

The valley is the inner corner of the roof surface, where snow and ice most often accumulate and remain for a long time during the thaw period. The greater the snow-ice mass, the greater the possibility of corrosion of the roofing material and the descent of the block down. In the valleys of the roof, the electrical cable is laid up and down. The length of the heating cable laying occupies 2/3 of the entire length of the valley, and the distance from the beginning of the overhang is at least 1 m. The design power indicators are 250-300W per square meter of the valley.

Installation of roof heating without holes

Roof heating systems and installation methods are constantly being improved. Heating cable fasteners that require holes are gradually being replaced by newer, more forgiving devices. For fastening heating cables in particularly difficult conditions, a special aluminum tape has been developed, designed for decades of operation. The cable is fixed with tape along the entire length and pressed tightly against the roof. Due to the good thermal conductivity of aluminum, a track 10–14 cm wide warms up along the cable, much more than with conventional fasteners. Installation does not require any holes. Such fasteners withstand snow falling from the roof and reliably protect the cable from kinks along its entire length.

Installation with the use of aluminum tape is carried out at a positive temperature. Therefore, such a system is installed before the onset of cold weather.

Installation quality check

After installation work, the roof heating system is monitored, namely:

  • Measurements of insulation resistance of heating sections, power cable. The measurement results are recorded in the protocol.
  • Checking current-carrying cables with a tester.
  • Trial run of the system.
  • Checking the temperature controller, adjusting the system.
  • The final adjustment of the temperature controller is carried out in the cold season.

Upon completion of commissioning and testing of the heating system of the roof and gutters, as-built documentation is drawn up:

  • Certificates of all system components.
  • System passport.
  • Passport of the control cabinet.
  • Passport of the temperature controller.
  • Insulation resistance measurement protocols.

Features of installation of heating of various types of roofs

There are many types of roofing materials and structures, drainage systems. Old houses are generally distinguished by bizarre roof shapes. Therefore, there are no standard solutions and ready-made schemes for all roofs. It is often necessary to design a heating system and choose the method of installation right on site, depending on the situation.

Warm roof

A warm roof is characterized by insufficient thermal insulation. In this case, the heating sections are additionally laid with loops along the very edge of the roof. The width of the loops is 30-50cm, the specific power of the system is 200-250W per square meter.

cold roof

A cold roof is well insulated, and there is often a well-ventilated attic. For such a roof, only heating of drains is installed with a linear power of 20-30W per meter, while the power is gradually increased to 60-70W in proportion to the length of the drain. All cables must be equipped with a protective disconnect device.

If the drain on the roof is not well organized, then in order to avoid the appearance of icicles, the roof slope needs additional heating. For this purpose, the heating cable is laid in the form of loops 0.5 m wide. Snow guards are used to protect the cable from mechanical damage.

If the roof is without gutters

Sometimes there is no drainage system on the roof of the building. In such situations, on a roof with a small slope, a “dripping edge” scheme is mounted, with a large slope - a “dripping loop”.

flat roof

The heating cable is laid along the entire perimeter of the roof in the lower part of the water drain line (deviation), it is led into an internal drain funnel at least 40 cm. (with an internal drain, i.e. inside the building), and on external trays - according to the “drip loop” scheme. In the areas where the roof adjoins the parapet, the power of the cable around the receiving tray is 40-80W per square meter. The cable is brought out into the tray itself and placed in the drain pipe.

tiled roof

A perforated fastening tape is used to fix the cable. On a new roof, the tape is nailed to the wooden base. If the tile is already installed, then the tape is brought 75 mm under the tile layer and attached to the adhesive.

Issue price

The cost of a roof heating system, gutters and its installation depends on various factors: the design, material and area of ​​the roof, the length of the drainage system, the type of heating cable, its power, the type of control system and other equipment, the manufacturer. The price of a self-regulating cable is from 240 to 660 rubles, the cost of a resistive cable is in the range of 90-150 rubles. Ready-made kits for heating roofs, gutters and pipes, consisting of a self-regulating heating cable with a power of 30 W / m and a supply wire, cost from 2290 to 13460 rubles.

The final amount can be called after the design and estimate work is completed. Many companies specializing in the installation of roof heating systems post prices on their websites and calculate the estimated cost of equipment and installation for free.

It is important to take into account not only the costs associated with the installation of an anti-icing system, but the subsequent operating costs. So, for example, the price of a resistive cable is 3-5 times less than a self-regulating one, but the power consumption is higher. Experts will help to give useful advice: what you can save on, and what you should not. You can always find a suitable option and develop the optimal installation scheme for roof heating.

A clean roof means a happy owner!

Modern equipment for roof heating greatly simplifies roof care, completely eliminates the appearance of ice on the roof and in gutters. High-precision sensors and temperature controllers work in standby mode, act immediately when needed and ensure minimal power consumption.

All the costs associated with the purchase and installation of equipment are not comparable to expensive roof repairs. Especially when it comes to the safety of people's lives, questions about the cost are not discussed.

A roof anti-icing system will once and for all save homeowners from removing snow from the roof with a shovel, knocking down icicles and ice blocks and annual roof repairs. A clean, strong and reliable roof will serve its owners as a reliable shield from any bad weather for more than a decade.

In winter, snow and ice are abundantly covered with roof slopes and gutters. Over time, they can slide down. Blocks of snow, icicles can fall on various objects that stand near the building, on cars, as well as on people passing by. This can be fraught with serious consequences. To avoid damage to property and injuries, electric roof heating is equipped.

This system is a wire that connects to a regular household network. For the arrangement of such heating, a cable of different types is used. How to choose and install an anti-icing system for gutters and roofs will be discussed next.

general characteristics

Prevents a lot of accidents, damage to various property in the winter. It not only contributes to the melting of snow and ice, but also prevents their formation on the surface of the roof and gutters. The presented device belongs to the security system. It is used today in various municipal and private facilities.

The principle of operation of the system is based on heating surfaces using electric current. In this case, it is important to correctly calculate the rated power of the wire, as well as mount it in accordance with the manufacturer's instructions. In this case, the system will be reliable and efficient.

On the market for heating products, there are many varieties of wires for such installation, which are produced by foreign and domestic companies. Roof heating cable price foreign production is about 7-10 thousand rubles. for 10 m. Domestic manufacturers present wires of similar quality and operating principle at a price of 5 to 8 thousand rubles. for 10 m.

System requirements

Produced in accordance with existing building requirements, rules for the installation of electrical equipment and instructions from the wire manufacturer. At the same time, increased requirements are put forward for the presented systems.

A cable that is suitable for heating the roof should have a power of 20-60 W / m. When choosing this indicator, they are guided by the features of the object, the climatic conditions in the region.

The wire must have a high insulation class. It should not collapse under the influence of ultraviolet radiation, overheat in certain areas. Reliable operation of the cable must be maintained in conditions of high humidity, temperature changes.

High-quality wire has a braid consisting of several different materials. There must also be a wire for grounding.

Varieties of systems

There are several options for roof heating. Such systems can be mounted using two categories of cable. The first is called resistive wire. Its heating will be the same along its entire length. This wire is similar to the cable used for underfloor heating indoors. It differs only in a higher rated power and a feature of the braid. The cost of a resistive wire on average leaves from 5 to 8 thousand rubles. for 10 m.

There is another type of electric cable, which is used to heat the roof and gutters. It is called self-regulating wire. The heating temperature of such a system may not be the same in different areas. This is a more advanced option. Its price will be higher. The average cost is, depending on the manufacturer, 8-10 thousand rubles. for 10 m.

In some cases, combined systems are used. A self-regulating type of wire is mounted in the gutters, and on the roof slopes - resistive cable.

Resistive Wire Features

It is a fairly powerful system. His vein is most often created from nichrome. This alloy rapidly heats up when electricity passes through it. The rated power of such a wire is 300-350 W/m. If this indicator is less, the system will not be able to perform the functions assigned to it in severe frosts.

There are several layers of insulating materials around the nichrome core. As a result, the wire has a cross section of about 7 mm. You can't cut the vein. It is connected to the wire for connecting to the network with special soldering. It is almost impossible to make it qualitatively at home. The warranty for the cut wire is not covered in this case.

The resistive wire heats up to its maximum value in a certain amount of time. To be able to control the rate of thermal energy, you need to use a thermostat. Otherwise, the system will consume a lot of electricity.

Disadvantages of resistive wire

Roofing with resistive wire has a lot of disadvantages. The presented system, as mentioned above, heats up equally along the entire length. In this case, a situation may arise when the temperature on one side of the roof is higher. This is where the cable will overheat. Over time, the system will fail.

This is not the only disadvantage of constant heating wires. This system cannot be shortened. The size of the gutters, the area of ​​​​the roof can vary significantly. At the same time, it is difficult to choose the exact size of the cable for heating.

As a result, the lifetime of the presented system is significantly reduced. During installation, you will need to purchase a thermostat separately. Its cost is 5-8 thousand rubles. Without the inclusion of this additional element in the network, the system consumes a large amount of electricity.

Self-regulating wire

The self-regulating heating cable is a more advanced system. It consists of two metal wires through which electric current is supplied. Between these conductors is a special material. It is a semiconductor that reacts to the ambient temperature. When it gets cold outside the window, it freely passes current. In this case, the system heats up more. If it gets warmer outside, the internal matrix of a special polymer will become worse at conducting current. In this case, the heating will be less.

The internal matrix with conductors is surrounded by special insulating materials. This system can be connected directly to the network without a thermostat. It will consume only the required amount of electricity. At the same time, in severe frosts, the heating will be stronger, as well as the need for energy resources.

This wire is divided into small sections along its entire length. Therefore, it can be shortened. This allows you to mount the system exactly on the usable area.

Benefits of self-regulating wire

And roofing with self-regulating wire has a lot of advantages. Due to the absence of overheating, the system is highly durable. It is also used to prevent freezing of water and sewer pipes. The wire clearly responds to environmental conditions.

When installing the system, you do not need to buy an expensive thermostat. You only need to mount the plug on the lead wire. It is connected to a normal household network. This makes the system easy to operate. The owners of the house do not need to monitor the indicator of the outdoor thermometer. The system regulates heating independently.

The only reason why the presented type of wire is not yet used for outdoor heating everywhere is its high price. Resistive wire from each manufacturer is cheaper. Therefore, many owners of private real estate choose this type of wire, despite all its shortcomings.

Installation of the system on the roof

equipping electrically heated roof design must be taken into account. If there are no gutters on the roof, one of two installation schemes can be used when installing the cable. The wire is laid out on special guides. Most often they are supplied with a wire. If they are not available, you can purchase a mounting kit from specialized stores.

If there is no drainage system on the roof, and its slope is small, you can make a system with a recess in the center. It is equal to 40 cm. The wire enters this funnel.

If the slope of the roof is steep, the system unfolds from the center to the edges. Near each corner, it is necessary to cut holes through which loops of wire and melt water will exit. For these purposes, a wire of 40-60 W / m is suitable.

Installation of wire in the drain

Most often, self-regulating heating cable. In this case, it will be necessary to install a cable at the bottom of the pipe for 2/3 of its length. It is fixed with the help of special mounting elements. The wire is laid in several rows (depending on the width of the drain).

The more the colder it is outside in winter, the more power the system should be characterized. The distance between the wires is selected in accordance with the manufacturer's recommendations. The average distance is 5-7 cm.

If a resistive cable is used for installation, please note that it must not be bent too much. Otherwise, the inner core may be damaged. The minimum pitch between the turns of such a wire is 5 cm. The cable should not cross, its threads should not pass close to each other. Otherwise, the system will overheat.

Combined system

Many construction organizations and professional roof heating installers recommend using two types of wire at once. For this case, a self-regulating cable is selected. The remaining parts of the roof can be heated using a resistive variety.

This solution makes installation cheaper than using only self-regulating wire. The quality of heating and the durability of the anti-icing system will be higher than when using only resistive wire. At the same time, electricity bills for home owners will be optimal.

Having considered how to create roof heating, you can independently select and install electrical wires in accordance with established building codes.

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