How are sewer pipes insulated? Insulation of sewer pipes of external sewerage. Ways of insulation of sewer communications
Engineering Communication country cottages in winter they are easily frozen. Which does not add comfort to the inhabitants of the house, but brings a lot of trouble. It is quite possible to prevent this phenomenon on your own.
Methods for insulating a sewer pipe in the ground
Freezing drains are a fairly common occurrence. The most dangerous and freezing-prone part of the pipe is the part that leaves the house, or is located not very deep underground. Of course, all this is desirable to take into account even at the construction stage. But laying pipes below the freezing level can be difficult. Especially when the trench is more than one meter deep, or the groundwater is high enough. In this case, the insulation sewer pipes in the ground may require increased financial costs.
The main methods of insulation include:
- Insulation shell made of expanded polystyrene (aka polystyrene);
- Warming outdoor sewerage heating electric cables;
- The use of a variety of heat-insulating structures;
- Use of several options for insulation at the same time.
Before choosing the type of insulation, it is necessary to analyze the features of the climatic zone in which the house is located, the required labor costs, as well as the type of pipeline laying.
When choosing how to insulate sewer pipes in the ground, you should pay attention to the environment and the weather. Warming in the south of the country is not relevant. The pipeline is simply laid to the required depth. Sometimes it is wrapped with thin insulation, but thermal insulation in such a region almost always turns out to be an extra waste.
AT northern regions the heat-insulating layer of the pipe should not be thinner than 10 cm. And for such a design, a protective box is required.
How to choose a heater
When applying insulation, you should try to choose the material that is optimal in its properties, taking into account the characteristics of the soil in which it will be laid.
In general, the types of heaters can be divided into several groups:
- Bulk;
- Roll;
- Plate-sheet;
- Foam blocks.
When using the first type, the pipeline laid in the trench can simply be covered with expanded clay. This method of insulating sewer pipes in the ground with your own hands is the simplest and most inexpensive, but it will only work if the trench is dry. With roll and slab types of insulation, a protective waterproofed box is required. This is necessary to prevent the formation of ice plugs in cold winters.
High-quality insulation of external sewer pipes is due to well-chosen material. The range of thermal insulation materials for sewer pipes on the market is very wide and it is not so easy to make a choice. But what you definitely need to pay attention to is that the insulation is already waterproofed. In this case about additional measures you won't have to worry.
Characteristics of some thermal insulation materials
Common heat-insulating materials include: polystyrene foam, foam plastic, mineral wool, isolon and HDPE.
Styrofoam- a material with low thermal conductivity, consisting of polystyrene foam granules pressed together. This insulation for sewer pipes in the ground is quite easy to equip. The foam shell can be selected exactly according to the diameter of the pipes, and it is equipped with special groove fasteners. Before laying, the foam cylinder is put on the pipeline segment and secured with clamps or special tape. Doing it yourself will not be difficult.
Pros of foam:
- environmental friendliness;
- long term services;
- ease of operation and repair, during installation and dismantling;
- resistance to aggressive influences external environment;
- inexpensive price.
Fully waterproof to prevent moisture from getting inside. So polystyrene is universal as thermal insulation.
Penoplex- another way to ensure the insulation of sewer pipes in the ground suitable for self-assembly. This foam material is able to withstand very high loads. Penoplex is suitable for outdoor and underground use, and does not depend on the properties of the soil, as it does not rot in the ground.
In addition, penoplex has a long service life, is able to work with high humidity(having almost zero water absorption) and does not react when interacting with building materials (except for acetone). Like polystyrene, it is environmentally friendly and fire resistant. But in comparison with foam plastic, foam plastic demonstrates better thermal conductivity and more high strength with a minimum specific gravity.
Technological mineral wool- a proven method for someone who solves the problem of how to insulate sewer pipes in the ground and save money at the same time. Glass wool is popular due to its good resistance to vibrational loads.
In addition, due to the fibrous structure, it has a low thermal conductivity. Technological wool, in itself, is a rather cheap insulation, but when working with glass wool, you need to protect it from moisture with something, for example, with a layer of foil.
The main advantages of glass wool:
- Noise insulation of sewer pipes (read also: "");
- Chemical and biological resistance;
- Affordable price;
- Plastic;
- Elasticity.
glass wool, basalt wool . Insulation from such wool can be given any shape and, as a rule, it provides its own layer of waterproofing.
- incombustibility;
- hydrophobicity;
- Long service life;
- Resistance to corrosion and the effects of fungi and mold;
Foil isolon- a fairly popular material that has good resistance to moisture and bacteria (more: ""). It is easy to use - the material is cut into narrow strips, with which the pipe must be wrapped in a spiral.
Positive properties of isolon:
- High elasticity;
- Light weight;
- Resistance to chemical and biological influences;
- Possibility to choose different material thickness.
Roll insulation penofol is a foil with a layer of polyethylene foam applied. Can act as the main insulation and as an interlayer thermal insulation system. Compared to other materials, this one is very thin and has significant flex under pressure. But, despite this, it has good waterproofing performance.
The method of pipe insulation using an electric cable
When choosing how to insulate a sewer pipe on the street, it is recommended to pay attention to a modern and highly effective method that has won many good reviews. These are insulated pipes for sewage using electricity. Relevant in areas where the temperature in winter period it can be less than -15 degrees C. The cable can be passed both over the pipe and inside it, after which it is connected to the network through the machine. The cable will allow you to warm up communications in any weather.
The cable is laid along the entire pipeline and fastened with aluminum tape, after which the structure is wrapped with a layer of heat-insulating material. Wherein plastic pipes before laying the cable, it is recommended to wrap it with foil, for even distribution of heat. With metal pipes it's not needed.
When insulating pipes in this way, it is worth taking care of autonomous sources of electricity, a spare generator in advance.
There are several types of heating cables:
- Resistor with thermostat;
- Self-adjusting with auto-on;
- Zonal - for local sewerage sites.
The first option is cheap in itself, but when used, power consumption will increase significantly, which is not the most in the best way affect the budget of residents. In the future, a self-regulating cable will be more profitable.
It automatically regulates the supply of electricity depending on the ambient temperature, eliminating overheating or freezing of the system. But in any case, insulation with an electric cable will entail significant investment.
Stages of insulation of sewerage in the ground
The first step is to prepare the trench. At the same time, the depth should be 10 cm more than planned, in order to create a shock-absorbing cushion from compacted sand.
The external sewage system itself is assembled on the surface, and insulated there.
But initially, the joints of communications are smeared with sealant in order to prevent the appearance of gaps. Next fit waterproofing materials, but if the material has its own waterproofing, this is not required. Otherwise, it makes sense to use polyethylene film or foil.
The foam shell is fitted onto the pipes and fastened with aluminum tape. For fixing technical wool You will need construction tape. Both materials are located with a moisture-proof layer outside.
If applicable electrical cable, first, the waterways are waterproofed, after which an electric wire is attached to the pipe, with one or more threads. Can be mounted along the bottom of the pipe, or wrapped in a spiral. A layer of heat is placed on top insulating material.
When insulating, it is important to ensure that the material is laid as tightly as possible. This is necessary in order to avoid possible deformation and damage due to ground movement.
After everything is done, the system is laid in a trench with the provided slope. Usually the slope is 1-2%. The smaller the slope, the more reliable the insulation material should be. The pipe is covered with a protective layer of sand, but it is compacted only on the sides, this is not necessary above the pipe itself, so as not to damage the pipe itself.
The last stage is backfilling the trench with soil. It is better to do this with a margin (create a mound), since the soil will inevitably settle over time.
By combining several types of insulation, you can achieve perfect result. And although not all installers consider complex insulation procedures mandatory, it is better to invest in initial stage than to waste energy and money later, endlessly repairing the system.
A complex device for thermal insulation of sewer pipes in the ground will be more expensive, but will justify itself in the future and guarantee comfort and peace of mind to residents.
It is clear that nothing good can be expected from the freezing of a sewer pipe on the street. At the primary stage, an ice plug is formed that prevents the passage of wastewater. As the situation worsens, the blockage will increase in volume, and eventually completely close the passage. In this case, there is only one way out of the situation - sewer pipe repair, with partial replacement, the failed section. And this is earthworks, and additional costs.
There are opinions that in a private house, thermal insulation of a sewer pipe passing on the street in the ground is not needed. Ridiculous opinion, and more senseless excuse - wastewater, are characterized by a positive temperature and do not have time to freeze on the way from the house to the septic tank.
To some extent this is true, but as practice shows, in a private house, a sewer pipe freezes no less than in general house networks. Therefore, thermal insulation is essential. It’s easier to spend money on carrying out related work once, and secure the system in case of unforeseen situations.
Important! The optimal solution there will be thermal insulation of sewer lines in the process of laying the system than subsequent refinement if a defect is identified.
What parts of highways require special attention?
When insulating a pipe laid in the ground, it is important to isolate the entire line. But the following areas deserve special attention:
- places for drains from the house to the street;
- connecting the line to each other and the junction with vacuum pumps;
- leads to a common discharge system.
If, during isolation, you pay special attention to these places, and properly organize protection from the cold in the ground, you can not think about the quality of the functioning of the sewer, even in the most severe cold.
Three ways to insulate pipes from the cold
To solve this problem in a private house, there are three effective options, the implementation of which will reduce the effect of cold on the sewer pipe:
- laying below the freezing level of the soil;
- insulation modern materials;
- heating cable laying.
by the most simple option, not requiring special costs, will be the first way. The pipeline is laid below the soil freezing level by 15 cm. But in this case, it will be problematic to withstand the slope of the sewer pipe, especially if general system located on close range To home.
If you look from the financial side, then you do not need to purchase any heaters. But, having considered the “deeper” option, you can find a lot of negative sides.
The first is the great depth of digging a trench in the ground. Let's take a temperate zone as an example. According to Russian standards, the average depth of soil freezing is 150 cm. minimum score for laying a sewer pipe in a private house - 160 cm. And this is without taking into account the slope. As a result, the final section will have to be immersed in the ground by at least 2.5 meters, with a relatively large length.
The second is the difficulty of repair. Nothing on earth lasts forever, and even the sewer system, laid out according to all the rules, will someday require repair. This may be a consequence of the use of substandard pipes, or the result of a dishonorable attitude of family members. This may be an unintentional act, such as a prank by a child throwing a washcloth down the toilet.
Cleaning the drain won't help. Unless, if the blockage occurred not in the ground, but in the connecting elements in the house. This is the best outcome, at worst, you will have to "raise" the ground and look for a blockage.
Based on the foregoing, it can be stated that the option of deep laying a pipe in the ground is possible only if there are no obstacles, with technical side. In other situations, it is necessary to look for a more rational solution.
The best insulation for sewerage - shell, mineral wool and other materials
Without considering the simple option of insulation, which turns out to be difficult during operation, you can “go” the other way and isolate the sewer in the ground with modern materials, which are plentiful on the construction market. One of the novelties that stands out in terms of efficiency is the isolation of highways using PPU shells.
The installation of such an insulating material in the sewer system is carried out as follows:
- an insulator is selected identical to the diameter of the pipe;
- the entire highway is closed with shells, with an overlap of up to 20 cm;
- the joints are additionally insulated with reinforced tape.
The work is done, it remains only to fill the sewer pipe with soil. The scheme is deceptively simple.
The depth of laying the sewer pipe in this case does not play a role. The insulation will reliably protect the highway in the ground. It is enough just to properly isolate it and sprinkle it with at least a little earth.
On a note. Industry offers shaped shells different diameter and length. There are also on sale elements for isolating folds and transitions, so there will be no problems with the choice of components.
No less relevant in solving the problem and other types of modern insulators for a sewer pipe in the ground.
Foamed polyethylene - reliable protection from the cold
Heaters based on this material are produced in the form of tubes of various diameters, which you just need to put on the insulated area. But the disadvantage of this product is its low density. Therefore, it is not suitable for insulating pipes in the ground. Only for insulation of highways in the basement.
Mineral wool in the insulation of sewer pipes
This material is the progenitor of all existing market segments today. Until a certain time, it was the only insulator used for such purposes. But today, modern heaters have “pushed” it off the market. The rating downgrade occurred on the following points:
- firstly, mineral wool is extremely uneconomical as a heater for water and sewer pipes;
- secondly, mineral wool is hygroscopic, which indicates the need for additional waterproofing.
Important! Using mineral wool it is necessary to additionally isolate the material from moisture. If this is not done, the properties of the insulator will be reduced to zero by groundwater.
Penoizol as one of the best insulators
This is a liquid filler applied from special installations to pipes. When solidified, it creates a reliable barrier to cold, and thanks to the hermetic shell, it is completely “indifferent” to manifestations of moisture.
But in a private house it is rarely used. Due to the complexity of acquiring equipment. More often, specialized companies do this, and many are deterred by the cost of the work.
Insulation of a sewer pipe with a heating cable
The heating cable for sewer pipes works according to an autonomous scheme. Actually, there is no division into use with respect to one system. The equipment is simply purchased and laid according to the scheme. The cable is laid inside the pipe or mounted on top of it. According to the type of operation, there are two types of heating cable:
- self-regulating;
- normal.
The first option is expensive, but its job is to save energy costs. Sensors installed along the entire length of the pipeline turn on heating only in those places where the temperature drops below the specified parameter. The usual system, works autonomously, and heats the entire pipe. But it can be turned off for a while, for example, when the weather is not very cold outside.
Heating cables provide 100% protection of the sewer pipe in the ground from freezing, while local methods such as installing insulators may not be able to do the job. This is explained by the properties of soil heaving. In the presence of groundwater, the soil layers can shift, thereby "taking away" the insulator from the main. And although the displacement will be non-critical, the constant exposure to low temperatures will affect the quality of the insulation, deteriorating performance.
It's no secret that in winter, uninsulated sewer pipes often freeze, their walls burst and the sewer system breaks, which immediately creates emergency.
And then, unfortunately, it is very difficult to produce land and repair work at sub-zero temperature and frozen ground.
In order to insulate pipes in a timely manner, you need to know what heat-insulating materials exist that are suitable both for outdoors and for laying underground, what types of insulation exist and to prevent freezing of sewer pipes, as well as how to do all the work of insulating pipes of the outer part of the sewer.
Those who do not insulate the sewer pipeline in the outer part of the network are at risk of repairing the sewer in the winter.
However, there is an opinion that due to the wide, normal speed flows of sewage and hot or warm household drains, sewerage cannot freeze in winter.
And, nevertheless, experts do not recommend relying on the Russian "maybe" or the opinion of those who, perhaps, winters are simply not as severe as in other regions of Russia, but to insulate sewer pipes immediately when they are laid during the construction of an autonomous sewer system.
Indeed, in some regions, it is enough for the thermometer to show a minus, so the sewer pipes immediately begin to freeze, which is why repairmen have to fight in the winter.
At a large minus temperature, and even if a blizzard or strong wind, sewer pipes instantly freeze through, forming ice growths inside the sewer network.
Meanwhile, people continue to use the sewer, the drains also continue to fill the frozen pipes and, thus, the liquid entering the sewer system turns into ice, which completely fills the entire space in the pipe.
Accordingly, the ice expands the capacity of the pipe, which breaks through and creates an emergency situation in the pipeline sections of the sewer system, which is not so easy to solve in the winter.
Usually, several methods are used to deal with breakthroughs and prevent freezing of sewer pipes in winter:
- deepening of the pipeline to a depth below the freezing of the soil;
- insulation with special heat-insulating materials;
- heating with a special electric cable.
The fact is that experts know one secret regarding soil freezing, and it lies in the fact that the temperature of the soil at a level below the freezing point is always almost the same and ranges from 10 to 12 degrees Celsius, which is considered the most optimum temperature in order for sewer pipes to function in the ground without insulation.
However, most non-professionals miss this factor and lay pipes above the freezing level of the soil without insulating the pipes in any way, as a result of which the sewer breaks in the winter and the entire system fails.
Deepening is especially true for those sewer systems that do not serve the family all the time and there are periods of system downtime in operation.
Photo: sewer deepening In the case of insulation, the pipes must be carefully wrapped with a suitable heat-insulating material. It should also not be forgotten that any heat-insulating material has nothing to do with heating.
This means that any heat-insulating material only slows down the cooling of the pipe or the outflow of heat.
When laying pipes that will serve sewers in soils with a risk of freezing, it is recommended to make a sufficient slope of the pipes (more than 20 mm per 1 running meter pipeline), as well as lay a heating electric cable outside the pipe.
Otherwise, even if you wrap the pipe with insulation, someday it will still freeze, and the drains that continue to flow into the pipe will create ice jams, which subsequently will lead to pipe rupture and system downtime.
The next point, which also cannot be overlooked, is the insulation of the ventilation sewer pipe.
Just such pipes are located on the surface: some are brought to the roof and go from sewer riser, while others come out of the ground, ventilating a septic tank or some treatment plant or located underground.
Evaporation from sewage, as a rule, is wet, and therefore, settling on the walls of the pipe, it can gradually create an ice or frost cover, which will significantly reduce the clearance inside the pipe and clog the ventilation system.
In turn, the residents of a house with such clogged ice or frost ventilation system, will soon begin to feel unpleasant odors emanating from all plumbing fixtures.
Photo: sewage fumes settle on the pipe walls To correct the situation in case of freezing of the ventilation pipe, it is necessary to pour a bucket of boiling water into the riser, on top of the ice plug. Then you can only wrap ventilation pipe any heat-insulating material or lay an electrical cable that has a heating function.
Important! Of course, the cable must be isolated from the external environment, after laying it in a corrugation or a narrow plastic pipe. All these measures must be applied if you want to keep your sewer system running as long as possible.
It should also be noted that there are certain factors that can influence the choice of insulation method:
- if your house with a sewer is located on the Black Sea coast, then the sewer is insulated, only on its horizontal sections, wrapping it with a small layer of thermal insulation;
- but if you live in Siberia or the far north, in Yakutia or Yamal, for example, then sewer pipes are laid in a special box with a thick layer of foam that will run around the pipe.
Thus, the location in a particular region of the whole country plays a significant role in the application of one or another method of insulation.
After all, freezing of the soil in different areas is different from each other. In Crimea, if there are frosts, they are short-term, and the lowest temperature in the coldest month of winter here barely reaches zero.
Accordingly, in residential areas in the far north, the lowest temperatures reach -50˚С.
Photo: soil freezing in different areas If we are talking about an external sewer pipeline that is laid in the ground, then it is insulated taking into account certain conditions and cases:
- special attention during insulation is given to various turns, drops or adapters on the sewer route;
- the depth of laying pipes is less than the depth of freezing in a particular area;
- the slope of sewer pipes is minimal - less than 2 cm per 1 linear meter of pipes;
- the slope of the sewer pipes is maximum - more than 2 cm per 1 linear meter of the route;
- with frequent blockages in pipes;
- with certain characteristics of the material from which sewer pipes are made - for example, not all metal or plastic pipes freeze through, especially if their wall thickness is large enough.
Therefore, all sewer pipes suitable for these features are subject to insulation or heating.
In addition to sewer pipes laid underground, special attention is required in the thermal insulation of pipes that pass above the ground.
All pipe systems that run on the surface of the earth are installed in this way, most often due to the lack of the ability to carry out earthworks.
These are either permafrost soils, or rocky soils, where it is not possible to make trenches of the required depth. In such cases, the pipeline passes above the ground, which also implies its insulation.
Photo: insulated pipes For sections of sewer pipes that are located in the basements of residential multi-storey buildings, insulation of the pipeline is the first necessity.
The fact is that basements, as a rule, are not heated, and therefore the pipes passing there need thermal insulation no less than external sewer pipes.
After all, how many emergency cases have already been recorded by the repair services, when not only water pipes, but also sewer pipes broke through in the winter period precisely in basements multi-storey residential buildings.
Therefore, the insulation of sewer pipes in basements is also one of the types of thermal insulation and covering of sewer pipes.
Photo: basement of a high-rise building In other words, it can be adopted that all sections of the pipeline of a particular sewer that fall on the outer part of the sewer, whether it be underground, ground or basement communications, need to be properly insulated or even heated.
Otherwise, in the winter, any section of the external sewage system will show itself not with better side, pipes will constantly break through, and repairing them in winter is a rather laborious and expensive pleasure.
Thermal insulation materials and external sewerage
For thermal insulation works it is necessary to stock up on the necessary and suitable thermal insulation materials.
Not every material is suitable for a particular pipe, and not every method of insulation may be suitable for certain sections of the sewer line.
Among all possible ways insulation of sewer pipes, most often, thermal insulation is used different types, types and parameters.
Materials for pipe insulation are:
Styrofoam
This is a modern common material for thermal insulation. Due to the fact that its structure is strictly granular, holding long time required pipeline temperature.
In addition, Styrofoam can be reused, which increases its operational terms.
Photo: polystyrene foam Styrofoam
This is one of the subspecies of expanded polystyrene, which is also granulated, but only slightly compressed on both of its surfaces. Its granules are also waterproof, which is very important for insulation.
Most often, foam is used in special boxes for laying and thermal insulation of sewer pipes.
Photo: foam Basalt fiber
This rolled heat insulator is similar to cylinders, which are made from special fibers that retain heat.
Its only drawback may be its high cost, but otherwise such a material as heat-insulating has some advantages.
Photo: basalt fiber Glass wool or mineral wool
Most of all, it is considered a practical material because it performs its heat-insulating functions, and, at the same time, is very cheap.
The disadvantage of this material is the need for waterproofing. After all, wet construction wool conducts heat very well, and such characteristics significantly reduce its value as a heat-insulating material.
Important! Therefore, mineral or glass wool must be wrapped on top with waterproofing material.
Photo: glass wool or mineral wool Foamed polyethylene
Such a heater is perfect for insulating sewer pipes in a warmer climate zone because it is thin, but warm in itself, you can especially feel it if you touch it with your hand and hold it for 30 seconds.
For insulation of the sewer pipeline in frosty areas. Such a heater will need to wrap the pipe in two or three layers. Also, this insulation does not allow moisture to pass through and is very resistant to moisture.
It can be used many times. The only drawback may be thinness and fragility - it breaks very quickly, so it is recommended to work with it carefully.
On the market, foamed polyethylene is sold as a rolled sheet or light tubes of different diameters.
Photo: polyethylene foam Penoizol
A material for specialists and professionals, which is often used in the construction of large-scale sewer systems of central city communications as a heat-insulating material.
Important! This material must be sprayed, covering the entire surface of the pipe with an insulating layer. Similar thermal insulation material such as polyurethane foam or polyurethane foam, belongs to the most expensive species materials because it is sold in small cans, which require a lot.
The advantage of these materials is that they are very resistant to low temperatures, do not require that any additional fasteners be used during the installation of the foam, does not transmit heat.
Photo: penoizol Penofol
This is a foil on which a layer of polyethylene foam is applied. Two tasks are solved here: thermal insulation and waterproofing.
Such a material is suitable not only for reflecting heat or light, but also for retaining the heat of a sewer pipe in winter;
Photo: penofol Expanded clay
Bulk material, which also refers to thermal insulation. However, in addition to these properties, expanded clay is also an excellent filter that does not let heat through while "breathing".
Therefore, when laying pipes in the ground on a pillow of expanded clay, first of all, you need to pay attention that the trenches are dry without groundwater, otherwise the expanded clay in the water will not realize its properties.
Photo: expanded clay When choosing a heater, a number of promising points and factors that you should pay attention to are very important:
- low weight insulation;
- high thermal insulation properties;
- ease of installation or application of insulation;
- environmental Safety;
- maximum long service life;
- acceptable cost of insulating material;
- strength and stability of the material;
- inertness to the effects of chemical and biological aggressive environments in the composition of the soil solution (all heaters, which include cellulose, are not suitable for insulating sewers underground or on the surface);
- high degree of adhesion of the insulating material - adhesion of dissimilar materials;
- waterproofing;
- fire safety.
Thus, we have presented you with heat-insulating materials that are the most profitable and best used, according to experts, when insulating sewer pipes, wherever they are located.
With the help of heaters, a number of works are performed that differ from each other. So, there are rolled heaters that can be wrapped around pipes, and there are heaters in the form of tubes that are easily cut.
There is also a whole range of insulation options in the form of flexible and elastic plates that are easily wrapped around pipes and tied with reinforcing cables, nylon ropes or wire.
Foam insulation, pieces of cotton wool, as well as bulk material - expanded clay are also interesting.
Video: how to insulate and heat a pipe
Active insulation
Some options for pipe insulation do not cease to amaze with their technologies and engineering solutions.
So one of these options is active insulation, which is very appropriate and applicable when thermal insulation of sewer pipes is used in the ground, outside or at insufficient depth or with insufficient slope of the sewer pipeline.
Active insulation is a method of heating sewer pipes using a heating cable, which is powered by electricity.
Such pipes are laid in the ground, installed on the surface, in basements or located in special boxes. Of course, the installation of such a pipe heating system is quite laborious and costly, but in some situations it is simply impossible to do without it.
The downside of such insulation or heating is complete energy dependence on electricity, so it is desirable that such a sewer system is always connected to electricity in the winter.
If the pipe is in the ground
The most natural way to insulate sewer pipes in the ground is to bury them to a depth that is below the freezing depth of the soil in the area where the sewerage runs.
It is precisely due to the fact that the same positive temperature is maintained at a depth below freezing, the pipes do not need to be specially insulated, it is enough just to lay them on a crushed stone pillow, sprinkle with a dry mixture of sand and cement and cover with soil, tamping lightly.
However, there are also disadvantages here. In case of any breakdown of the sewer pipeline, not even due to freezing, but, for example, due to blockages, the entire route will have to be dug up again, repaired, and then deepen and level the ground again. It is because of the complexity that deepening is not always considered appropriate.
Photo: laying pipes to a depth below freezing of the soil The next, radically different from all other methods, can be called the heating of the sewer pipe with an electric cable.
Such a heating technique, of course, financially has its own costs for the acquisition of the system, installation and further operation, but it fully justifies itself.
Winding pipes with an electric cable for heating the sewer system in winter is often used for a pipeline route that is not deep enough, for example, due to high level groundwater, installed pipes on the surface of the earth, as well as in basements and other unheated premises.
The winding of pipes passing in the ground with an electric cable must pass along the entire perimeter or over the entire surface of the pipes and have a reflective film.
Photo: heating the sewer pipe with an electric cable But the most economical, less financially costly and more easy option insulation of sewer pipes in the ground, all the same, is their wrapping or shelter with heat-insulating materials.
To do this, trenches for laying pipes are prepared wider than pipes, any winding with thermal insulation materials must be strengthened and fixed with adhesive tape or wire, depending on the type or type of thermal insulation.
Important! It is also very important to protect some heaters from moisture. Other subspecies of thermal insulation can simply be put on the pipe, while maintaining integrity. All insulated pipelines are best laid in a trench on sand cushion.
Photo: shelter with thermal insulation materials In addition to the above basic methods of insulating sewer pipes in the ground, a combination is often also used. Most insulation methods can be combined.
So, for example, insulated pipes with heat-insulating material can be laid on an expanded clay pillow, while sprinkling pipes with expanded clay.
Such a combination will double the thermal insulation properties and keep the entire pipeline system from freezing in winter, no matter what the temperature fluctuations are. After all, it's no secret to anyone that winters are different, and frosts in temperature conditions differ from year to year.
Therefore, the combined method will be most beneficial for the further safety of the sewer.
How to insulate a pipe on the street
If it is not possible to deepen the sewer pipe, or lay it at least for minimum depth in a dug trench, then a ground sewer pipeline network is used.
Such systems are found in permafrost regions, advanced level groundwater, as well as where rocky ground prevails.
Most effective way insulation of sewer pipes on the street is precisely the combined method of insulation.
Important! And not only should two or three types of thermal insulation material be combined, but it is best to also use a heating cable powered by electricity.
The cable itself, of course, has insulation, but to improve it and strength, the cable must still be protected from the outside.
There are three types of such cables:
- self-regulating;
- resistive;
- zonal.
Self-regulating electrical cable is just a godsend for owners autonomous sewerage with its outer sections above the ground or on the ground.
After all, it is reliably protected from overheating, while it can be constantly connected to electricity and have amazing thermal conductivity.
Its feature is that it adapts to temperature fluctuations, reducing its resistance when the air temperature rises and increasing its resistance when the air or ground temperature drops.
Photo: self-regulating cable design A resistive cable, on the contrary, must be installed with additional temperature controllers, otherwise its breakdown will not be long in coming.
Although it cannot independently adjust to temperature fluctuations, its use as a heating of sewer pipes is considered the cheapest and best way.
Zonal cable is used exclusively for small sections of the pipeline, therefore, for heating pipes on the street, such a cable is needed insofar as.
Most likely, it will be useful in sections of the sewer pipeline passing in the basement.
Important! One winding of sewer pipes with an electric cable is not enough for their insulation. After you have wrapped the cable and checked its operation, you should continue the thermal insulation with special insulation materials in several layers.
This will significantly increase the operational life of the entire sewerage system in the winter.
There are several ways to attach and install the cable to the sewer pipe:
- one-sided straight-line installation of the cable to the pipe (Fig. 1);
- double-sided straight-line installation of the cable to the pipe (Fig. 2);
- spiral winding of the cable along the surface of the pipe (Fig. 3).
Photo: ways to attach and install the cable to the sewer pipe The distance between the fasteners when fixing the electric cable to the surface of the sewer pipe must be observed not less and not more than 200 mm.
Ordinary adhesive tape should not be used here, because from heating the cable and contact with it, simple adhesive tape will simply melt.
To install the cable on the sewer pipe, the following fasteners are used:
- special synthetic bandage for cable;
- special steel cable tie (only for electrical cables with mineral insulation);
- heat-resistant adhesive tape;
- tie tapes.
These materials are easy to purchase in the same store as the cable. The most important rule during installation for sewer pipes is to prevent the cable from crossing when it is laid.
Most often, such heating is laid with outer surface sewer pipe, but there are options for laying the electric cable inside the pipes, which is much harder to do.
If in your area the frosts are not so strong in winter, but there is no way to dig trenches, then you can use ordinary foam materials without laying a cable.
Therefore, in the case of outdoor sewage on the street, you need to think carefully about its insulation, focusing on frosts in winter in your region or region.
How to do it yourself
When laying sewer pipes in the ground, it must always be observed. The choice of insulation directly depends on this. The smaller the slope, the more reliable the pipe insulation should be.
Important! The standard slope is 2 cm per 1 linear meter. If you make it smaller then sewer drains will slowly flow, which will increase the rate of their freezing inside the pipes.
Therefore, this moment should be taken into account immediately when digging trenches and laying pipes.
If for some reason you do not have the opportunity to make a sufficient slope of the sewer pipes, for example, if too small plot and the pipeline is short, then the thermal insulation method can be used active heating using a cable.
However, the most optimal and simplest is all the same, the deepening of sewer pipes in trenches with wrapping them with heat-insulating material.
For insulation, it is very convenient to use the simplest materials and items that may be needed in the work procedure:
- foam shells;
- self-adhesive aluminum tape;
- stationery knife.
Photo: foam shell Styrofoam shells have peculiar locks, with the help of which they perfectly join each other, wrapping the pipe and adhering tightly to it.
The shells are already laid on the assembled and finished sewer pipeline, wrapping it from all sides. With a clerical knife, the shells are cut exactly to the distance necessary for easy installation.
All tightly packed foam shells are fixed with aluminum adhesive tape. As you can see, the installation of foam insulation is very simple and easy to do with your own hands.
Prices for insulation materials
Each type of insulation for sewer pipes has a completely different characteristics, which distinguish them from each other not only in terms of texture, thickness, length, number of meters per roll or volume in a can, but also in terms of cost.
Moreover, each manufacturer in any region presents its product according to different price, with different conditions purchases and privileges for its regular customers.
And, nevertheless, despite the difference in cost for different heat-insulating materials for sewer pipes, you can find average data on the prices of different categories of heaters.
Today, the market offers a very wide range of such product groups. Moreover, such heat-insulating materials insulate not only sewer pipes, but also the roofs of houses, from the side of the attic, house walls, floors, doors, plumbing and other areas of residential buildings.
| Name, brand of heat-insulating materials and fasteners for them | Width, mm | Length, m.p. | Diameter, mm | Quantity | Price, for 1 piece, for 1 sq.m. or for 1 running meter |
| Teploflex NPE | 1,05 | 50 | — | 52.5 sq.m. | 7 |
| 1,05 | 50 | — | 52.5 sq.m. | 13 | |
| 1,05 | 50 | — | 52.5 sq.m. | 29 | |
| 1,05 | 25 | — | 26.25 sq.m. | 32 | |
| 1,05 | 50 | — | 52.5 sq.m. | 35 | |
| Teploflex C | 1,0 | 50 | — | 50 sq.m. | 47 |
| 1,2 | 60 sq.m. | ||||
| 1,0 | 15 | — | 25.30 sq.m. | 66 | |
| 1,2 | |||||
| 1,0 | 15 | — | 15 sq.m. | 139 | |
| 1,2 | 18 sq.m. | ||||
| Teploflex C | 1,0 | 2,0 | — | 2.0 sq.m. | 73 |
| 1,2 | 2,4 | 2.88 sq.m. | |||
| 1,0 | 2,0 | — | 2.0 sq.m. | 121 | |
| 1,2 | 2,4 | 2.88 sq.m. | |||
| 1,0 | 2,0 | — | 2.0 sq.m. | 195 | |
| 1,2 | 2,4 | 2.88 sq.m. | |||
| Thermal insulation cylinders made of mineral wool | — | — | 18 | — | 67 |
| — | — | 21 | — | 100 | |
| — | — | 25 | — | 143 | |
| — | — | 28 | — | 181 | |
| — | — | 32 | — | 237 | |
| — | — | 35 | — | 300 | |
| — | — | 45 | — | 407 | |
| — | — | 48 | — | 107 | |
| — | — | 54 | — | 140 | |
| — | — | 60 | — | 192 | |
| — | — | 70 | — | 266 | |
| — | — | 89 | — | 379 | |
| — | — | 114 | — | 520 | |
| — | — | 159 | — | 735 | |
| — | — | 18 | — | 83 | |
| — | — | 25 | — | 126 | |
| — | — | 35 | — | 160 | |
| — | — | 45 | — | 228 | |
| — | — | 57 | — | 324 | |
| — | — | 70 | — | 487 | |
| — | — | 108 | — | 630 | |
| Penofol with double-sided foil | 1,2 | 25 | — | 30 sq.m. | 2550 |
| Penofol foil | — | — | — | 18 sq.m. | 1045 |
| Self-adhesive penofol | 0,6 | 15 | — | 9 sq.m. | 2350 |
| PE foam insulation pipe | 1,2 | 50 | — | 60 sq.m. | 47 |
| 1,2 | 50 | — | 60 sq.m. | 49 | |
| 1,2 | 25 | — | 30 sq.m. | 66 | |
| 1,2 | 15 | — | 18 sq.m. | 93 | |
| 1,2 | 15 | — | 18 sq.m. | 140 | |
| Adhesive for polyethylene foam | — | — | — | 1 l | 270 |
| Reinforced adhesive tape, gray | — | — | 50 x 50 | 1 PC. | 140 |
| Clamps plastic | — | — | — | 100 pieces. | 257 |
| Aluminum tape self-adhesive | — | — | 50 x 50 | 1 PC. | 406 |
| Technical thermal insulation, mat | 1000 | 4000 | — | 1 PC. | 1237 |
| 5000 | |||||
| Liquid thermal insulation, penoizol | — | — | — | 1 PC. | 1300 |
| 1800 | |||||
| Basalt fiber, stitched mat | 1000 | 500 | — | — | 1600 |
| 6000 | |||||
| Styrofoam shells | — | — | — | 1 PC. | 195 |
| — | — | — | 1 PC. | 230 | |
| — | — | — | 1 PC. | 260 | |
| Styrofoam shells | — | — | Internal - 110 | 1 PC. | 609 |
| — | — | 1 PC. | 515 | ||
| — | — | 1 PC. | 429 | ||
| Expanded clay of different fractions | — | — | — | 45 cubic meters | 1300 |
| 50 cubic meters | 1650 | ||||
| 60 cubic meters | |||||
| 65 cubic meters | |||||
| 70 cubic meters |
heating cable prices
This is not to say that the prices for heating cable are low. For one linear meter, perhaps the price may seem low, and such a cable can be bought if you only need to heat small plot sewer pipes.
However, in the case of heating the entire external sewage system, you will have to fork out a lot to purchase required amount meters of electrical cable.
And, nevertheless, some owners of an external sewer pipeline passing above the ground or lying on the ground prefer to invest once in order to use the sewer later without much hassle.
So, for example, the cost of a self-regulating cable varies depending on the power consumption.
| Product Name | Power consumption on the coil, W/m | Price, rub |
| Self-Regulating Heating Cable - Unshielded | 16 | 115 |
| Self-Regulating Heating Cable - Shielded | 16 | 260 |
| Self-regulating heating cable - shielded in conduit | 15 | 320 |
| Self-regulating heating cable | 24 | 280 |
| 30 | 290 | |
| 40 | 450 | |
| 80 | 680 |
Resistive tapes or cables also differ in specific or rated power, length and weight, which is why their prices also differ from each other.
| Name of product | Specific power of electrical tape, W/m | Rated power of electrical tape, W | Length, m | Weight, kg | Price for 1 piece, rub., 250C | Price for 1 piece, rub., 180С |
| Resistive tape ENGL 1 | 100 | 260 | 2,61 | 0,51 | 710 | 640 |
| 80 | 230 | 2,92 | 0,55 | 770 | 700 | |
| 30 | 140 | 4,80 | 0,75 | 1090 | 990 | |
| 15 | 100 | 6,80 | 1 | 1630 | 1480 | |
| Resistive tape ENGL 2 | 40 | 160 | 4,12 | 0,50 | 470 | 470 |
| 30 | 140 | 4,80 | 0,60 | 555 | 555 | |
| 40 | 330 | 8,24 | 0,90 | 945 | 945 | |
| 30 | 580 | 19,21 | 2 | 1720 | 1720 | |
| 40 | 1310 | 38,41 | 3,80 | 2600 | 2600 |
The need for insulation of sewer pipes is obvious. And it doesn't matter where they pass or lie: underground, on the ground, above the ground or in an unheated basement.
Important! It is very important to choose best options heat-insulating materials, make sure or decide whether it is really necessary to heat the sewer pipes with an electric cable.
Because with improper preparation and calculations, you can make a mistake and incorrectly insulate this or that pipe, which can still freeze in winter, despite the thermal insulation. Therefore, select options and methods of thermal insulation carefully and thoughtfully.
Sewerage is an integral element of almost any building and structure. Proper care behind the drainage system is the key to its long and uninterrupted operation, and it is especially important to correctly organize the insulation of sewer pipes. In the cold season, this will avoid the failure of the pipeline due to its rupture or the appearance of ice jams in it.
Our article will tell about the materials and methods of insulation of sewer pipes.
The need for thermal insulation
Do sewer lines need to be insulated? This question can be answered in two ways, since everything will depend on the climatic zone where the development takes place, and on the construction technology. Of course, if the building is located in an area where the temperature rarely drops to minus levels, then this is not necessary. If frosts are fierce in the climatic zone of the localization of the building, then this procedure will be necessary.
You can not insulate even if the communication is laid at the right angle and is located below the freezing layer. Thermal insulation of pipes of the drainage system will be required in the following cases:
- the pipeline has turns;
- laying depth does not exceed 0.5 m;
- with a slight slope (less than 0.5 cm per linear meter);
- with a large pipe slope (more than 1.5 cm per linear meter);
- with frequent blockages.
Materials for insulation
The modern market offers a variety of materials for insulation of sewer pipes. Consider which of them are used more often than others:
- Glass wool. Previously, it was almost the only material for insulating pipes in the ground. But now it is used very rarely, because. requires additional use of waterproofing, and the effectiveness of such insulation is not high enough.
- Basalt insulation. It has a high degree insulation and easy installation. The disadvantage is the high price.
- Styrofoam. It is in our time the most popular heat-insulating material, which is explained by a combination of budget prices, good operational qualities and easy to install.
- Polyurethane foam, like expanded polystyrene, retains heat quite well, and it is produced in the form of a shell that covers pipes. Sometimes sewer pipes are already insulated, i.e. are initially in a shell of this material. This fact greatly facilitates and speeds up the installation of an external sewage system.
- Penoizol. Thermal insulation technology using penoizol allows you to completely isolate the pipeline system from both low temperatures and moisture in the soil. It is performed using special equipment, where penoizol is presented in liquid form.
- Foamed polyethylene. It is a widely used insulator. With it, you can quickly and efficiently insulate pipes at home with your own hands.
How to protect sewer pipes from freezing
There are 3 ways by which you can eliminate the formation of ice blockages in the outer part of the sewer system:
- engineering;
- with the help of a heater;
- active.
engineering method
The engineering way is the most simple solution the question of how to insulate sewer pipes on the street. It consists in the following - the pipes are simply laid below the level of soil freezing. As practice shows, for this they sometimes have to be laid to a depth of 2 m or more. For each region, depending on the climate, the depth of the bookmark will be different. Implement this method as follows:
- At a given depth, they dig a trench under the drain pipeline with a slope of 1 cm per meter of its length. The depth can be found in a special table for each region.
- At the bottom of the dug trench, a sand cushion or a cushion of fine gravel (grain size no more than 20 mm) is made, at least 10 cm thick.
- Lay pipes.
- Cover them with a layer of sand or fine gravel. The layer should be located above the pipe at a height of at least 20 cm and be carefully compacted.
- Fill the trench with previously excavated soil.
Thermal insulation method
What insulation to use - indicated above. The choice of material depends on many factors, among which, first of all, one should highlight the cost and thermal insulation properties.
So, let's consider how to properly insulate a sewer pipe. Installation of outdoor drain system using heat-insulating material should be performed in the following sequence:
- The place where the trench will pass is marked.
- A trench is dug, while its width should be at least 60 cm, and the depth should correspond to the project data with a margin of 5-10 cm. The trench is equipped with a mandatory slope (1 cm per 1 linear meter) to ensure gravity flow.
- At the bottom of the trench, sand or gravel with a thickness of at least 10 cm is poured and rammed.
- The pipeline is assembled on the surface next to the trench.
- The seal and the edge of the pipe must be lubricated with sealant.
- The insulation is put on the pipe and fixed (usually with adhesive tape) so that it does not move.
- The pipe is lowered into a trench, covered with a layer of sand or gravel, after which it is rammed.
- Next, the trench is finally covered with soil, while making sure that it does not contain stones, broken glass or hard ground.
Internal sewerage, as a rule, is not insulated. Only the exit of the riser to the roof of the house is subject to thermal insulation, since with a sharp temperature drop it can simply burst. The material for insulation of the riser can also be either mineral wool or expanded polystyrene.
active way
The most costly way of thermal insulation is the so-called active insulation. It consists in laying electric heating cables along pipes. These cables, when heated, give off heat to the pipeline and prevent it from freezing. The heating system is controlled by a temperature sensor with automation connected to it. As soon as the temperature around the external sewer system approaches zero, the sensor is triggered and the cable heats up the pipeline. When the ground temperature rises, the system automatically turns off.
Applying active insulation in practice, you will also need to arrange an insulation system, because. the heating cable will heat the ground, not the pipes. This method is quite costly both during implementation and during operation, and not everyone can afford it.
How to insulate a drain pipe facing the street? The simplest and cheapest method is a foam shell, which will insulate it well. In everyday life, glass wool is more often used, which is simply wrapped around the drain pipe and tied with tape.
Insulated outdoor sewer pipes will last longer if one of the thermal insulation methods described above is introduced. In addition, when laying the system, it is recommended to use smooth pipes made of polyvinyl chloride and polypropylene with an orange surface.
At your discretion. To get effluents into it, a pipeline is laid from the outside. Uninterrupted work systems can be provided by insulating the sewer pipe. Getting started, it is important to familiarize yourself with the advice of specialists who give general idea how to insulate a sewer pipe correctly.
The article does not refer to sewer pipes laid in heated rooms or below the level of soil freezing. We will talk about those cases when insulation is indispensable. In the apartment, pipe insulation improves sound insulation.
The consequences of freezing pipes
Frozen pipes are quite common. The problem is especially familiar to residents of houses with local sewage.
- Freezing in pipes, water stops the entire system. Drains cannot move into the septic tank, as there is an ice plug in their way.
- Frozen water can cause severe pipe damage. In the process of freezing, it expands and destroys the pipe, which subsequently leads to repairs that are problematic to perform in winter, especially when above the pipe large layer frozen soil.
Why is it needed
Some sources believe that the insulation of the sewer pipe in the house is not necessary, since the drains, moving through the pipe, have room temperature. In addition, the liquid is constantly moving in the pipes, draining into the septic tank. But freezing happens, and it will not be easy to fix the breakdown. In some cases, repairs are postponed until warm weather, and the house is left without sewerage.
Going to an outdoor restroom has some benefits:
- Going to the toilet takes much less time.
- Great water savings in winter, since the toilet does not need to be flushed, but you will have to wash in a bowl or in a public bath.
True, such a prospect of “savings” will please few people, therefore, in order to minimize the risk of similar situations, it is better to start insulating the system in advance.
The most popular are three methods of insulation of the sewer system:
- With heaters.
- Laying the heating cable.
- The pipe is placed at a depth that is below the freezing level of the soil.
Types of materials
For insulation of external sewerage, various heat-insulating materials can be used.
Mineral wool
The material belongs to classic version. But in the process of work, its use is not profitable for economic reasons. When using mineral wool, an additional layer of waterproofing is required, since the material is hygroscopic and, when moistened, loses its main function.
Polyurethane foam and foam
The material should be used for external insulation, as it does not tolerate moisture testing. It is produced in the form of cylinders cut along, with a recess for pipes. The fastening of the cylinder occurs due to the locks located on the edges. The material is extremely comfortable to work with, retains heat well and is inexpensive.
Foamed polyethylene
An easy-to-use material that is produced in the form of pipes. If necessary, put it on desired area, pre-cutting the material. The incision site is sealed with tape.
Work with a pipe in the ground
There are also several ways to insulate pipes in the ground.
Penoizol
This insulation is produced in the form of a liquid agent, which, when solidified, forms a dense shell that prevents the pipe from freezing.
Among the disadvantages of the material: in the process of work, it is necessary to use special equipment. Therefore, its use for insulation in a private house will be expensive.
Using a heating cable
A modern method of pipe insulation is a heating cable, which is laid over or inside the pipe. During operation, laying is carried out in a protective channel.
By giving preference to this method, it is possible to lay the pipe to a depth of less than half a meter.
The disadvantage of this method is the dependence of the system on electricity. When the electric heating is turned off, it stops working.
It should be noted that there is a conventional type of cable and self-regulating.
- The first type will be cheaper, but energy consumption will be uneconomical.
- The second version of the cable heats only the area of the pipe with a low temperature.
It is better to buy a more expensive version of the heating cable, which will pay off later due to energy savings.
The most popular method of insulating a sewer pipe in the ground is its location at a depth below the freezing level of the soil, where the temperature remains positive and does not allow the pipe to freeze. This method does not require special insulation.
- On the preparatory stage they dig trenches, the width of which reaches 60 cm. At the same time, the diameter of the pipe is 110 mm. The depth of the trench should be slightly higher than planned (about 10 cm). It is important to stick to a slope of 1%.
- Exceeding the depth by 10 cm is necessary for laying a sand cushion, which is poured onto the bottom and rammed.
- The next step is to lay out the pipes and necessary elements connecting the system.
- Perform the connection of all parts.
- You can put a heater on the pipe and fix it with special tape so that the material does not hang out.
- The system must be covered with sand and tamped on the sides of the trench. It is not necessary to compact the sand above the pipe, in order to avoid damage to the pipe.
- On the final stage the trench is covered with earth. In this case, you need to make a small hill above it, as the earth will sag and the surface will level out.
Among the disadvantages of this method, it is necessary to highlight the lack of the possibility of repair in case of blockages or other pipe breakdowns. It will be necessary to break the system, which in winter will be very problematic to do.
outdoor work
Most suitable option insulation of a sewer pipe on a street in a region with severe frosts is a combined method. If winters are not characterized by low temperatures, you can give preference to insulation with heat-insulating material without using a heating cable.
- When laying the pipe, it is important to observe the slope. The smaller it is, the more reliable the material for insulation should be.
- For work, a foam shell is useful, with the help of which the already assembled system is insulated.
- In conclusion, the shell must be fixed with aluminum tape.
- The areas where the pipe is connected to the surface are insulated with a heating cable (preferably self-regulating).
Insulation of a sewer pipe is not an obligatory event, but it is desirable, during which a little money and patience will be required. As a result, the owners will be protected from unexpected surprises in the midst of frost.
Video
In this video, you will be introduced to the features of competent insulation of sewer pipes: