Preface. How and with what to insulate a columnar foundation of a house with your own hands? Is it necessary to insulate the columnar foundation of a bathhouse and a house? Proper insulation of foundation pillars will help conserve heat and protect the structure from early destruction. In the article we will look at how to insulate a structure yourself, what materials to use for thermal insulation, and also show a video on this topic at the end of the article.

Columnar foundation wooden house used on complex and heaving soils. Pillars are placed in the corners of the house and at intersections interior walls, as well as along the perimeter of the building after 1.5–2.5 meters and below the depth of soil freezing on the site. The pillars usually rise above the ground by 0.25-1 meters. To make the structure rigid, a strip foundation is poured along the top of the pillars or strapping beams are placed.

Is it necessary to insulate the columnar foundation of a house?

Photo. Diagram of a pillar foundation

If the columnar foundation of a wooden house is made of rubble or concrete, then after removing the formwork, the surface of the pillars is insulated with bitumen mastic in two layers. Instead of bitumen, you can use penetrating waterproofing Penetron, which penetrates deeply into the micropores of concrete. It is also necessary to treat and independently insulate the strip foundation or strapping beams from moisture rising from the ground.

Independent insulation of the columnar foundation of a house from the outside is carried out using extruded polystyrene foam (penoplex or technoplex). You can also use a cheaper, but less durable board material - polystyrene foam. To choose the right materials for thermal insulation, you need to consider the most popular slab insulation materials, specifications polystyrene foam and penoplex.

How to insulate a columnar foundation of a house from the outside

Photo. Insulation between the soil and the wall of the house

Styrofoam Suitable for both external and internal insulation of columnar foundations of bathhouses and houses. Many developers choose expanded polystyrene due to its low cost, but better foam replace with more durable extruded polystyrene foam. Penoplex is a more expensive material, but has high mechanical strength; thermal insulation boards are not afraid of high humidity and rodents, which is an advantage.

Penoplex, like other extruded styrene (technoplex, ursa xps, etc.) is characterized by high strength, low vapor permeability and durability. The insulation is produced in slabs with a thickness of 20 to 100 mm; the material is resistant to humidity and does not harbor microorganisms, insects and rodents. Penoplex is used today not only for thermal insulation of the foundation, but also for insulating the blind area of ​​the house around the perimeter.

Mineral wool, like basalt wool, is supplied in rolls and slabs of various thicknesses. Despite the low thermal conductivity of URSA mineral wool, like mineral thermal insulation other manufacturers have high water absorption. The use of mineral wool as thermal insulation for house foundations is not recommended. The material should be carefully protected from moisture; find out which side to lay the vapor barrier on mineral wool on our website so as not to make mistakes when carrying out waterproofing.

Expanded clay is an inexpensive insulation material for columnar foundations and is a time-tested material. Developers use expanded clay for thermal insulation of the pillar foundation of a house or bathhouse as follows: with inside For the foundation, formwork is erected from 30-40 cm boards and expanded clay is poured into it. You can also fill the foundation inside the house with soil or the same expanded clay.

Scheme of insulation of a pillar foundation of a house

Independent thermal insulation of a columnar foundation with polystyrene foam or technoplex is similar to insulation screw foundation, since the designs are largely similar. All work is carried out immediately after waterproofing the structure, covering the grillage (banding beams) and part of the facade of the house by 25–0 cm. The foundation pillars are sheathed with bars and boards to the full depth to create a frame for thermal insulation.

How to insulate a columnar foundation with your own hands

How to insulate a columnar foundation of a house from the outside? To insulate a columnar foundation with penoplex, the sheets are secured with dowels or attached with polystyrene foam glue to the prepared base sheathing. Penoplex is durable, has high mechanical strength and retains its properties in wet soil. The seams between the thermal insulation boards are carefully sealed with polyurethane foam.

If there is no base between the foundation pillars, then only the grillage is insulated (insulation wooden floor below), and moisture-resistant slab insulation is laid on the ground inside the house. This work can be done independently; for this purpose, an insulated floor is installed from mineral wool, a similar technology is used when insulating the floor in an apartment on the first floor or the basement of a private house.

Video. How to insulate a columnar foundation from the outside

Preface. Is it necessary to insulate the columnar foundation of a house? We will definitely say what is needed. Proper insulation of a pillar foundation with your own hands will help save heat, which means money for heating the house. In this article we will look at diagrams for self-insulation, materials for insulating a pillar foundation, and also show a video, how to insulate a columnar foundation with your own hands.

A columnar foundation consists of pillars of wood, concrete, brick or rubble. The pillars are placed below the freezing depth of the soil. The pillars run along the entire perimeter of the building every 1.5 - 2.5 m. They must be placed in the corners and places where internal walls intersect. The pillars usually rise from the ground by 0.25-1 m. At the upper ends, for structural rigidity, a reinforced strip foundation is poured or strapping beams are placed.

Types of columnar foundations

If the columnar foundation is made of rubble or concrete, then after stripping the outer surface of the pillars, they are independently waterproofed with bitumen in two layers with a roofing felt pad. Instead of bitumen, it is better to use penetrating waterproofing, for example, Penetron. It is also necessary to treat the strip foundation or grillage (tied beams) from increased soil moisture.

How to insulate a columnar foundation of a house

Insulation of a columnar foundation is often done using extruded polystyrene foam ( trademark– Penoplex). Also, when insulating, foaming polyurethane foam is sprayed. In order to choose the right insulation for a pillar foundation, it is necessary to briefly consider the main types of insulation, their technical and thermal insulation characteristics.

Styrofoam It is more suitable for internal insulation of pillar foundations, but many, due to the low cost of the material, use it for external thermal insulation of foundations. But it is better to replace polystyrene foam with insulation materials that have higher strength and are not afraid of increased humidity from the ground.

Expanded clay It is also an inexpensive insulation for pillar foundations; developers use it following method: on the inside of the columnar foundation, formwork is made from boards and covered with expanded clay to a depth of 30-40 cm.

Mineral wool, like polystyrene foam, is used to insulate a columnar foundation from the inside; mineral wool is supplied in rolls and slabs. It has high water absorption and compressibility. Therefore, when using it, the insulation should be carefully protected from moisture with a vapor barrier.

Penoplex is characterized by high strength and durability. The insulation is not afraid of moisture, rodents do not grow in it. Penoplex is used not only for insulating the columnar foundation, but also for insulating the blind area of ​​the house around the perimeter, insulating strip foundation, is produced in slabs with a thickness of 20 – 100 mm.

Thermal insulation of a columnar foundation with foam plastic or other insulation is done immediately after waterproofing is completed, covering the grillage and part of the wall of the house by 25 - 40 cm. When insulating the foundation from the outside, it is plastered with cement-sand mortar or mixtures; this procedure can be done with your own hands, since this is not requires special skill and extensive experience in construction.

Do-it-yourself insulation scheme for a columnar foundation

The pillars of a columnar foundation are sheathed with bars or boards to the full depth. It is necessary to make a non-load-bearing base; the insulation scheme is similar to the insulation of a screw foundation with mineral wool, since their design is in many ways similar. Insulation (expanded polystyrene, resistant to humidity and mechanical damage) about 400 - 500 mm wide is laid on the backfill to cover the cold coming from the ground.

If there is no base between the pillars, then only the grillage from below is fully insulated. It is difficult to install such a system yourself, so it is easier to make an insulated three-layer mineral wool floor on the ground floor with a thick thermal insulation layer; a similar method is used by builders when insulating the basement of a house or cesspool with your own hands.

How to insulate a columnar foundation of a house

To insulate a columnar foundation with expanded polystyrene, the sheets are secured with dowels with fungus or glued to the base using adhesives. Penoplex is frost-resistant, moisture-resistant, with high mechanical strength, environmentally friendly, retains its properties in wet soil and guarantees insulation of the foundation for many years

Penoplex seams are sealed with foam or sheets with an edge are used. Externally, polystyrene foam is protected from solar ultraviolet radiation with cement plaster or PVC panels. To prevent moisture and water from rising from the ground, the base and soil under the house are covered with a layer of waterproofing. Next we will show the video, how to insulate a columnar foundation with penoplex with your own hands.

How to insulate a columnar foundation. Video lesson

In order for the house to have a comfortable and warm environment, it is necessary at the construction stage, namely when laying the foundation, to take care of its thermal insulation.

Although insulating a columnar foundation will take time and money, its thermal insulation will keep the house warm, which means it will save on heating costs.

Insulating the foundation is a mandatory measure that helps keep the house warm. If you neglect such a work process during the construction of the foundation as thermal insulation, the house will lose ten percent of all heat loss. It is better to invest once in insulating the foundation than to overpay for heating. If, then this will protect in the future from heaving and freezing of the soil, which avoids deformation of the foundation, and also prevents the appearance of dampness and mold. Insulating a columnar foundation will cause some difficulties, but if you approach this matter competently, the result will certainly exceed all expectations. The insulation process begins with the selection of insulation material; for this you need to know its basic properties.

How to choose insulation

Extruded polystyrene foam. Its main properties are determined by the following criteria: frost resistance, high mechanical strength, long-term insulation, moisture resistance, long service life, environmentally friendly and resistant to biological influences. Expanded polystyrene is usually used for insulating strip and monolithic foundation, and it can also be used to insulate roofs, floors and walls of a house.

Polyurethane foam has the following characteristics: resistance to chemical attack, good adhesion to the foundation, has no seams, retains its properties in wet soil, has waterproofing properties, suppresses noise, guarantees insulation of the base for many years, does not require additional work on hydro- and vapor barrier. But to use such insulation, you need special equipment and a specialist to carry out this work.

Polystyrene foam is afraid of moisture and is more suitable for internal insulation, but some use it for external insulation due to the low cost of such material, while providing decent insulation. But it is better to replace polystyrene foam with its varieties, which have high strength and reliability.

Expanded clay is also an inexpensive insulation material; it is used using the following method: formwork is made on the inside of the foundation and covered with 30-40 cm of expanded clay.

Mineral wool is used to insulate the foundation from the inside; it is supplied in rolls or slabs. It has properties such as high water absorption and high compressibility.

Penoplex is characterized by high strength, reliability and durability; it is used to insulate columnar foundations and is produced in the form of slabs with a thickness of 20 to 100 mm.

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Insulation as a method of insulating a columnar foundation

The best option for insulating a columnar foundation is a fence, because... a columnar foundation consists of columns and a grillage, and the space from the grillage to the ground surface remains open. A fence is a structure that organizes the basement space for a columnar and pile foundation and provides insulation. When used, the space between adjacent pillars and the space between the base of the house and the ground surface are blocked, thereby forming an underground room. It will protect the house from weathering in cold weather and keep the house warm. The pick-up is made from various materials: wood, stone, reinforced concrete, brick and others, which will be responsible for insulation.

Let's consider the technology for constructing a fence for a columnar foundation made of wood, which, in turn, is divided into types depending on the method of placing the boards. You can place the boards vertically or horizontally, or make a fence from beams or logs.

Based on the chosen type of pick-up, the following building material will be required:

• sand;
• gravel;
• boards;
• nails;
• roofing felt;
• cement;
• penoplex 60x120 cm, thickness 100 mm;
• glue;
• polyurethane foam;
• finishing (optional);
• bitumen or bitumen mastic;
• reinforced mesh.

Tools required for work:

Image 1. Scheme of collection at vertical mounting boards

• shovel;
• hammer;
• Master OK.

When fastening boards vertically (image 1), use the following operating algorithm:

1. It is necessary to dig a trench between the pillars 20-40 cm deep (it must correspond to the freezing depth).
2. Sand and gravel must be poured into the trench so that this cushion occupies a third of the trench.
3. You need to place a log with a groove in the trench on the cushion and secure the same log to the grillage.
4. In the grooves between the logs you need to strengthen the boards in a vertical position.

With the horizontal method of laying boards, work is carried out as follows:

1. Dig a trench between the pillars 20-40 cm deep.
2. Make a bed of sand and gravel.
3. Attach the logs with grooves to the posts.
4. Boards 4-6 cm thick are laid in the grooves of the logs, the first board will thus rest against the trench cushion.

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Insulation with wooden boards

Image 2. Scheme of fastening logs between foundation pillars.

To insulate a fence made from wooden boards, expanded clay is added to its inner side, which will serve as insulation.

Before starting the harvesting process, it is necessary to treat the wood with antiseptic substances and impregnations, which will protect it from destruction.

The third method of making a fence from logs is characterized by the following stages of work: between the foundation pillars, the logs need to be strengthened in the same way as during the construction of a log house (image 2).

After making the wooden fence, you can begin the insulation process itself. Extruded polystyrene foam or penoplex can be used as insulation material; these types do not require mandatory waterproofing. But if you have additional strength and capabilities, then it is better to waterproof the foundation. In this case, penoplex is used, this best option for insulation of columnar foundations.

So, the first stage is waterproofing. Bitumen (or bitumen mastic) is applied to the intake, starting from its upper part. Next, strips of roofing felt are applied; they must be pressed and leveled over the surface.

The second stage is gluing the penoplex. But first you need to calculate how thick the foam sheet should be in order to properly insulate the foundation. Each region has its own value, it is calculated using the following formula:

R = (H1 / λ1) / (H2 / λ2)

R is the heat transfer resistance for a specific region. For Moscow and the Moscow region it is equal to 3.2 m²×°K/W;

λ1 is the thermal conductivity coefficient of the foundation material;

H2 - thickness of the insulation material (Penoplex);

λ2 is the thermal conductivity coefficient of Penoplex.

You need to decide on the number of penoplex slabs based on one slab, which is equal to 0.72 m².

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Description of work

Image 3. Scheme of foundation insulation with Penoplex.

In the prepared trench from the bottom corner you need to glue a layer of penoplex onto the waterproofing layer using special glue. The glue is applied pointwise to the foundation waterproofing in 5-6 places, after which you need to wait a minute and fix the slab with glue. Additional fastenings are not necessary, otherwise the waterproofing layer may be damaged. The slabs must run smoothly end to end, without any gaps. There are foam boards on sale that come with locks, which makes the joining process easier. You can use two layers of insulation, using XPS 50 mm thick slabs instead of 100 mm XPS, then the second layer of penoplex will cover the joints and thereby close the completely formed gaps. If you decide to insulate the foundation in one layer, then you can seal the cracks using polyurethane foam.

Then you need to level the glued slabs; to do this, you need to strengthen the reinforced mesh on top of the penoplex and perform classic leveling using a cement-sand mixture.

The third stage is the installation of a blind area. The trench needs to be filled with expanded clay or earth, this will be a reliable support for the insulation. Some experts advise isolating the insulation from contact with the ground with roofing felt, this should increase the service life of the insulation. The surface of the earth needs to be compacted, leveled, foam polystyrene reinforced on the surface and a blind area made with an asphalt or concrete strip around the house (image 3). Penoplex slabs should protrude at least 40 cm above the ground surface, this helps to avoid moisture from rain and melt water.

The fourth stage is finishing the insulated foundation. The finishing material here can be decorative rock, facing brick or siding panels. The finishing will be the individual choice of the owner. On this issue, it is better to contact specialists who will advise you and tell you which finish is better.

A fence made of brick or stone is constructed as follows. First you need to prepare the base for the brick, namely, make a concrete screed. To do this, you need to dig a trench up to 50 cm deep, make a cushion of sand and gravel, lay reinforced rods and build formwork. Concrete is then poured into this structure. After the concrete has hardened, you can begin laying bricks, which is done in 1-1.5 bricks; it should be at least 50 cm in height, since the higher the brickwork, the warmer it will be in the house.

If the height of the pillars reaches 0.7 m or more, then in this case building material A thermal insulation sheet will serve as a pick-up. To do this, a device in the form of a steel frame is attached to the foundation pillars. Next, a thermal insulation material is attached to the inside - either polystyrene foam or polystyrene foam. On the outside, corrugated sheeting is attached to self-tapping screws. In this case, it is imperative to seal the gaps that have formed between the ground and the corrugated sheets with heat-insulating material.

When constructing a fence, it is necessary to make ventilation windows with a diameter of 10-15 cm on opposite walls, and on winter period cover them with plugs.

First steps:

• Check with the geological exploration service about the depth of soil freezing in the given region. The foundation is insulated up to this mark;
• choose the insulation method: outside or inside;
• clarify the pros and cons of various insulation materials;
• before installing the heat-insulating layer on the outside of the building, carry out additional work;
• creating fences will close the gaps between the foundation pillars and prevent various precipitation from getting inside;
• Before installing external thermal insulation, check whether the base needs waterproofing.

Insulation of the foundation from the outside

Most builders believe that thermal insulation from the outside is preferable to insulating the base from the inside. Weighty arguments:

• the thermal insulation layer on the outside maintains the strength of concrete;
• regardless of the type of foundation and insulation, the cold does not penetrate inside the house;
• insulation on the outside of the foundation provides reliable protection from moisture;
• temperature fluctuations are well “damped” by the outer thermal insulation layer.

Internal foundation insulation

This method is used quite rarely. The thermal insulation layer inside has more negative sides than advantages. Study them.

Advantages:

• thermal insulation inside protects the basement walls from condensation;
• there will be a comfortable microclimate in the basement and in the house.

Flaws much more serious:

• the foundation from the outside is defenseless against the effects of low temperatures;
• Temperature changes and soil heaving quickly lead to deformation and the appearance of cracks in the foundation.

Materials for foundation insulation

Thermal insulation layer can be done from:

• penoplex;
• polystyrene foam;
• polyurethane foam;
• extruded polystyrene foam.

When choosing insulation Please note the following characteristics:

• coefficient of thermal conductivity. The lower it is, the better material keeps warm;
• density. This factor influences the size of the load on the foundation;
• flammability of the material. A high flammability class (G1) will provide reliable protection against fire;
• water absorption coefficient. The worse the material absorbs moisture, the fewer problems with dampness and mold on a damp base.

Do-it-yourself insulation of a columnar foundation

Have you decided to insulate the base yourself? How to insulate a columnar foundation yourself? To do this, follow the steps below.

Note! The process of insulating the foundation of a brick and wooden house is carried out using the same technology.

Pickup device

The fence protects the foundation from atmospheric precipitation. It acts as a base. High-quality insulation The fence will help rid the house of drafts, provide a good microclimate and the absence of dampness.

Procedure:

• between the pillars, dig a trench with a depth of 20 to 40 cm;
• add gravel and sand 1/3 of the way;
• secure the beams with grooves for installing boards;
• with the vertical method of fastening the beams, one part is fastened in the trench, the other in the lower part of the house;
• when the bars are placed horizontally, they are attached directly to the posts;
• insert boards 4 to 6 cm thick into the grooves of the beams and secure them well;
• sprinkle expanded clay on the inside of the finished pick-up;
• Now you can move on to installing the thermal insulation layer.

Foam plastic for base insulation

Any home craftsman can handle this type of work.:

• thoroughly clean the surface intended for insulation;
• seal all cracks and eliminate irregularities;
• start working from the bottom up;
• Apply suitable adhesive to the foam boards;
• glue the sheets to the base and secure with special plastic dowels;
• the next layer is reinforcing mesh;
• next – putty;
• The last layer is finishing putty.

Insulation with extruded polystyrene foam

This material is often used to construct a thermal insulation layer. Expanded polystyrene prevents the appearance of dampness and the development of fungi. Retains heat well. The sheets are easy to install using a special adhesive composition.

Installation is carried out without any difficulties:

• the first layer is waterproofing;
• start attaching expanded polystyrene slabs from the bottom, moving upward;
• if the waterproofing is made of bitumen roll material, just heat the bitumen to 55 degrees, apply the slab and press well;
• with other types of waterproofing substrate, the insulation is secured with a special mastic. It is applied to polystyrene foam in the form of strips;
• Place the slabs against the waterproofing and press.

Thermal insulation of the foundation with polyurethane foam

A new word in construction practice. The material quickly gained popularity.

A durable, environmentally friendly, durable, fireproof polymer is applied from a special blowing machine. Just 5cm of polyurethane foam - and your foundation is well insulated. An undoubted advantage is the high speed of work.

If you can rent a blowing machine - do the work yourself:

• clean the foundation from dust, debris, and earth particles;
• Apply the insulation directly to the base. The foam will fill all the cracks and irregularities. No voids or air pockets;
• adhesion is excellent. The material sets quickly;
• the result is a high-strength synthetic board.

Note! The material does not absorb moisture. For reliability, experts recommend additionally adding waterproofing from a water-repellent material on top of the insulation layer: liquid rubber, polyurea and others.

If nothing works out with renting a machine for applying polyurethane foam, you will have to call specialists from a construction company.

Insulation of the foundation with penoplex

Penoplex is made using a special technology from extruded polystyrene foam. The material has excellent performance:

• one of the most heat-resistant polymers;
• durable;
• durable;
• safe for humans;
• installation is quick and easy;
• A wide range of polymer boards (thickness from 20 to 100mm) allows you to choose the right option and not overpay for the extra layer thickness.

Slab size: 60x240 and 60x120mm. There are three categories of insulation with different densities.

Note! The polymer is quite flammable. Perhaps this is its only drawback. You can apply a layer of fire retardant. At the same time, environmental indicators will decrease.

Procedure:

• cover the entire surface with a special adhesive mastic: from the sole to the grillage;
• to the zero level, simply press the slabs against the wall;
• between the zero level and the grillage, additionally secure the penoplex with umbrella dowels;
• to attach heat-resistant dowels, drill holes in the base;
• Most panels fit well into the groove. Check all seams. To be sure, insulate them with polyurethane foam.

Insulate the columnar foundation using technology appropriate for each type of thermal insulation material. High-quality insulated base will serve as the basis for warmth and a comfortable microclimate throughout the house.

One of the final stages of finishing an already constructed building is the thermal insulation of its foundation, since this ensures comfortable conditions in the house. In solid foundations, the issue of their thermal insulation is easily resolved, but in columnar foundations, this causes additional problems and work.

Insulation of a columnar foundation with a pick-up device is the most in a simple way solutions to this problem. What is pick-up and how it is done, we will consider below.

Types of fences for insulating a columnar foundation

The fence is one of the options for the base, which is an accessory to columnar foundations and performs the function of protecting the space between the building and the ground from rain, snow and wind.

They are used for picking up the most different materials, affecting its structural design and construction technology. Let's decide on all these parameters for each specific option:

Wooden pick-ups. This option, in turn, has several subtypes, namely: made from boards, with vertical or horizontal installation of the latter, and made from logs or timber.

When making a fence with horizontal boards, installation is performed as follows:

• a trench 200-400 mm deep is dug between the pillars;
• sand and fine gravel are poured to approximately one-third of the depth;
• bars or logs with a groove are attached to the posts;
• boards 40-60 mm thick are inserted into the grooves, with the bottom board resting on a cushion in the trench;
• then the lower part, from the inside, is covered with expanded clay or other heat-insulating backfill.

When installing boards vertically in a recess, a log with a groove is placed in a trench made according to the previous option, a second, identical log is attached to the bottom of the building, after which the boards are vertically inserted into the grooves.

In some cases, logs are laid horizontally between the pillars, similar to the construction of a log house.

Fences made by masonry of brick, stone, etc. In the case of constructing a fence from these materials, a trench with a cushion is also required, which is the base for its walls. When made from stone, the thickness of the wall is made within 300 mm; from brick, it is placed in 1-1.5 bricks.

The fences are insulated with heat-insulating sheets. In buildings installed on high poles (from 0.7 m and above), insulation of the underground space is carried out in this way:

• a frame structure made of steel profiles of various sections is attached to the posts;
• from the inside, sheets of polystyrene foam, expanded polystyrene or other heat-insulating material are hung on the frame;
• from the outside, with self-tapping screws, corrugated sheets are attached;
• the gap between the corrugated sheets and the ground, on the inside, is covered with heat-insulating material.

For all options for making a fence, ventilation holes must be left in the opposite walls, 100-150 mm in diameter is sufficient. For the winter, these holes are closed with plugs.

Which of the presented options for insulating a columnar foundation is better and which one to choose can only be decided by the home owner himself.

Insulation of a columnar foundation - insulation technology