How to insulate the basement of a house outside: step-by-step instructions for the selection and installation of thermal insulation

Thermal insulation should be comprehensive, and if wall insulation is performed, the roofing system and foundation cannot be ignored. One of the most vulnerable areas is the basement part of the house, through which up to 20% of the heat escapes. You can protect the basement from moisture and freezing both at the construction stage and during the operation of the building, the main thing is to choose the right materials for this.

How to insulate the basement of a house outside: step-by-step instructions for the selection and installation of thermal insulation

How to insulate the basement of the house outside

Requirements for the basement insulation

The basement is is a part of the foundation located above the ground level. From below, it is constantly in contact with damp and frozen soil, and the side walls are exposed to precipitation and sudden temperature changes.

All this leads to an increase in the cost of heating the interior, the appearance of dampness and mold in the house, and a decrease in comfort for household members. In addition, the materials from which the basement is erected wear out faster, cracks and cracks form in the walls, and here you cannot do without major repairs.

How to insulate the basement of a house outside: step-by-step instructions for the selection and installation of thermal insulation

A typical example of the destruction of an uninsulated basement

When the basement is insulated, the cold bridges overlap, the outer walls receive protection not only from water and freezing, but also from mechanical damage, the structure lasts longer and does not require repair.

How to insulate the basement of a house outside: step-by-step instructions for the selection and installation of thermal insulation

It is important to properly insulate the base

But this is only if the heaters fully meet the following requirements:

  • minimum thermal conductivity;
  • zero water absorption;
  • high compressive strength;
  • resistance to microorganisms.

Not the least important is the durability of the insulation, because the longer the service life of the material, the less often it will have to change and repair the base.

As for the composition of the insulation, especially its environmental safety, there are no strict requirements, because the material will be on the outside of the building, between the layers of waterproofing and decorative coating.

How to insulate the basement of a house outside: step-by-step instructions for the selection and installation of thermal insulation

Table of the effectiveness of the use of insulation

How to insulate the basement of a house outside: step-by-step instructions for the selection and installation of thermal insulation

Comparison of heaters and various materials

The choice of insulation for the basement

Among the wide variety of modern heaters, the above requirements are fully met only by polymer-based plate and spray materials. Let's consider their characteristics in more detail.

Foamed polystyrene foam

How to insulate the basement of a house outside: step-by-step instructions for the selection and installation of thermal insulation

Foamed polystyrene foam

How to insulate the basement of a house outside: step-by-step instructions for the selection and installation of thermal insulation

Insulation with expanded polystyrene

Expanded polystyrene (polystyrene) has been used as insulation for a long time, and still does not give up its positions. It retains heat excellently, does not accumulate moisture, is easy to cut and is lightweight for effortless installation.

In addition, polystyrene has the lowest cost among other polymeric heaters, and this is a weighty argument in its favor when insulating large areas or a limited budget.

How to insulate the basement of a house outside: step-by-step instructions for the selection and installation of thermal insulation

Insulation of the basement with polystyrene

To insulate the basement, it is necessary to choose PSB-S 25 or PSB-S 35 foam, characterized by increased density and resistance to mechanical stress. The thickness of the slabs varies between 20-100 mm, and depending on climatic conditions, the insulation can be laid in 1 or 2 layers. The material withstands temperature drops from -60 ° C to + 80 ° C without changing its characteristics, so it is not afraid of the most severe frosts and summer heat. The service life, on average, is 25 years, and with a high-quality arrangement of the heat-insulating pie, it will be 10 more years.

How to insulate the basement of a house outside: step-by-step instructions for the selection and installation of thermal insulation

Characteristics of foam

Despite all the advantages, foam also has disadvantages: it has a low bending strength, that is, is quite fragile and is often damaged by rodents.

How to insulate the basement of a house outside: step-by-step instructions for the selection and installation of thermal insulation

Mice gnawed at the insulation

In addition, in the absence of waterproofing, moisture penetrates into the upper layers of the material and, freezing, provokes crumbling of the plates.

Extruded polystyrene foam

How to insulate the basement of a house outside: step-by-step instructions for the selection and installation of thermal insulation

Extruded polystyrene foam

EPS has a denser structure than in foam, and the size of its cells does not exceed 1 mm. This results in almost zero water absorption and greater mechanical strength. Extruded polystyrene foam is also more resistant to chemical attack, microorganisms, shrinkage deformations.

Due to its low vapor permeability, this insulation is not recommended for use on wooden surfaces, but it is ideal for thermal insulation of plinths.

How to insulate the basement of a house outside: step-by-step instructions for the selection and installation of thermal insulation

Penoplex

EPS is in high demand, the most popular are Penoplex, TechnoNIKOL XPS, Styrofoam, TEPLEX, URSA XPS insulation. They are produced in slabs of various thicknesses and densities, standard sizes - 1200x600 mm and 2400x600 mm. The material can withstand temperatures from -50 to + 75 ° C without loss of performance, is easily assembled and lasts for about 50 years, subject to the laying technology.

How to insulate the basement of a house outside: step-by-step instructions for the selection and installation of thermal insulation

TechnoNICOL extruded polystyrene foam

How to insulate the basement of a house outside: step-by-step instructions for the selection and installation of thermal insulation

Thermal insulation Ursa XPS

The disadvantages include the flammability of the insulation - almost all brands of EPS have a flammability class G3 and G4.

When melted, the material releases toxic substances.

How to insulate the basement of a house outside: step-by-step instructions for the selection and installation of thermal insulation

Penoplex combustion

Another disadvantage is the high cost. However, properly executed thermal insulation quickly pays for all the costs with the beginning of the heating season.

Sprayed insulation

How to insulate the basement of a house outside: step-by-step instructions for the selection and installation of thermal insulation

Insulation of the PPU base

Polyurethane foam is at the same time warm , sound and waterproofing of the house. It is suitable for insulating all parts of a building, from roof to foundation, and has excellent adhesion to all types of substrates.

Its main advantage is the absence of seams, since a continuous coating is formed during spraying, strong and durable.

How to insulate the basement of a house outside: step-by-step instructions for the selection and installation of thermal insulation

Seamless insulation of the base

The insulation process takes very little time, the material hardens in seconds and you can immediately start finishing.

The only difficulty is that a special installation and skills to work with it are required to apply insulation. The services of a specialist, like renting an installation, are not cheap, but if we take into account the durability of such thermal insulation, then there is still a benefit. A layer of polyurethane foam with a thickness of 50 mm at a density of 36 kg / m3 replaces an EPSP layer with a thickness of 120 mm, and serves at least 50 years.

How to insulate the basement of a house outside: step-by-step instructions for the selection and installation of thermal insulation

PPU spraying

How to insulate the basement of a house outside: step-by-step instructions for the selection and installation of thermal insulation

External insulation of the foundation and basement

Video - Insulation of the basement with polyurethane foam

Prices for thermal insulation materials

Thermal insulation materials

Do-it-yourself thermal insulation

It is easy to insulate the basement part on your own, the main thing is to follow the technology exactly. One of the most important conditions is the high-quality preparation of the base. If the house is new, the basement and the blind area are in good condition, then the working process will not take much time, which cannot be said about old buildings.

How to insulate the basement of a house outside: step-by-step instructions for the selection and installation of thermal insulation

The facade of the house before insulation and finishing. In the photo, the base does not need preparation

How to insulate the basement of a house outside: step-by-step instructions for the selection and installation of thermal insulation

The base close-up

Preparing the base

Start cleaning the surface from dirt.

If the plinth is finished with tiles or facade panels, the cover will have to be dismantled. They clean off the old plaster, knock down the protrusions, the dried solution, and thoroughly process the base with a stiff brush.

How to insulate the basement of a house outside: step-by-step instructions for the selection and installation of thermal insulation

In the photo, the way to remove old plaster manually

In a brick base, the joints must be carefully cleaned to reveal voids.

How to insulate the basement of a house outside: step-by-step instructions for the selection and installation of thermal insulation

The crumbled mortar from the seams must be cleaned

Next, carefully examine the base, embroider cracks, treat the areas affected by the fungus with special means.

How to insulate the basement of a house outside: step-by-step instructions for the selection and installation of thermal insulation

Cracks must be well cleaned and expanded before repairs

If the blind area is old, covered with deep cracks, it must also be completely removed, otherwise it will not work to insulate the base with high quality.

Next, a layer of soil about half a meter wide and 10-15 cm deep is removed along the perimeter of the house. If the blind area is in good condition and fits snugly against the wall, it is enough to clean the joint along the entire length with a metal brush to remove debris and dirt.

For a snug fit of the boards to the base, the walls of the base / plinth should be as flat as possible. If there are differences of more than 10 mm, the surface should be leveled with plastering. To do this, you can use a conventional cement-sand mortar, but it is better to purchase a dry cement-based mixture.

How to insulate the basement of a house outside: step-by-step instructions for the selection and installation of thermal insulation

Sand-cement mixture for plaster

Factory mixes are more expensive, but they do not shrink and are more resistant to negative effects.The plaster is applied with a trowel to the wall and spread gently over the surface in a thin layer.

How to insulate the basement of a house outside: step-by-step instructions for the selection and installation of thermal insulation

Applying the repair mortar

After drying, the walls are treated with a float with an emery cloth, dust removed and covered with a waterproof primer with quartz filler.

How to insulate the basement of a house outside: step-by-step instructions for the selection and installation of thermal insulation

Plaster grout

Tools and materials for work

For insulation you will need:

  • EPSP boards, for example, Penoplex;

    How to insulate the basement of a house outside: step-by-step instructions for the selection and installation of thermal insulation

    EPSP boards

  • fiberglass mesh for reinforcement;
  • glue for expanded polystyrene (Titanium, Ceresit CT 83);
  • plastic perforated corners with a mesh;
  • dowels-mushrooms;
  • assembly knife;
  • level and tape measure;
  • metal spatulas;
  • drill with mixer attachment and set of drills.

Price for a construction mixer

Construction mixer

It is very simple to calculate the amount of insulation: you need to measure the length of the base according to the entire perimeter, multiply by the height and divide by the area of ​​one penoplex slab.

The material should be bought with a small margin, since the slabs must be trimmed when joining. In the same way, the amount of reinforcing mesh is calculated, which is necessary when plastering the insulation.

Installation of heat-insulating boards

Step 1. Try on the boards to the surface, if necessary, perform a trimming. The lower edge of the insulation should rest on the concrete base of the blind area or on tightly compacted soil covered with a layer of sand.

Step 2. Glue is applied to the back of the first board in a continuous line around the perimeter and in the middle.

How to insulate the basement of a house outside: step-by-step instructions for the selection and installation of thermal insulation

Applying glue

Begin to glue the insulation from the corner: apply the plate to the surface, level it vertically, press firmly over the entire area.

Step 3. Take the next slab, apply glue to the back side and the side edge, apply it to the plinth and fit tightly to the first slab.

If glue comes out at the joint, it must be removed with a spatula. The rest of the sheets are fixed in the same way, controlling the level of their location.

Tip. If the distance to the corner is slightly greater than the length of the insulation, it is better to fix the last sheet in the row close to the corner of the base, and close the gap formed with a segment of the appropriate size. It is undesirable to fasten pieces of insulation in the corner sections due to increased wind loads.

Step 4. After installing the boards, blow out the gaps formed between the insulation and the wall, as well as at the joints of the sheets, with foam. The dried foam is carefully trimmed with an assembly knife so as not to damage the insulation and not move the plates.

Step 5. When the glue dries (usually it takes 24 to 48 hours), fix the insulation with dowels-fungi.

How to insulate the basement of a house outside: step-by-step instructions for the selection and installation of thermal insulation

Drill

Prices for popular models of electric drills

Electric drills

How to insulate the basement of a house outside: step-by-step instructions for the selection and installation of thermal insulation

Drilling a hole for a dowel

Unlike the underground part, where the material is firmly pressed by the soil to the foundation, the aboveground is constantly exposed to wind and mechanical stress, and additional fasteners are essential. Holes for dowels are drilled in the center of each sheet and in the corners, going deep into the wall by at least 40 mm. You need to work very carefully, since the insulation is easy to damage with a drill.

How to insulate the basement of a house outside: step-by-step instructions for the selection and installation of thermal insulation

Installing dowels and driving metal rods

How to insulate the basement of a house outside: step-by-step instructions for the selection and installation of thermal insulation

The joints between the plates are glued with a mounting foam

How to insulate the basement of a house outside: step-by-step instructions for the selection and installation of thermal insulation

Insulated base

How to insulate the basement of a house outside: step-by-step instructions for the selection and installation of thermal insulation

Polyurethane foam that was used during operation

Plastering technology

Step 1. Mix the plaster-adhesive solution by diluting the dry mixture with water according to the manufacturer's instructions.

It is recommended to mix with a mixer at low speeds, since it is more difficult to achieve a homogeneous mass manually.

Step 2. Apply a corner with a mesh to the upper edge of the insulation, measure the required length, cut off the excess. Next, apply the solution with a spatula in a continuous strip, lay a corner, be sure to control the horizontal level. Having aligned the profile, smooth the mesh on both sides, sinking it into the solution.

Remove excess mixture with a spatula. In the same way, the profile is attached at the corners - internal and external.

How to insulate the basement of a house outside: step-by-step instructions for the selection and installation of thermal insulation

Applying glue to EPSP with a spatula

How to insulate the basement of a house outside: step-by-step instructions for the selection and installation of thermal insulation

Angle fixing

How to insulate the basement of a house outside: step-by-step instructions for the selection and installation of thermal insulation

Applying glue to the mesh

How to insulate the basement of a house outside: step-by-step instructions for the selection and installation of thermal insulation

Installing and gluing the corner vertically

Step 3. The reinforcing mesh is cut in width so that it is a couple of centimeters more than the height of the base. You can not cut into pieces along the length, and fasten it with a whole canvas on a flat plane - since the roll width is small, the mesh holds well.

So, an adhesive solution is applied to the surface, it is distributed in an even continuous layer about 10 mm thick, a mesh is applied so that the upper edge is 5-7 mm below the edge of the insulation. Then the mesh is smoothed with a spatula, deepening it into the solution by a few millimeters.

How to insulate the basement of a house outside: step-by-step instructions for the selection and installation of thermal insulation

The mesh is pressed against the applied glue

How to insulate the basement of a house outside: step-by-step instructions for the selection and installation of thermal insulation

One more is applied on top of the mesh with a spatula adhesive layer

How to insulate the basement of a house outside: step-by-step instructions for the selection and installation of thermal insulation

It is important to observe the overlap of adjacent sheets

Step 4 . In a day, when the surface is dry, the plaster layer is treated with a float with an emery cloth, removing small irregularities, sagging, traces of the tool.

How to insulate the basement of a house outside: step-by-step instructions for the selection and installation of thermal insulation

Leveling of dried glue, removing sagging

Then the surface is dedusted and covered with a waterproof primer in 1 or 2 layers.

How to insulate the basement of a house outside: step-by-step instructions for the selection and installation of thermal insulation

Surface moistening

How to insulate the basement of a house outside: step-by-step instructions for the selection and installation of thermal insulation

Plastering process

After that, the dug trench is covered with fine gravel or gravel, a blind area is mounted.The next stage is the finishing of the basement: the surface can be tiled with tiles, artificial stone, pebbles, mosaic plaster looks good.

How to insulate the basement of a house outside: step-by-step instructions for the selection and installation of thermal insulation

Decorative finish of the base

Prices for various types of decorative plaster

Decorative plaster

How to insulate the basement of a house outside: step-by-step instructions for the selection and installation of thermal insulation

In the photo, the base is covered with decorative plaster SPS granite plaster

How to insulate the basement of a house outside: step-by-step instructions for the selection and installation of thermal insulation

Plastering the basement and covering with bark beetle

Video - How to insulate the basement of the house from the outside

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