Insulation of a pile foundation of a wooden house: how to insulate the base

Insulation of a pile foundation is usually performed with expanded polystyrene or liquid foam insulation. Other materials with good thermal insulation properties are also available, such as penoplex. There are 2 technology options - the construction of a base made of brick and decorative panels. Both instructions are presented in the article.

Choice of insulation and waterproofing

Before you start insulating the pile foundation of a wooden house, you need to select a material. This is a very important decision, which largely determines the effectiveness of frost protection. There are several options:

1. Foam plastic is durable, resistant to pests, mold, easy to install and very affordable. It is characterized by its low weight, low density and at the same time good thermal insulation. However, it is not very durable, so it needs a reliable layer of external protection.
2. Another way to insulate the pile foundation of a wooden house is using penoizol in liquid form. The basis of this material is urea resin; it also contains a hardener and foaming agent. The liquid mixture is poured directly into the formwork, where it quickly hardens. The material is of very high quality and can withstand almost any temperature and humidity.
3. When studying how to insulate the base of a house on screw piles, you need to consider the option of foam glass blocks.It is light, very durable, and completely impervious to water pores. In addition, it is resistant to rotting, chemicals and fire. Serves for more than 50 years.
4. Insulation of a pile-screw foundation can be done using extruded raw materials - penoplex and expanded polystyrene. Unlike polystyrene foam, they are much denser, practically do not absorb moisture and at the same time are lightweight. Resistant to rotting, not afraid of rodents. However, they deteriorate due to the rays of the sun, so it is important to create reliable external protection.

When learning how to insulate a pile foundation, it is worth taking care of high-quality waterproofing. In fact, any insulation can be damaged by moisture. Water can also cause corrosion of the screw pile head. Therefore, it would not be superfluous to carry out treatment with the following types of water protection:

1. Coating - mastics based on bitumen with or without the addition of rubber.
2. Rolled - film or bitumen material, for example, classic roofing felt, glassine.
3. Painting – compositions with hydrophobic substances, bitumen primer.
4. Impregnating – bitumen-based resin or liquid glass, suitable for any concrete surfaces.
5. Actually, mastic is based on polymers, bitumen, rubber and a combination of these components. It is applied using hot or cold technology.

Step-by-step instructions for insulation

Insulating the basement of a house on screw piles always involves the construction of a false base. In fact, this is an additional external frame, a small wall that completely covers the piles, reaching the first floor. It can be made from brick - it will be a permanent structure.

Also, insulation of the base on screw piles can be done using sheet materials that are attached to the sheathing.It is easier to install and is optimally suited for heaving soil, on which it is impractical to build a brick wall (it may become deformed). Both options are described sequentially below.

Brick base

If you insulate the base of a pile-screw foundation using this technology, you will get the most reliable structure that will last for several decades without any complaints.

The main stages of construction are as follows:

1. A trench 25 cm deep and 40 cm wide is dug along the perimeter of the building.
2. Formwork made of boards is installed in it. A frame is mounted from reinforcement rods.
3. When the structure is ready, concrete is mixed and poured into the formwork.
4. Insulating a foundation on piles takes more than one week, because the concrete must be allowed to completely harden. After this, the formwork can be dismantled.
5. Now the concrete is covered with a layer of waterproofing. It can be roofing material or mastic based on polymers or bitumen.
6. Lay the brickwork on the concrete in 1.5 m fragments. Gaps are left so that later insulation can be laid from the inside.
7. Next you need to go through plaster and primer.
8. After this, cladding is done using any material, for example, lining or siding.
9. Insulation of foundations on screw piles involves the use of penoplex or other material. Be sure to install a vapor barrier membrane and fix it with glue, for example, Ceresit ST83.

Base with decorative panels

This method of insulating the pile foundation of a frame house takes less time, and the materials are more affordable. You need to do this:

1. The piles are treated with mastic and an antiseptic.
2. Several rows (usually 3) are mounted horizontally with guides made of steel profiles.
3. Panels are fixed to them, on the reverse side of which there is already insulation material. Instead, you can use DSP boards.
4. If the soil is heaving, you should leave a gap from the ground at a height of 5-10 cm.
5. In order to properly insulate the pile foundation of a wooden house from the outside, ventilation is carried out.
6. Then the finishing is done and the gap is covered with decorative strips.

Further work boils down to installing thermal insulation outside and inside. For work on the street side, polystyrene foam is usually used because it is resistant to any weather conditions, temperature changes and humidity.

It is worth considering that insulating the grillage of a pile foundation also involves thermal insulation of the blind area. Special attention is paid to the floor - it is also insulated with polystyrene foam from the inside or outside. At the same time, it is better to carry out work on internal insulation during construction.