Insulation for exterior walls: 3 ways to save on heating

Gusevsky Andrey Anatolyevich

The photo shows the process of warming the exterior walls of the house

Heating a house in the winter can be a significant cost to the family budget, so more and more people are thinking about how to save money on it.

In this article we will talk about external insulation for walls, and open three ways to significantly save on heating. Of course, initially you will have to spend, but all investments will pay off in two seasons, and already in the first winter you will feel how much your expenses have been reduced.

What you need to know about insulation

We see several different materials that are used to warm the exterior walls of the house.

The main difficulty in choosing a thermal insulation material is a huge variety of options on the market. All of them have their pros and cons, and it is impossible to specifically single out one thing and say that this is the best type of insulation. It is selected based on many features, but there are qualities that must certainly be present in any material.

So, let's figure out what no modern insulation can do without:

• Save form. The main quality that an external insulation for walls should have. The better the material holds its shape, the easier it is to work with it.
• Moisture resistant. Regardless of the facade finish, the insulation is constantly exposed to moisture, whether it is precipitation or condensation.
• Incombustibility. Most modern outdoor heaters include flame retardants that prevent the spread of fire. In no case can one save on this nuance.
• Easy installation. Quality is important if you plan to do it yourself. Some materials cannot be applied without special sophisticated equipment.

You can warm the exterior walls of the house yourself, without special skills

• Vapor permeability. An important factor for all types of building or finishing materials, and insulation for walls is no exception.
• Heat capacity. An indicator that only specialists can calculate, and if you do not want to contact them, it is best to make a small margin of the thickness of the insulation layer.

To one degree or another, these qualities are present in all materials, but we have specially selected for you the most popular options in which they are concentrated as tightly as possible. So, let's start with the most inexpensive and popular option.

Cotton-based insulation

We see the process of warming the walls of the house with the help of a cotton insulation

The most popular and widespread insulation for external wall insulation today is cotton wool (see.How is insulation of walls outside with mineral wool) Its main distinguishing quality is the price, which is significantly lower than that of materials based on styrene or polyurethane.

Unfortunately, it is far from always possible to use cotton wool as a heater, and its ability to fall into lumps becomes the main problem. Of course, this can be avoided by more frequent fastenings, but this is not always possible. Cotton insulation can be divided into two types.

Mineral wool

We see the insulated walls of the house with mineral wool

Mineral fiber based material. Often it is confused with glass wool, known to everyone, but this is erroneous, since mineral wool has nothing in common with it except for appearance.

Of the advantages of this material, there are several of the most significant:

• Resistance to fire.
• A light weight.
• High degree of thermal insulation.
• Vapor permeability.

Unfortunately, mineral wool can accumulate moisture and become heavier and stoop over time, and this can be considered its main disadvantage.

Basalt

The process of wall insulation with basalt cotton slabs

Basalt cotton wool is produced with the addition of natural volcanic basalt to the composition of the fibers. Such a material is much more expensive, but its quality characteristics are higher than that of mineral wool.

First of all, it is the ability to maintain their original shape even with a high level of humidity. Water is not able to make cotton so heavy that it loses its shape.

Moreover, basalt has a wider temperature range, so it is often used to warm the walls of furnaces or heating boilers. Also, basalt cotton wool is used in sandwich panels from which frame houses are built.

Important! Visually, basalt cotton wool can be distinguished from mineral wool only in color. Mineral wool is yellow and basalt gray. This is a nuance used by many unscrupulous manufacturers, so when choosing an external insulation it is better to give preference to a well-known manufacturer that you can trust.

Styrene insulation

The process of warming the exterior walls of the house with styrene heaters

Styrene is a chemical product. Its most famous manifestation is polystyrene (seeHow is the insulation of the walls with polystyrene foam done outside), which in the past was used only as a package, as it had very high flammability and toxicity.

Modern technologies have allowed significant changes to be made in the production of styrene insulation for walls, and now they not only do not burn on their own, but also prevent the spread of flame, since at high temperatures they decompose into water and carbon dioxide.

Styrofoam

Very lightweight foam material, holds heat well

A significant disadvantage of this insulation can be considered a complete lack of vapor permeability. But the foam is maximally resistant to moisture and does not lose its qualities under temperature influences.

Fastening the foam to the wall can be done in three ways:

1. On glue. Due to its light weight, any cement-based adhesive is suitable for attaching the foam. You can use glue for drywall or tile.
2. On plastic dowels with wide caps. The most time-consuming method, but only for wooden walls.
3. On mounting foam. Foam is applied to the foam plate, after which it is firmly pressed against the wall. Foam cures very quickly, so the whole process does not take much time.

Penoplex

In the photo we see an example of penoplex

Another type of styrene insulation that differs from polystyrene in grain size and density. Penoplex is a very solid and durable insulation, so it is often used not only on walls, but also as insulation for floors and roofs.

It costs more than its older brother, and like it, penoplex does not have the ability to let off steam. Also, due to its high density, with the same heat capacity of the foam and foam, the thickness of the second plate will be several times smaller. And if with external insulation this factor is not particularly important, then in internal work it is often it that becomes fundamental.

Advice! If you need to cut the foam plastic tile, be sure to protect the cut edge with special impregnation, since it is from there that moisture absorption will begin.

Polyurethane foam

We see an example of a polyurethane foam in the context

A relatively new insulation for external walls, applied by spraying from a special compressor unit (seeLiquid thermal insulation for walls: features of use) If we talk about the shortcomings, then we can highlight only the complexity of the application. More precisely, without a special expensive mixer, nothing happens at all.

We will not describe in detail the process of applying PPU, since the topic of our article is not this, so we just suggest you watch the video in this article, which shows detailed instructions for working with this material.

The process of applying polyurethane foam to the exterior walls of a house

Important! If polyurethane foam is used as insulation for walls outside under siding, then after applying it, it is necessary to allow the foam to completely harden, then remove its excess, and only then begin fixing the finish. The fact is that the foam expands significantly when it dries, so it can simply squeeze out the siding panels.

It is worth noting that PPU is the only insulation for external multilayer walls. One of the methods of its application is injection into the wall through special technological holes. Therefore, if you built a house, and in the end it turned out that there is not enough insulation, then the easiest way is to use polyurethane foam.

And in conclusion

This is how the walls of the house look insulated with polyurethane foam

As we said above, our article will not give you an answer, what is the most optimal insulation for an external wall, but it will help to better understand the difference between the materials, and to arrange the information, let's put it in a comparative table:

As you can see, the characteristics of these materials are different, and that is why there can be no clear answer which of the insulation is better. It all depends on the characteristics of your home and its walls.