How to insulate an old house? Practical advice

Table of contents

• How to insulate the foundation in an old house?
• How to insulate an old house above the foundations?
• How to insulate the attic in an old house?
• Is it worth insulating an old house?

Recent months have been marked by skyrocketing heating costs. No wonder that many people are starting to look for ways to reduce them. A way to do this is to insulate an old house, which pays off primarily in the long term. How to plan such activities? We encourage you to read it.

How to insulate the foundation in an old house?

The first step is to insulate the foundations of the old house. After digging them up, cleaning them and filling in the gaps, you should first deal with hyroisolation. A special bituminous enamel, which is a sealing primer, will work well for this purpose. Only then should the proper insulation be laid to protect the building from moisture.

When it comes to insulating the foundations of an old house, styrodur is commonly used. It is a material with good properties and high density, additionally waterproof and durable. What thickness should it be placed on? The optimal is from 5 to 10 cm, although here many investors are limited by the price, which in the case of this material is unfortunately not low.

Also check out our practical ways to increase energy savings at home.

How to insulate an old house above the foundations?

In this case, proper preparation is very important. When deciding on a new façade, the condition of the plaster is crucial. It can only be laid if the plaster does not crumble and does not fall off the wall, and also adheres to the substrate in a good way.

You also need to choose the insulation material in the right way. Of course, polystyrene is popular, as it is cheap and easy to process, as well as resistant to moisture, so it may work better in older buildings. Wool, on the other hand, is more expensive, but vapour-permeable. Any of the materials will therefore be good, and the final choice always depends on the investor’s finances.

There is also the question of what the thickness of polystyrene should be to insulate an old house. It should be between 10 and at least 15 cm. Contrary to popular belief, 3 to 5 cm is not enough to achieve the right coefficient in this regard and ensure thermal comfort inside.

How to insulate the attic in an old house?

Insulating the attic is a great way to additionally develop it. However, in order for it to be suitable for staying, it needs to be insulated. Here you should immediately bear in mind that up to 30 percent of heat escapes through the roof. This makes the issue all the more important.

There are several methods here, and one of the most commonly used is mineral wool. It works primarily because in the summer it will not be too hot in the attic, which would make it difficult to stay comfortably. To additionally ensure adequate insulation, you also need to take care of placing a vapour-permeable foil, which allows you to minimize the level of moisture.

But how to insulate the attic? If the attic is unusable, then the insulation of the ceiling itself is sufficient. For this purpose, you can use mineral wool, which is spread on the surface so as not to leave spaces through which heat would escape.

Is it worth insulating an old house?

There is also the question of whether it is worth insulating an old house at all. In general, the answer is: yes! This is especially due to rising fossil fuel prices, which should encourage this. It is also a great solution in multi-generational houses, often renovated inside, to adapt them to be inhabited by a larger number of people.

From our blog you will also find out whether it is worth renovating an old house. Also check what advantages energy-efficient houses have and why their construction is so popular nowadays.