Why do we need 30 cm

I'm talking about insulation of the attic. For our climate, according to SNiP, 20 cm of insulation is enough. And we live almost in Kursk, in the village. In a townhouse, as it is now fashionable to call a house for 2 families.

Why do we want to "eat" the extra 10 cm of usable area of ​​the attic, spend a lot of money on insulation and work? There are 3 reasons.

The first reason is the idea of ​​a super warm home

Our wall is like this:

• Outside half a brick of silicate
• 40 cm of penoizol (I was not mistaken)
• Half brick red inside. Naturally, with a dressing.

We poured it ourselves, bought the installation, delved into all the subtleties and poured it in.

The idea was to make the house extra warm in order to spend a minimum on heating. If you are interested, we will talk about such walls in another article, now I will continue about the attic.

We started to insulate it only this summer. For five years we lived with a covered flight of stairs (30 cm of mineral wool and wind protection). And in the wooden floor there is 20 cm of penoizol.

The width of the wall can be seen in the photo:

The walls paid off. We didn't have batteries on the 1st floor, only a warm water floor. We often put it on the igniter so as not to fry.

So, if we insulated the roof slopes by 20 cm, nothing would remain of the idea. Tried-tried:

• The floor was insulated
• The walls were insulated
• The gables were insulated - it's all money too!

And all this will lose its meaning if you do not insulate the slopes with a layer of 30 cm mineral wool.

True, the partition with the neighbors in the toilet and bathroom was insulated only by 15 cm plus half a brick, technologically it is no longer possible, the holes for pipes and plumbing are not designed for more powerful insulation. The neighbors' attic remains cold. So the ideal is still unattainable :)

Reason two - noises and summer heat

Our roof is made of metal tiles. It is reliable, but it was very noisy in the rain and hail. Plus, it's very hot in the heat. I read in the comments of the kuryans that they have 20 cm and are not noisy and not hot. So it depends on what the roof is covered with, and maybe it cools under the trees. We have a clear field.

Windows in the gables to the north.

Specifically, throughout the hot summer of 2021, we had 20 cm of mineral wool, like this:

By the way, we need just such a green one for insulation, they bought in Leroy

It so happened that they insulated the beams by 20 cm, as everyone does, and then force majeure began, only in winter there is hope to continue. The result was not a theoretical, but a practical answer to the question, is 20 cm of mineral wool enough from the heat if the roof is made of metal?

I can say for sure that it was hot and noisy in the attic in heavy rain. Although not as much as in previous years. Obviously, the last 10 cm makes sense.

Which is better, a hot room 10 cm larger, or a comfortable one 10 cm smaller?

The third reason is technological

As you can see, the mineral wool is sewn up with boards:

It is wrong to attach drywall to the boards, the tree will "walk". The technology of fastening the insulation has not yet fully understood when they will do it, I will show you if you are interested.

Metal hangers (plates) will be attached to the wooden parts, and insulation on them. Ultimately, the suspension is the letter Pe. Insulation inside. Then the vapor barrier. And then drywall racks and drywall itself are attached to the suspensions.

There are three reasons. Among our acquaintances, few understand why this is necessary. And who in the subject, they say that this is a very good decision.

As for money, people are ready to spend it on such nonsense! And no one will say a word to them. Is it really impossible to invest in normal insulation?

I would be grateful for your subscription and communication :)