ᐅ Contractor recommends T7 mineral wool insulation

Hello everyone,

Yesterday, I had a very interesting conversation with a construction company. We spent a good three hours discussing our ideas and expectations.

Regarding the wall structure, they had a clear opinion: they do not recommend a 24cm (9.5 inches) wall (or similar) with external insulation. Instead, they suggest a 36.5cm (14.4 inches) T7 wall with mineral wool insulation. In my opinion, this is significantly more stable in terms of wall thickness (especially concerning anchors and general wall fixtures) compared to a T10 (or similar).

The information above is based on using a gas heating system, although we are still unsure about what we want in that regard. In my opinion, I would rather invest more money in the wall structure than in the heating system at this point.

What do you think? Is a gas condensing boiler combined with a T7 wall and mineral wool insulation a good combination?

By the way, it will be a two-story house with about 160m² (1,722 sq ft).

Quality means meeting your requirements – then comes the price. Get a quote. In some other forums, people tend to swear by perlite insulation for the T7. Each supplier understandably recommends the product they have (good) experience with.

Besides bricks, there are other building materials as well (sand-lime brick, aerated concrete, wood). But this often leads to fundamental debates.

1. Define your requirements – you can also consult experts here (insulation, soundproofing, wall thickness, sustainability, installations)
2. Request quotes for solutions that meet these requirements
3. Compare and decide

Hello,

this is definitely a solid combination, but you need to consider more precisely what you want it to be solid for.

Are you aiming to meet a specific KfW standard?

I can’t really say if a T7 with mineral wool insulation is actually more stable, since the raw density class of T7 mineral wool is even lower than that of T10. These materials have roughly the strength and consistency of puff pastry. So, if you want to hang a cupboard, you will need special plugs or anchors anyway.

Best regards,

Andreas

However, the bulk density may also be due to the wool. I believe the ribs themselves are wider, right?

Obviously, the ribs are wider than on the T10; I had both lying next to each other.

We are not planning a KfW house.