Hello,
In the basement, there are currently basement walls made of concrete block (1945).
I would like to reinforce and possibly make it a bit warmer by building new basement walls inside the old ones. Probably with Leca. The reason for all this is an extra floor on the house, and I want to make the basement warmer and refreshed. It's quite miserable right now.
How should I best attach the new Leca wall to the old concrete block wall? I have tried blasting off old plaster with the pressure washer, it went really well (160 bar), and what's left is a very rough surface with plenty of grip.
Another question, is there any disadvantage to insulating a bit from the inside with Leca, about 15-20cm?
In the long run, there will probably be external insulation as well.
In the basement, there are currently basement walls made of concrete block (1945).
I would like to reinforce and possibly make it a bit warmer by building new basement walls inside the old ones. Probably with Leca. The reason for all this is an extra floor on the house, and I want to make the basement warmer and refreshed. It's quite miserable right now.
How should I best attach the new Leca wall to the old concrete block wall? I have tried blasting off old plaster with the pressure washer, it went really well (160 bar), and what's left is a very rough surface with plenty of grip.
Another question, is there any disadvantage to insulating a bit from the inside with Leca, about 15-20cm?
In the long run, there will probably be external insulation as well.
The most logical approach is to create a cavity wall, i.e., place insulation between the concrete hollow blocks and the leca blocks. The leca blocks themselves insulate at about 25-30% of the capacity of mineral wool. The execution naturally depends on how thick the leca blocks you intend to use are.
Hi,J justusandersson said:
In this case, I want to reinforce and integrate the new basement wall with the new basement wall into one. I've been considering whether to have a 1cm gap and then fill it with flowable lightweight concrete. Or if I should just apply cement mortar on the back of the lecablocks to make them adhere to the old basement wall.
I believe more in a small gap. If you have plenty of time, you can attach cramps into the concrete perforated bricks that you then build into the joints between the leca blocks. However, I don't think it's necessary unless you plan to use very narrow leca blocks.