Hi, I’m in the process of extending a part of the house, which will consist of a hall and a bathroom/toilet. The foundation will be a 10cm concrete slab on 20cm styrofoam with edge elements, embedded water heating coils. I plan to build the exterior walls and the wall between the rooms with LECA blocks, mainly to avoid moisture damage in a wooden construction (always just a matter of time if you’re a bit paranoid) :|
One thing that worries me is the energy leakage; if the LECA wall is on the heated slab, too much heat will escape to the outside of the wall, which becomes unnecessarily expensive. How can this be solved? Can you simply lay out the coils so they start maybe 10 centimeters into the floor, inside the wall? Am I wrong in planning to use LECA, maybe there are better blocks with insulating styrofoam inside? I’m thinking of adding a layer of 10cm styrofoam on the outside of the wall, framing it and putting falun red wood paneling on the outside to harmonize with the rest of the house. Grateful for any input. I may be handy, but I don’t know all materials and methods...
One thing that worries me is the energy leakage; if the LECA wall is on the heated slab, too much heat will escape to the outside of the wall, which becomes unnecessarily expensive. How can this be solved? Can you simply lay out the coils so they start maybe 10 centimeters into the floor, inside the wall? Am I wrong in planning to use LECA, maybe there are better blocks with insulating styrofoam inside? I’m thinking of adding a layer of 10cm styrofoam on the outside of the wall, framing it and putting falun red wood paneling on the outside to harmonize with the rest of the house. Grateful for any input. I may be handy, but I don’t know all materials and methods...
Here you can read a bit about the different types of LECA blocks available:
http://www.finja.se/App_Resource/Page/file/betong/4032-1.pdf
Use insulated blocks for the exterior walls and regular blocks for the interior walls.
The exterior walls should rest on the edge beam in the concrete slab, and there is no underfloor heating in it.
http://www.finja.se/App_Resource/Page/file/betong/4032-1.pdf
Use insulated blocks for the exterior walls and regular blocks for the interior walls.
The exterior walls should rest on the edge beam in the concrete slab, and there is no underfloor heating in it.
Excellent answer! Thank you! The edge beam naturally takes up space and the first loop doesn't automatically appear until a bit in. I had a "bad luck when thinking".
Ergotherm seems to meet my needs. A follow-up question: I'm planning to cover the outside with wood paneling on frames for aesthetic reasons, but should I still plaster the outside? Not too much extra work anyhow...
Ergotherm seems to meet my needs. A follow-up question: I'm planning to cover the outside with wood paneling on frames for aesthetic reasons, but should I still plaster the outside? Not too much extra work anyhow...
If you want to have both belt and suspenders, you can apply a layer of rödgrund on the blocks before the studs to get better water protection (but still capillary open). Very easy to apply, you just mix it to a thin consistency and either brush it on or spray with a funnel sprayer and compressed air.
If you want to do the job properly, you should coat the masonry externally. Leca breathes too well if it is not sealed through coating or plastering. Additionally, you lose much of the good fire resistance the masonry gains if it is sealed.
LECA blocks are terribly porous, so I would also, as Gallimatias says, render or plaster the outside, and I would additionally render the inside.
You mean if it isn't sealed?Gallimatias said: