Now I think that the waterproofing layer doesn't let through so much that the particle board behind it will look like the one you're thinking of. And if there's that much moisture, you probably have much worse problems than just the particle board....Fotografen said:
I assume, though without knowing, that råspont starts to mold at the same RH as particle board, that's what I find illogical.
Some leakage does exist THROUGH the waterproof layer since it is not completely sealed. This moisture is what we are talking about, I assume? Whether the particle board can handle this or not is probably what's interesting.
If you get LARGE leakage, everything must be torn down regardless of construction, I assume.
My particle board (60mm) did not handle moisture very well anyway, it was 100% rotten in parts.
If you get LARGE leakage, everything must be torn down regardless of construction, I assume.
My particle board (60mm) did not handle moisture very well anyway, it was 100% rotten in parts.
But it feels a bit strange that it's not supposed to be okay with particle board as the second layer in the wall but at the same time it's okay in the floor! Now it's probably going to be about placing double DryCo by the shower and bathtub, so no one can say anything, lucky they aren't too expensive...
The chipboard can handle the minor moisture migration that occurs through the waterproof layers, undoubtedly. It is rather the risk of leakage at poorly sealed penetrations that BKR is concerned about. These are never present in floors, which is likely why chipboard in floors is permitted. Plus, there are no reasonable alternatives to floor chipboard.
If you have cement-based boards like Masterboard as outer boards, is it then okay to have OSB as inner boards??
Well, that's just great... That wasn't what they said in the plumbing store when I was building the bathroom. "Chipboard behind the plasterboard is perfect, then you've got something to screw into."ACME said:
However, this was before the new regulations came into effect.
On the other hand, has bkr paved the way for interpretations or not? It's a bit ambiguous.
BBV 07:1
5. BASE
5.1 General requirements
Wall and floor bases intended to be
bases for mounting ceramic tiles in
wet rooms should primarily be of a non
moisture-sensitive nature, i.e. stable
after moisture application. If this is not the case
the base should be replaced with, or supplemented
by, non-moisture-sensitive material.
However, it further states...
5.7.1 Walls
Wood-based panels should not be used in ceramic
wall coverings.
In PER 99:1 the terms "wall covering" and "base for ceramics" are used, and how do you interpret that? The chipboard behind the plasterboard is not the direct base for the ceramics.
Then we have old threads where chipboard seems to work excellently under the plasterboard. But maybe it was okay before.
http://forum.byggahus.se/badrum/75222-redan-fragor.html
I know that plasterboard is not allowed anymore. However, I find the industry's regulations a bit vague, and I cannot find text that directly explains that chipboard behind a "waterproof" board is not allowed. Or that raw chipboard would be allowed for that matter.
Yes, it's a bit vague. But "wood-based boards should not be used in ceramic wall coverings" is what applies, and that means not only the outermost board, but it applies to everything on the wet room side of the studs. It does not say that raw plank is allowed, but it does not say that it is not. It would be tricky if wood in a wall construction was prohibited, it would be difficult to build bathrooms in most houses then.
That the building trade doesn't give a correct answer doesn't surprise me, but in this case, it's not so strange if you asked before the new regulations came.
That the building trade doesn't give a correct answer doesn't surprise me, but in this case, it's not so strange if you asked before the new regulations came.
Practically yes, regularly no. And the implementations are still a risk point. Therefore, the shavings work just as well behind the plastic as if there were no plastic at all. But it would not work between plastic and waterproofing.