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Rendering on polystyrene - which type? Moisture risk between polystyrene glued directly on Leca?
I have a newly built sloping house with a wall in red-plastered masonry leca. This wall will end up under a terrace and is completely above ground. The rest of the house is wood.
I was recommended by the mason to glue on styrofoam in the simplest way, so I did that in the spring. I put a few golf ball-sized blobs of PL200 per sheet and pressed them in place, it went fast and it was fun. Two overlapping layers of 100mm styrofoam (maybe I should have had a proper air gap?), finished with a 200mm edging strip at the top. That's how it stood over the summer. At first, I thought I'd leave it like that since the wall wouldn't be visible from outside. But now I want to do something since the surface of the styrofoam is starting to take damage even though it will be under the deck floor. It's worth mentioning that it will be a (cold) storage room there.
1. Is there a risk that I might have moisture problems later on since I don't have a proper air gap in the wall? If I did it over, I'd probably have used grooved styrofoam on the inside, I think... Or platon.
2. I'm considering plastering the styrofoam, if it doesn't increase the risk of moisture. What type of plaster should be used for this?
I was recommended by the mason to glue on styrofoam in the simplest way, so I did that in the spring. I put a few golf ball-sized blobs of PL200 per sheet and pressed them in place, it went fast and it was fun. Two overlapping layers of 100mm styrofoam (maybe I should have had a proper air gap?), finished with a 200mm edging strip at the top. That's how it stood over the summer. At first, I thought I'd leave it like that since the wall wouldn't be visible from outside. But now I want to do something since the surface of the styrofoam is starting to take damage even though it will be under the deck floor. It's worth mentioning that it will be a (cold) storage room there.
1. Is there a risk that I might have moisture problems later on since I don't have a proper air gap in the wall? If I did it over, I'd probably have used grooved styrofoam on the inside, I think... Or platon.
2. I'm considering plastering the styrofoam, if it doesn't increase the risk of moisture. What type of plaster should be used for this?
1. No, there should not be any moisture problems with this solution since it is above ground.
2. See e.g. Finja's instructions for Iso Fin:
http://www.finja.se/App_Resource/Page/file/betong/5017-1.pdf
The plaster mortar is usually fiberglass-reinforced when plastering on foam plastic, Finja's is called FGB 8500.
2. See e.g. Finja's instructions for Iso Fin:
http://www.finja.se/App_Resource/Page/file/betong/5017-1.pdf
The plaster mortar is usually fiberglass-reinforced when plastering on foam plastic, Finja's is called FGB 8500.
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