Basement damproofing -Synthaprufe


16 Mar 2016
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United Kingdom
Hello all

I'm currently damp proofing my basement. I have hacked off the plaster and intend on applying Synthaprufe to tank the walls. The masonry walls aren't in great condition, is it advised that I stabilise the walls before applying the Synthaprufe or is there no need?

Also, there are a couple of sections that aren't too damp and I've left plastered. Can I apply the Synthaprufe straight onto the plastered walls?

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AS I recall you need to paint a diluted coat of Synthaprufe on first that acts as a primer.
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Tanking the walls with Synthaprufe is a shot in the dark.
For a start its better to remove all plaster back to the brickwork, and tank three coats onto the walls. Dont apply over the remaining plaster.
What condition are the walls in? Are they wet, is water penetrating them? Is the brickwork crumbling?
Successfully damp proofing a basement can be a complicated business involving a number of other considerations, all of them important.
Why not search"basement tanking" on here?
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Cheers Footprints - I thought that as well but cannot find anything from Iko saying that.

The walls aren't in too bad a condition, i think the damp was the product of poor ventilation rather than water ingress. Is it ok to apply the Synthaprufe directly onto the walls without stabilising?
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Well the last time I used it was on a concrete floor back in the 70's prior to laying a wood floor above!:)
At the time I think it was water based and dilution was about 10%, contacting the makers direct might be the best move.
I would have thought there are a lot more products on the market these days that are designed for tanking, synthaproof was a general purpose bitumen product used for coating pipes etc before screeding as well as waterproofing.
Might be best posting on here with a couple of photos to ask what product is recommended, as far as sealing I would have thought as long as loose material is removed the diluted coat will work.
I tanked a room with Synthaprufe and dislike it because it remains sticky (use baco foil on floor afterwards?). Also blinding it with sharp sand prior to plastering is actually difficult to get it evenly rough. Doing it again I would use SBR and cement, with a little sharp sand for the last coat.

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