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Damp Proofing Question
Laying engineered wood in basement flat
I have commissioned a flooring company to lay engineered wood flooring in an old basement flat.
The previous solid wood flooring buckled (however there was a burst pipe to the rear of the property which has now been fixed).
As the floor was old, damp and uneven the flooring company have
1) Used a PVA and then a self levelling compound (Universal Setcrete )
Their next steps are to
2) Lay a liquid DPM wait for this to dry
3) Lay a plastic sheet, then put a fibreboard underlay
4) Lay the new engineered wood flooring
However, I was concerned as 36 hours later the self levelling compound is not fully dry. It was supposed to take 3-24 hours. As such I had a look at Universal setcrete website and it states a DPM should have been laid beneath the self levelling compound.
My question is - who is right? Should the DPM be laid before or after the Self levelling compound?
Should I ask the flooring company to take up the self levelling compound and start again by installing the DPM? Should the DPM be liquid or physical? My surveyor had suggested Oldroyd xs rather than a liquid one to prevent human error causing cracking.
Please see Stages 1 - 5 below
1 / DPM Sheet 1200g
2 / Level Compound
3 / Oldroyd Xs DPM
4 / Underlay
5 / Wood Flooring
What they are doing is
1 / Applying PVA to the base
2 / Laying level compound straight on to an unknown damaged floor base
3 / Adding a liquid DPM
4 / DPM sheet under the underlay
5 / Underlay
6 / Wood Flooring
Besides your surveyor had suggested the use of Oldroyd xs rather than a liquid one to prevent human error causing cracking.
Hope this helps.
Blank Canvas Constructions
Answered 4th Apr 2015
I'm not a builder, but have laid plenty of floors in old vicorian properties, usually with underfloor heating, some wet, some electic.
For me, I have used liquid Dpm a lot, and have always put it directly over the concrete sub floor. ( taken it up the walls where necessary ).
Whenever I have used the modern self-levelling compounds, I have mixed them with water, then poured !
So to me, it would suggest that they are not waterproof, and would be hydroscopic, thus drawing up the moisture.
Hence, should be poured above the Dpc !
I would have used, liquid Dpc, cement board, (say Baker board ), which both helps to level the floor and provide some insulation.
Then the heat mat, ( if required), set in self levelling compound.
Then tiles / wooden floor / vynal over !
Answered 5th Apr 2015
totally agree with blank canvas, not many of us about
Answered 23rd Apr 2015