Instafoam cavity insulation

[Maurice]

Looking to move soon, the survey done on a bungalow reports slight dampness low down on the inside of some external walls. The building was cavity insulated with Instafoam in 2007. Anyone know of any dampness caused by Instafoam (which has a 25-year warranty).

The possible cause suggested by the surveyor was that the damp-proof course was less than 150mm from the surrounding ground (which is currently only 75-100mm below), so the ground level needed lowering.

Can anyone here recommend a UK damp specialists who could check the situation and give a diagnosis?

[Tim Watts]

On Thursday 26 September 2013 21:44 Maurice wrote in uk.d-i-y:

My DPC is 2" above ground - unless yopu get a lot of water splashing up or major floods in rain, that alone should not be a problem.

Is it really damp? And no - sticking a damp meter in tells you exactly nothing in masonry.

Any mould or discolouration of the inside wall in the region?

>

[Martin Bonner]

That is a very good question. However it may be trumped by the building society making it a condition of the mortgage that the damp is dealt with.

Another possible cause is condensation on a cold wall - if the cavity fill missed a bit, that bit would be cold, and, hey-presto, condensation and damp.

[harryagain]

There is no such thing. They will all find some problem or other which only they can (expensively) fix. I wouldn't worry. When you get some heat on the place it will likely disappear. Probably a bit of condensation. Rising damp is not as common as is touted. Buy an el-cheapo damp meter and you can play around with it. The damp will likely disappear in a month or so spontaneously.

[meow2222]

For once harry's mostly right. Damp specialists are mostly... well, think of Arthur Daley.

If there's a damp problem there will be symptoms you can tell us. Otherwise there is no problem.

You forgot to tell us the age of the building

NT

[Maurice]

1965 or so.

We've found the cause: The owners had built up the ground by the wall so that the damp course was only 75-100mm above ground level (instead of the regulation 150mm), AND had placed plants all around the outside walls, AND had a sprinkler system that watered the plants!!!