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Damp, condensation, ... why are things not drying out?

Postby helpmeimagirl » Tue Mar 09, 2010 11:25 am

Hi all, I am hoping someone will be able to help me. I apologise in advance for the long post but want to try and provide as much info as possible.

Have recently bought a 1900s terrace, around 5 months ago had DPC installed all around the kitchen, internal and external walls. Old kitchen had been ripped out, kitchen was then replastered and new kitchen fitted a couple of weeks after the plastering.

A month or so ago I noticed a musty smell behind fridge (against external wall). Pulled it out to find pipes soaking wet, bare plaster damp and mouldy. Cleaned it up, lagged the pipes, painted the wall incase it was absorbing moisture. Has stayed dry, but noticed more damp behind and under cupboards next to fridge (sink cupboard, under window, in corner of two external walls), pulled plinth off and its pretty manky under there, fluffy mould on concrete floor and where exposed bricks join the new plaster. Investigated further and mould in cupboards at bottom. Back of cupboards are wet from the bottom (unit is on legs a few inches above the floor) a couple of inches up. Feeling the (again bare) plaster behind the cupboard, seems dry, but the run of exposed bricks between the floor and the new plaster, where the DPC was injected, are soaking. Cleaned up at the weekend, dried, removed mould, and today they are wet again.

Had a builder round when first noticed the damp and he concluded a ventilation problem (this did not surprise me, hood is on internal wall so just recirculates, but do always cook with kitchen window open). Had extractor fan fitted on external wall with a humidity sensor, have set it to 50% but this does not trigger until its really steamy in there so not overly effective whilst cooking, just clears it quicker after. By this point the moisture has already sat on the walls so a flashy extractor does not appear to be a good investement :(.

Can anyone suggest why it is so damp at the base of the wall behind the cupboards? The floor level in the kitchen is a good foot higher than the ground outside, so I'm pretty sure its a problem inside. Under the cupboards the floor seems to be concrete, as the plywood and tiles don't start under there. There is a plastic membrane underneath, you can see the overhang at the sides.

If it is still a condensation problem, how can I increase ventilation even further - two extractors running and the window open doesn't seem to be doing the trick. Airbricks?

I am concerned that in hindsight, the kitchen was fitted too soon after the DPC work and replastering so was not fully dry. Could this be contributing? If so can I do anything?

I honestly don't know what to do. My kitchen is brand new but looks a mess because of all of this. I am not keen on getting the firm who did the DPC back unless I know there is something wrong with what they did - I guess I will try get an independent damp expert round but wondered if anyone had any ideas from the info provided.

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Simply Build It

Postby stoneyboy » Wed Mar 10, 2010 9:05 pm

"the kitchen was fitted too soon after the DPC work and replastering so was not fully dry" almost certainly yes.
There should not be exposed bricks as you describe the walls should have been covered with a cement render up to about 1m before plastering.
Can only suggest you hire a de-humidifer (with re-heat) and run this 24/7.
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