Basement damp

[nog]

We have a basement below about one-third of the house and its usefulness for storage is limited by damp, and resulting mould spores. We've tried to combat this by using a de-humidifier but I suspect the net result of this is to accelerate the rate at which water is vapourising through the walls. Would we have more success by installing one or more extractor fans to pull air through? The floor area in question is about 45 square metres, split between two rooms, with a ceiling height of about 2 metres. The remaining space under the house is just crawl space, although fairly generous in headroom. The house was built around 1910.

TIA,

Peter

[stuart noble]

Unless you can seal off the moisture source, I think any of the above will be a waste of time

[N. Thornton]

Yes, and much cheaper to run. Downside is youd lose any heat down there, and heat isnt free.

Better than fan is unfanned ventilation: if you can arrange it its silent, reliable and costs nothing to run. Need 2 openings for the air to blow through, 1 opening isnt gonig to achieve much - same with fan.

If its just a case of the dehumidifier not being effective enough, I imagine a ceiling fan on low would help a fair bit - have never tried that, but I would thihk it would.

Another option is to tar the walls, then the space would be far more useful. There are also clear waterproofing compounds available for sound substrates.

Regards, NT

[timegoesby]

It is best to eliminate the damp at source. If it is coming through the walls and floor, get it tanked. I read in a building magazine a number of years ago, that it is feasible to build stud frame walls and floors that do not touch the walls. Any part of the frame that does must have poly damp course behind and only stainless steel screws used to fix anything against the walls and floors.

The only down side was that the surrounding earth would give warmth or make it cool in summer.

There are other methods, like digging around the house and pouring hard core, or poly on top the surrounding earth that diverts the rain water away from the walls.

The external work are the more long lasting. The internal stud walls makes the place nice.

[nog]

Thanks for the input (also Stuart and NT). Tanking sounds ideal, although I suspect it would be a bit ambitious in terms of cost when measured against the benefit - the area is really bonus space but it would be nice to be able to make better use of it. Next year, I qualify for the Staywarm energy tariff so I may look at plumbing a couple of small rads down there. That, together with a bit of air turbulence, may be enough.

[Pete C]

Hi,

Came across this which may be of help:

cheers, Pete.

[nog]

_Very_in-ter-est-ing_! Thanks Pete.