dampness

[sad old git]

Hi All. I posted this question a while ago but can't remember what kind of response I got so asking for advice again. We have what looks like rising damp at the rear of our house( 100 year old terraced) and were directed to an ad by a company called Holland Damp Proofing. The work can be done on the exterior walls thus avoiding interior replasterng etc. If anyone has heard of or had any experience with this company I would be extremely grateful for your comments. There are a lot of cowboys out there.

[The Builder]

I don't know this Company, SOG, so I can't answer your question. There are plenty of good firms out there offering this sort of remedial service. There are also a lot of chancers, employing "surveyors" to advise ....... beware.

1 A great deal of "damp" is, in fact, condensation, where different solutions are needed.
2 If they're drilling from outside, I guess it's chemical damp-proof course injection. Depending on the construction of the wall, it can be very successful. In other cases it can be an utter waste of money.
3 As for avoiding interior plastering ........... if it is rising, then the plaster is already contaminated with various salts that will continue to show.

I'd really like to know what the wall is made of; how thick; how old; which room; also, is the outside ground level higher than the inside?

100 years old...... I guess it's 9" solid brick construction.

[maclarencat]

I think this is some sort of brick thingy that they install (not chemical ) if I remember correctly. I know we thought we had a damp problem amd they came out to give an estimate and very honestly told us we didnt need it as we had no damp. I think it is just an air circulation system.

[The Builder]

Oh yes, I know the one Mac. It uses ceramic tubes to "wick" the water out of the masonry.
It's another of those systems that can work .......... in the right situation, but, as you say, you don't always need it despite what the "surveyor" tells you.

[sad old git]

Thank you both for your help....Builder to answer your questions it is a back room looking onto a back yard and facing West and so not getting much sunshine at all.Looking at the depth of the brickwork I think it is a cavity wall and the outside ground level looks to be lower than than the inside. I hope this helps. Thanks again.

[The Builder]

There were some cavity walls a 100 years ago. Very few though. If it is, then there's nothing of any consequence that can be done from outside, since the work would only be on the outer leaf.

Facing West; back room; little sunshine .............. I would put money on this being a solid wall suffering from "penetrating damp". Brick built terraces are very prone to this. Rainwater will easily get through a 9" or even an 11" solid wall (which is why we have cavities today).

Once a wall is damp from rain penetration, it becomes considerably colder. This "chill" effect then presents a cold surface for any water vapour in the room condense on.
There you can have a classic case of rainwater plus condensation........ and quite possibly NO rising at all.

Before you settle on any remedial work, I would have an appraisal made by either an old-fashioned, experienced tradesman, or a Surveyor. It's essential to identify the problem first :o)

[sad old git]

Builder. Many thanks for your help.As you suggest we will get someone in to look at the problem and take it from there. I'll try to keep you updated as things progress. Thanks once more.

[wendylottie]

i had this company do this to my last house it didnt help us at all and was expensive so then i went down the cavity wall insulation route and also got a government grant to do it brilliant no more damp on the bottom of the walls and under windows and no more decorating whitch had become a yearly thing

[sad old git]

Re Dampness. To update all you helpfull AB'rs. We requested a visit for a consultant from Holland Damp Proofing and when he arrived and had a good look at our problem he said that his system would not work for us and suggested that maybe we should check for seepidge from a cracked drain or something similar. I was pleasantly surprised that he didn't try to sell us anything and actually gave us some advice so we are still investigating.