Rising damp advice please

dybleah · 30 Mar 2009

Hi!

I have a small building in my garden that was built, unfortunately, by some rubbish builders. It currently has a few problems... The one I'd like to ask about is the fact that there is often mould and damp on the walls.

I realise the best way is probably just to knock it down and do it again, but as things stand, can someone please advise me as to how best to damp-proof the walls? I'm a beginner at this, but would at least like to know the steps and the recommended paints/sealants to use.

THANKS VERY MUCH!!

^woody^ · 30 Mar 2009

You will have to explain what the construction is, but it sounds like condensation which may be on its own, or in addition to any penetrating damp.

dybleah · 31 Mar 2009

Thanks woody for your reply - I think I saw you on another topic regarding damp!

I will add more details later this evening perhaps and I'll attach a few pictures to give you an idea.

ColJack · 31 Mar 2009

someone told me that rising damp is a myth..
it's actually penetrating damp from outside or condensation down the cavity...

for "proof" he said, get a brick and stand one end in a bucket of water and see if the top of the brick is wet after a few days..

^woody^ · 31 Mar 2009

That would have been softhead who told you that.

Do you think it matters if the brick has no mortar around it? Does it matter what clay the brick is made of, or how it was fired? Does it matter if it is solid or has a frog?

Should we include blocks in this little experiment?

Is the water in this bucket under any pressure? What about salts, do they affect anything?

Shall I tell the next BCO I meet that we wont be bothering with a DPC or DPM in future?

Think of all the factory closures and redundancies from the DPC manufacturers. Oh, the nightmare

dybleah · 1 Apr 2009

OK I have more pics and info

Basically, I'm not too sure of the foundations and stuff, but another person built this little house that's in the garden. Its got brick walls (double layer?) and its sitting on what I assume to be inadequate amounts of foundation. Apparently it was a very shabby job - hence the damp and bad condition of the walls.

I've also included what I've been told to be the "standard" solution to this: get rid of mould, put a sealant layer and then plaster it and then paint.

I realise that this wall/building is probably not gonna last for years and years but I would like to know the best solution for the walls, short of tearing it all down.

So take a look and someone please:
1) jot down some steps to take to best rectify this and
2) tell me whether I should keep/return this B+Q stuff (or better alternatives)

THANKS AGAIN

View media item 10096 View media item 10097 View media item 10098

^woody^ · 1 Apr 2009

It is hard to tell, but it does look like a penetrating or rising moisture problem rather than solely condensation.

Soft rotten or damp skirting will be indicative of rising or penetrating damp issue. In which case , sealing it with that product wont help - the damp will just go around it.

You have to identify the cause of the damp first, before you can determine the remedy

Have you checked externally for signs of dampness which would be getting through?

dybleah · 1 Apr 2009

Ummm how do I do a systematic search for all these causes of dampness??

I'm completely new to all this! Thanks for the aid

^woody^ · 1 Apr 2009

You will have to search this forum or google for information as to the common causes of dampness, and the signs which each may exhibit.

I don't really want to re-write it. Its fairly common sense really.

Or you may wan to let a suitable person have a look and advise

But to get you going, check the condition of the external wall - pointing and brickwork and for leaking gutters etc.

Check no ground is above, or within 150mm of any DPC.

If this area of wall externally looks darker than surrounding wall, then its damper, and so find out why

dybleah · 2 Apr 2009

after some reading, it sounds like I might have to use salt neutralisers? The plaster might be getting wet from beneath if its touching a DPC...

But this wall is so shabbily done, i dont even think they put a DPC in.

diynot

If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.

Select the supplier or trade you require, enter your location to begin your search.

Are you a trade or supplier? You can create your listing free at DIYnot Local

Rising damp advice please

Similar threads