Selling a House with Dampness

Ed_Zep

Hi,

I live in a 1930s semi-detached which as a few areas of damp.

I've read a lot about "rising damp", which apparently is incredibly rare, so I'm looking more holistically at other causes before selling my house.

The worst area is the kitchen/extension wall. Either side is a concrete floor. Also on the outside is a rendered wall. There are some small cracks but the damp seems far away from those.

Can concrete floors cause damp to move up through the wall?

I understand that they should have a damp proof membrane but what if the floor was put down without one? Could the edge of the wall be cut away and some membrane be put there? I'm trying to avoid taking up any tiles.

I'd be interested in hearing what other people did when they tried to sell a house when the report said "damp".

Thanks,
Ed.

go_cat

Make sure you price it accordingly to reflect the work required

robatwork

Most buyers will run a mile if it's got serious damp.

Most damp comes downwards so check walls and the roof above the evidence...and get it fixed

tbs624

OP - you mention rendered walls, so what condition is the rendering in? Any cracks? Has the rendering been taken right down to ground level or is there a bell drip edging?

You may want to consider getting an independent damp surveyor in prior to marketing the property - you can then decide whether you want to sort any recommended remedials prior to sale. Look under the Property Care Association.

You may also find it useful to read Jeff Howell's comments on damp, rising and otherwise ( google him) . He has a building background, lectures and writes books and newspaper columns on property issues.

Ed_Zep

tbs624 wrote: »

OP - you mention rendered walls, so what condition is the rendering in? Any cracks? Has the rendering been taken right down to ground level or is there a bell drip edging?

You may want to consider getting an independent damp surveyor in prior to marketing the property - you can then decide whether you want to sort any recommended remedials prior to sale. Look under the Property Care Association.

You may also find it useful to read Jeff Howell's comments on damp, rising and otherwise ( google him) . He has a building background, lectures and writes books and newspaper columns on property issues.

Thanks for that. I'd considered an independent damp survey but wasn't sure who to go to.

The rendering doesn't go to the ground and there seems to be some curve to it. It doesn't seem directly wet underneath.

This is a 1930s semi. I think the damp course is blue brick. The black paint on them I've noticed has come away in a spot which matches where the wall is wet.
The other bricks don't have that peeling paint.
Could the DPC have failed?
The wall inside is definitely damper after rain.

I'm in a quandary about DPCs. Some old buildings don't have them at all. Presumably the lime plaster/mortar means the water evaporates.

mrs_motivated

Just a thought, but has the property got cavity walls. Many years ago I bought a property with 'damp', and the previous owner had blocked up air bricks and installed extra radiators to try to deal with it. It made it worse , because it was condensation which had caused the damp.

I recognised this and knocked the plaster off, dry lined the walls and had them replastered. Ok this was a messy solution but cured the problem totally. This is quite a common in 1930's properties which were often plastered straight onto brick

nollag2006

Quickest and easiest way to address this is to Google "damp proof specialist" in your area and get a couple of them around to see how serious the problem is.

It might be quick and cheaper to address the issue, than you think.

abankerbutnotafatcat

We found someone on this site. The visit and resultant survey was extremely useful and we're currently putting the advice in to action!!!

http://www.property-care.org/

Johnhowell

nollag2006 wrote: »

Quickest and easiest way to address this is to Google "damp proof specialist" in your area and get a couple of them around to see how serious the problem is.

It might be quick and cheaper to address the issue, than you think.

Be careful with this - as they will probably send a salesman (they will call him a "surveyor").

OP a fully qualified Chatered Surveyor should be employed to investigate the source of the damp and advise on remediation measures.

Good luck.

tbs624

abankerbutnotafatcat wrote: »

We found someone on this site. The visit and resultant survey was extremely useful and we're currently putting the advice in to action!!!

http://www.property-care.org/

See post 4

nollag - as another poster has said, a "damp proof specialist" sought out via google or the yellow pages is likely to be one who has a vested interest in finding work to be done ( by using their very own DP "skills")& is not what the OP needs. The word "specialist" means nothing.

Independent damp surveyor is the best way forward - see notafatcat's link above.

AlexMac

You seem to pose 2 questions-
1.what do I do about selling a house with a bit of damp, and
2. has anyone experience of this; Yes, we've done 2- by waiting till the survey and simply adjusting the price a little (if and when) the buyer starts to haggle- but only in proportion to the problem; ie a few £k for damp remedials.ivoulos gripes).

But the bigger problem is that buyers might be sacred off and not even make offers, as only the best presented homes sell in a buyers market. So as well as doing all the usual stuff to make sure your house is really clean, de-cluttered, and staged (like in the tv property progs) let's look at whether you can Xremedy the damp-either by a proper job or at least, ameliorate or conceal it.

The causes of damp are straightforward and threefold; either
a) rising; groundwater coming up from faulty or absent damp courses or where earh is piled up against an external wall ( or through semi-basement walls if these have been poorly 'tanked' -ie waterproofed) or
b) penetrating; leaking from internal pipes, or externally from leaky roofs/slipped tiles/slates, broken gutters or downpipes, etc, or
c) condensation; from atmospheric moisture, water-vapour from cooking, showers, tumble-dryers (and humans!) aggravated by poor ventilation or inadequate heating- especially where damp condenses on cold internal surfaces (such as ocurr if you can't afford to leave the heating on all the time - and especially on external walls or in corners, or in a typical rear extension which may be colder because it has more external walls than the rest of the house (and which are maybe also less well insulated) or less heating or more cooking vapour...
and in some cases a combination of two or three.

And after a while, wall plaster which has been prone to rising or penetrating water can become hydroscopic (think I spelt that right?) and more prone to damp as salts from groundwater or old brickwork attract airbourne damp-

which is why the most thorough remedy is to identify then remove the cause of the damp, but then to also strip and repalce the cement render and internal plaster of the affected walls- which is a lot cheaper than it sounds- and unless you want a 25 year guarantee, to get a builder to do this rather than a more expensive 'timber and damp specialist'. But you can get away with much less work.
First check the bledin obvious; are you ventilating, are the gutters/downpipe leaking or is earth piled up externally? From your decription, its unlikely that water is coming in from outside via a few render cracks, (unless it's trickling in at the top from leaky gutters- go out in the rain and look). It's also unlikely that a house from the 30's would have no damp course at all (unlike all the 1900's houses I've owned), and while you might have a less-than-perfect damp membrane under the concrete floor this can only be checked by ripping up and relaying (which you won't be raaased to do) and in any case will not cause damp higher up on the walls (Your Q 'Can concrete floors cause damp to move up through the wall'? No).

So in terms of next steps- copy me; I've had both the pukka remedy done -(i) fix leaky gutters in upper rooms / or inject chemical DPcourse in ground-floor walls, strip walls back to brick, render and replaster to height of 1m- costing anything from a £few hundred to a few£k) and I've also
-(ii) DIY'd a superficial botch - I have few practical skills- I was a librarian for gods sake- but I've laid ceramic tiles on kitchen floors, tiled walls over minor damp in a cold bathroom, and stuck foil-backed plasterboard on slightly damp walls.
And if you redecorate, heat, ventilate and hope for the best, you'll probably get away with it as I did. .

And the worst that happens is you get a savvy surveyor and have to knock a few quid off the price. Good luck!