Damp At Back Of House - Expensive to Fix??

MartianMan

Note sure if this belongs in the property section; hoping there might be some DIY'ers or builders here who might know...

I recently had a look at a terraced house which is for sale, and apparently there is damp at the back of the house.

I didn't actually notice it myself, the auctioneer told me on the phone that it had been mentioned in a survey which someone had done. The sale was agreed, but the sale fell through because of this.

The damp is in the kitchen extension which looks as if it was built in the '70's. The back garden consists of a very steep hill which I expect runs the rain down to the kitchen.

Does anyone know if getting this type of problem is difficult and/or expensive; and what work would usually have to be done to solve the problem?

Borzoi

How long IS a piece of string?:D

You've two things to address, the source of the dampness and the results of it.

If as you suspect you've bad drainage in the garden, you might need to get diggers in to dig a decent trench and soak pit away from the house.

Then you can look at fixing the damage, but you won't really know the extent untill you've pulled off the damaged plaster/mortar,, to see what the structure is like.

Get a decent surveyor to look at it if you're thinking of proceding with this house.

MartianMan

Thanks Borzoi,

unfortunately it would be more or less impossible to get a digger in.

I suppose it's always possible that it's the result of something more simple, such as the damproof not having been put in properly (or at all).

Is it possible that damp could have rotted the actual blockwork of the kitchen extension even if it's maybe only 30 year old?

So if it was very bad, the kitchen could need pulled down?

If I ask a builder to come out and have a look at the house with me, would they usually be prepared to do this even though I do not own the house, and there's always the possibility that at the end of the day I won't either...?

Borzoi

Ah, the 70s, golden age of cowboy building in this country as it was in the happy land after genuine tradesman and before good building regulations.

the damproof not having been put in properly (or at all).

yes, it was the 70s

If the damp is that bad a builder might be able to have a good poke about (with the owners permission of course) and get to the nub of things

In short it's possible that the extension might need to be pulled down - bear in mind that someone else had a surveyor look, and they walked away. You would be wise to to, unless you can get a solid estimate of how much it would cost to get right - don't take the risk yourself

Sleipnir

I would get your own surveyor to take a look and ask whether he believes it is viable to have the repairs done, or would it be better financially to have it torn down and rebuilt.
Eitherway if you did decide to buy it you could ask that the seller to take into consideration the work that will have to be done and lower the price.

Victor

If you really want this house, spending €500-€1,000 on a surveyor (best), engineer (next best) or architect would be an investment worth making. Get the same person to check out the rest of the building also. The damp might be affecting skirtings, floorboards, and plaster - more than you might realize.

Being a terraced house, repairs will be more difficult and there may be obligations to neighbours.

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The block work should be sound, however the plaster would most likely have to be redone. The likely error was no vertical damp proofing (in pink on drawing) was done between the wall and the raised ground and water gradually came through.

Alternatively the slope of the ground has changed slightly and has risen above the damp proofing (red line on drawing).

Having a land drain (a typical drain pipe with tiny percolation holes, wrapped in a filter membrane) might have helped.

I would also question how structurally sound the wall retaining the ground is (the ground is pushing against the wall).

Damp can take quite some time to remove once it sets into a building (remember it has had up to 30 years to get there).

Depending on how long the section of wall is I'm guessing €5,000 to €20,000 to make good the damp proofing, plus the cost of repairing rotten timbers and damaged finishes. That is the minimum you should be taking off the normal price of the house.

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Beware of investing too much time in bidding for this house as it may have been sold already and they are merely looking for an agreed marker on how much should be taken off. Ask for the previous surveyors name and ask him (the suveyor) for a copy of this report (he has no legal responsibility to you otherwise).

Victor

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