Anybody know about damp proof courses, or damp in general?

[BigBoobiedBertha]

Can a damp proof course fail?

I have just had a light bulb moment. I keep noticing damp on the lower walls of our house and it occurred to me today that it actually runs right the way round the outside of our house just above the skirting boards and I assume, roughly where the damp proof course would be. The house isn't that old (mid 1980's) but not very well built and I am wondering what is up.

Any ideas or advice please?

Has anyone added a path or patio or driveway around the house? Have the ground levels changed?

No nothing like that. The only thing that has happened is that a row of leylandii were taken down about 18 mthsago but wouldn't affect the far side of the house(it is detached) nor the back.

I've just been reading a damp survey that was done for our house 10 years ago. It says that damp proof courses are only as good as the company that installed them and yes they absolutely can fail.

If it's a badly built newish house it seems very likely it wasn't done properly. Do you have a guarantee for it? If not, I would think your best bet is to get a surveyor in to look at it and diagnose the problem - this cost us £300 in 2004 but it could save you a lot long term.

That is what I was afraid of. This could be expensive.

We have had all sorts of problems with plumbing and drainage, as have the other 7 houses in the cul-de-sac. Drain cleaning companies are a regular visitors around here and apparently they haven't be laid properly.

The other thing that might be the problem is that we have cavity wall insulation which we didn't know about until we got somebody to come round to quote on doing it for us. I wonder if that has been properly? I was reading online about how the damp could be the result of having something in the cavity wall. I don't really understand it so I might be putting 2 + 2 together and coming up with 5.

We have been there nearly 10 years though - it is strange this is getting worse now.

I don't know an awful lot about it but it does seem possible that cavity wall insulation is causing damp if it means the moisture from inside (breathing, cooking etc) is stopped from getting out properly and condensing instead. I'm not sure why it would be only low down, but that's something a damp expert would be able to tell.
Have any of the other houses got similar problems?

We thought we had a damp problem on an internal wall in a previous house. It seems the plasterer bridged the damp course by a couple of cm, I panicked when the skirting became rotten, luckily an honest damp contractor guessed, we removed the skirting board neatness up the plaster and hey presto no damp.

It certainly sounds as if you have a problem with the drainage being laid incorrectly.

A modern house should have a plastic dpc in the wall about 9 inches above ground level. It will not fail. Look at your walls, it will be a thin black line in the mortar joint. Where is it in relation to ground level?

Go outside on a rainy day. Do the gutters above spill?

Look at the bricks. Are they damp or limey below or above the dpc?

Is this wet in all rooms or some? Is it at a standard level or does it rise up in a curve or point?

Is it in a room with a solid concrete floor? Is it in the kitchen? Have you got a water Meter? Is the damp patch close to a radiator or other pipe?

Wow that is a lot of questions, Piglet John! I shall try and answer them concisely if I can!

The DPC is not even all the way round the house. I suppose the plot slopes a tiny bit, enough for a small step in the back garden, and it is lower at the front than the back. I wouldn't have thought it was 9" above the ground there - more like one bricks worth.

I had wondered about the gutters. We had them cleaned about a month ago because one of the down pipes became disjointed so that was fixed and the rest of it cleaned. Funnily enough, although the broken downpipe caused mould in DS1's bedroom, the ground floor in that corner of the house isn't mouldy. Probably the only corner that isn't actually. The sides of the house, where there are no gutters are affected the worst though.

The neighbours have been having their gutters replaced in the last couple of years. I think we might need to do the same. The builder guy who cleared out the gutters said that they weren't fitted properly - they are lower in the middle than the ends so water in bad weather will pool there - I should think in the current weather conditions have tested this but the damp patches predate the bad weather. I started noticing most of them in the summer and some are much older than that.

The damp runs about 30cm up from the skirting boards round the rooms. There are places where it hasn't taken hold but it is spreading. It is in all the downstairs rooms except the little study but there is only about 6.5ft of exterior wall there. It is a very small room.

I don't know if the other neighbours have the same problem. I haven't really asked them.

Yes we have a water meter - I think it was fitted last year. And yes we have mould is in a room with a solid floor - they are all concrete. I noticed it first at the back of the kitchen cupboards a few years ago but didn't really do anything about it. I assumed that it was poor ventilation between the wall and the cupboard and maybe somebody had split a drink in there because that is where we keep that sort of thing. Also, we had had a leak under the floor which we never found which ruined one panel of our newly refitted kitchen on the other side of the room but strangely, everything apparently dried out. I suppose it could all stem back to that. I know water can take a long time to come out but would it be years?!

Oh and mysteriously a whole new damp patch has appeared in the master bedroom in the last couple of weeks. I suspect that it is caused by the weather and an old and dodgy fascia board. There is a downpipe just there too. I don't suppose they are connected but who knows?

I think that about covers it. I reckon at the very least we need new guttering but could that be causing the problem all the way round the house?

"The DPC is not even all the way round the house"

I bet it is. I'd wager 50p that you just can't see it, possibly because the final ground level is not the same as the bricklayer expected. If you follow it all the way round, does it look as if it might be below current ground level? Do you have a flowerbed you could dig into, or is it concreted?

Turn off all the taps in the house and go and look at your water meter with a torch. There is probably a tiny air bubble in the middle. Does it ever stop, or is it constantly turning?

Sorry, it was dark when I read your reply so I couldn't really see to answer your questions.

No I can see all the DPC but in some places it is lower than others because of the level of the ground around it. I don't have to dig down or anything - there are no flower beds up against the wall that aren't level with the ground around it iyswim.

The brick work above the DPC is green. It is less so below the DPC.

I would look at the water meter but I am not entirely sure which is ours. There are two side by side, both on the pavement rather than somebody's garden. DH might know better - he has been out to look at it.

"The brick work above the DPC is green. It is less so below the DPC."

This suggests that the source of water is not from the ground (below the DPC) but from the house.

I am thinking of a water leak probably from a pipe in the floor.

If you can find which is your water meter, it will become clearer. Have you had a water bill since the meter went in, or, do you know the start reading (probably zero) and date?