Anyone know about damp proofing?

[taybert]

We live in a solid walled house, probably about 100 years old. Off the kitchen is a small pantry which is below ground level, just a couple of steps to get in, under the stairs. We knew it was a bit damp but we've had bigger fish to fry so haven't really done much with it. Well, nothing in fact! This weekend I've cleared it out to make space due to another's project we're doing and we've been found it's all a bit worse than we thought. The skirting was rotten so we pulled it off. Behind the plaster was just soaked and the floor was wet under the vinyl. Today it's dried out a bit but there is clearly damp coming in between the wall and the floor and possibly through the walls and floor too.

Does anyone know how's best to tackle it? It's only a small, under stairs area so we don't really want to be messing around with pumps and stuff. I've looked a thing the cementaceous products which I think would be best. Is it likely our usual builder can do it or does it need someone special? Any tips on how to remove paint from a concrete floor to prepare to apply the product?!

Aaaaargh! It's always the same in this place, we can never do just one project, it always leads to another, and another......

I'm no expert but we had trouble with damp in a similar aged house. One thing that I was told (and seems to be working) is to NOT get cavity wall insulation...
I don't know if that's relevant but there you go...

No cavities! Just massive thick walls...

Yes, we have a Victorian house with thick walls and one damp room. We got a damp course put in - not altogether successfully - but it was a ground floor. Not quite sure how it wotld work on a below ground level room.

Are you sure it's damp and not a leak?

Yeah, pretty sure it's damp. The whole house is damp, solid limestone houses tend to be but we've knocked off loads of dodgy render and now it "breathes" a bit better so most of it is fine most of the time. This is different though, as the ground level outside is above the floor inside. I think the main problem is the join between the wall and the floor. The skirting was sitting on top of it so I think it's just been sitting there soaking it up.

Hmm. I love a bit of damp over a bank holiday weekend!

It needs tanking - like a basement extension. You need to consult a builder who has experience of constructing basements. My mother had similar problems with a cellar and this will be the only way out because I assume you cannot alter the ground level outside. You could ask a surveyor for advice if you cannot find a builder with relevant experience.

So basically it's penetrating damp. Solid wall houses only work by drying out quicker then they absorb water.
In normal circumstances that happens fine, but there are almost limitless things you can do to fall foul of penetrating damp.
In your case, the damp ground outside will not be letting it dry ever.
The simplest and correct solution is to avoid all damp proof course "surveyor" salesmen, then lower the ground levels around your house, ideally 2 brick courses below the damp proof course, buy certainly below it. Then wait for things to dry out.
Good luck!

This is a pantry, not a cellar? When it was built it probably didn't have a wet floor.

You need to find where the water is coming from and fix it.

Common sources are:

-leaking pipe (pipes usually leak when they are 50-100 years old)
-raised ground level or paving which is above the height when the house was built
-Leaking gutter or drain outside

I will surmise that this area has a solid floor, possibly tiled or granolithic, and the other rooms have wooden floors. Is that right? It would be interesting to lift a floorboard in the other rooms and see if there is similar wet underneath.

Have you got a water meter?

As a stone house about 100 years old it probably does not have a d
p c. It could have a layer of slate but these are rarely good enough to do the job and don't stop water coming up through the floor. Of course there could be leaking water from drains and pipes and this should be investigated. You probably cannot dig out the ground all around this part of the house but if you can it may well help, but proper professional advice on your particular circumstances is vital.

It's a funny house, it's been messed around with quite a bit, it started as a house then was converted to a shop then back again. I was wondering today if the pantry with the lower ground level is even original, but there is a window in there and from the outside it matches the rest so I guess it is. The adjacent room used to be the shop and has a newer concrete floor but the other room has a wooden floor. I suspect it's just ground level outside. The levels may well have changed as there's been a garage extension on that side and I think it probably sloped down from back to front to start with. There isn't much we can do about that though. I don't think its a leak, there are visible pipes and they're all fine, pipework upstairs has all been looked at recently. No water meter. No mains gas. Plenty of "character"!

Yeah, we can't dig it out, there's a garage on the same level now so it wouldn't work. That's probably where the problem has arisen thinking about it.

If you are sure there are no drainage pipes which can leak under that part of the house or just outside, you are probably left with the the ground being too high. When you think about it though, it is possible to get professional advice regarding what to do. You obviously need less water in this location so ground drainage could help. Tanking as I suggested earlier should be a solution provided the excess water is diverted into drains and does not infiltrate the floor and walls.

Is the garage yours? Is that damp?

I don't think there is a cheap solution. Could you extend this area and make it bigger so employing modern building methods? Would it be useful to do that? Sounds a very interesting property !

So it's been drying for a couple of days now and this is what it looks like. To start with the wall was damp up to the top of where the skirting was (deep skirting, you can see the marks on the plaster). Now it's just at the bottom there where the floor and wall meet. It's like that along the length of the outside wall. There are pipes on the other side of the doorway but they're all fine. The bathroom is above there, we did have a problem with a leak from there when we first moved in but have had a whole new bathroom (new pipes, floor, everything) and its been fine since, there's no wet behind the bath or anything.

The garage is ours but it's a pretty crap structure leaning against the house, the floor level in there is above the outside ground. It's not any damper in there than anywhere else! There would be potential to extend to the side, in which case we'd probably bring the floor level in the pantry up to the kitchen. But that's not something we're doing any time soon, if ever. I can't imagine the hassle of an extension!

if there is a leaking water pipe or drain, it would be in the ground under the floor so you wouldn't see it.

I don't think there should be a mains pipe or drain there based on where the other pipes and drains are but then there are a lot of things about this house that don't make much sense. I guess the only thing is to dig and see? That'll be a massive pain in the arse! (But if that's what we have to do then that's fine, the last think I want to do is spend a load of money damp proofing it then end up spending more when it isn't right).

the drains in a house that age should be visible, there is probably a (cracked) clay yard gulley outside there the kitchen sink used to be, and an iron soil pipe running down from the bathroom into a (cracked) rest bend under the ground. Both may run into inspection chambers "manholes" which may have been hidden with earth or paving.

The water pipe was probably lead and is likely to be leaking under the floor by now, it probably ran in a fairly straight line from where the outside stopcock used to be, beside the front gate, to the corner of the kitchen near where the sink used to be. If the kitchen floor is concrete, patches of damp may be visible under furniture or impervious flooring.

If you know some with young, sharp ears, they might be able to detect a change in background noise if they stand around the kitchen at night while you turn the outside stopcock on and off. The hiss of a leak is almost inaudible, until it is turned on and off. Plumbers can detect leaks with a glass of water.

These leaks are common sources of damp in and around kitchens.

We don't even really know which was the front of the house originally (though it was probably as it is now), there are external doors on three of the four sides! The plumber tried to find the outdoor stop tap last year but couldn't, that reminds me actually, he was going to speak to the water company and find out but he's never told me if he did.

I just had a bit of a dig outside. There's some kind of solid paving about 18cm below the current exterior ground level (though most of the difference is made up with gravel). It still gives about 10cm of the internal wall which is below that level though. The drains seem to go in the opposite direction as I thought.

Is it very unlikely just to be an issue with the ground level pigletjohn? The plumber is coming for the other job so I'll see what he thinks. It'll be a problem if it's a pipe under the floor.....

I think you just have to plough through the possibilities one by one. How does the water get collected off the garage roof?

If there is a failed pipe under the floor it just has to be dealt with. Houses don't last forever! It sounds as if various owners have made numerous changes to the house down the years and you cannot assume everything has been done to a high standard or with the best materials. People bodge work and you can end up with the consequences. I do think if the plumber has no ideas, and I wouldn't be convinced they would, I would still contact a surveyor.

Well yes, in fact I tend to assume that everything has been done to a terrible standard with the lowest quality materials having done quite a few projects in this house and found this to be the case. The last owners seemed to have great faith in the powers of silicone sealant and used it for a variety of imaginative uses.

Water from the garage is taken down a down pipe to a drain at the front, the pantry is to the rear of the garage. I had a look whilst it was raining today and the gutters all seem to be working well.

I'm trying to figure out if it's likely that there is a pipe under there. Finding out the location of the exterior stopcock would be a start.

have a look at the pavement along the road, especially if there are other houses of similar age. Some of them will have had water meters fitted recently, and probably a newish cover about six inches square made of black plastic.

A few houses may still have their outside stopcocks accessible.

these will both give clue to how your house is likely to have been connected.

It is rare to have the waterpipe run along the backs of terraces of houses, or in a service alley, but it depends on local practice.

If the plumber has been around a few years. he'll know how to detect some leaks with a glass of water.

Leaking drains often have a smell of old soap, leaking pipes are pure and fresh.

I might be leading you up the garden path, but if it turns out to be supply pipe, it is not complicated to dig a new trench. It does not have to follow the same route as the old one. It also brings the advantage that a modern plastic pipe can be much bigger, and give improved flow for powerful showers using a combi boiler or unvented cylinder.

Unfortunately it's a village with a jumble of housing, no pavements, all a bit higgledy piggledy so no easy comparison. Our mains pressure is already really good so it may have already been upgraded. We'll look in to it anyway. Thanks for the info!