Various damp problems with solid walls...

Jazzking

Hi there, I have acouple of damp related questions which I'm hoping some of you experts might be able to help with.

Fisrt of all, the house is an early 1800's end terrace with 400-600mm solid stone walls, rendered (slightly damaged) on the outside and on a slope, so the back of the house (kitchen) is actually about 1m below street level. The house does not have a damp proof course, as far as I'm aware.

1. We are experiencing damp in the kitchen in the "underground" bit of the house, both through the floor (salty deposits coming up through the orignal quarry tiles) and similar salty deposits and flakey paint on the walls under the pavement. What can be done to prevent the damp coming in since we're below ground level, an injection DPC surely wouldn't work from the inside and nothing would be achieved by putting a chemical DPC in from the outside above the pavement which is about 1/3 of the way up the wall!
TO solve the problem with the floor, am I right in thinking we can just put a waterproof membrane over the top of the quarry tiles and put self-levelling conctrete over the membrane, or would the tiles need to be dug up first before putting the membrane down?

2. The gable end of the house, including the chimney stack and also some areas of the front of the house has some quite large cracks in the render; this results in the inside walls (both ground and first floor) becoming damp and peeling in wet weather.
Short of re-rendering the whole house (quoted £3500 to do this) what would you suggest can be done to stop the penetrative damp - try and repair the render on the outside somehow, or put some kind of non-permiable paint on the inside and repaint on top? Not sure how long the render has been up, but we live near the sea which might affect things...

3. Finally(!) we have a small cellar, which unsurprisingly is damp also and one of the joists under the floor at the front of the house has damp rot. After replacing the joist would introducing some ventilation into the cellar by putting a extractor/recirirculating fans in the wall up to the pavement be sufficient in your opinion or would the only real solution be to tank the cellar by putting a waterproof sealant/membrant on the floor ad up the walls as well? We are currently experiencing damp coming through the slabs on the floor when the dehumidifier is left off so I'm guessing that both ventilation and tanking would have to take place in order to stop the damp.

We've had two guys come round already, one says to solve the damp in the main part of the house, just re-render as it's probably penetrative damp through the cracks in the render. The other suggested taking off the plaster in the downstairs and putting a DPC in, but I'm struggling to see how this will help with the underground, but of the house and also the fact we have solid walls, isn't that a problem?

Sorry for the long post, but I'm looking forwrad to hearing some of your suggestions as to what sounds like the best plan of action!

Many thanks,
Alex

ajbaker

Since you have a very old house, I would be more inclined to be sympathetic to the way the building 'used' to work rather than use modern materials/methods to keep the damp out. Having said that, I am NOT an expert and am struggling to learn things as I go along as an owner of a listed early 1800s proprty myself.

Without a doubt, the wall render and plaster would have originally been lime based which would have allowed the walls to 'breathe', effectively controlling the damp without damp proof courses etc. Expect to pay a lot more for lime based renders and plasters.

Installation of any damp proof courses will prevent damp from rising but it will not cure the problem - it will simply make the brick below the DPC very wet!

As for the cellar, yes it should be ventilated. This again should control the damp problem.

Finally the kitchen floor - I believe a modern waterproof membrane is recommended for tiled floors in period properties. Personally I would hate to see an original quarry stone floor covered so would raise the tiles, put the membrane down and then relay the tiles. However this is personal preference.

As I said, I am not an expert. However I do know damp 'experts' for modern houses are also clueless when it comes to period properties. If they run when you mention lime, that's a good clue! You will get much better and more informed advice over at the period property web site, which includes info on people who really are experts in this area.

Doing things 'right' will be more expensive, but I think this is the cost of the privilege of living in an old house. Please let me know how you get on.

Jazzking

Hi, thanks for taking the time to respond, and for the link to the period property website - I shall have a look at that in details over the weekend.

Interesting what you said about the render, I'm curious as to what's underneath the render on the outside, and if it would survive without any render on at all, or would we still get damp due to the fact there's no cavity for any moisture to run down?

Looking into ventilating the cellar; just need to see what the council say about us doing it as it fronts onto the street....

I agree that it would be lovely to keep the original quarry tiles in the kitchen, however they are fairly well worn with chips out of them etc. The OH is after a fitted kitchen, whereas I like the standalone units and the floor that we've got (despite it looking old!) but would like to control the damp...

Thanks again, if anyone else has anything that might help or suggestions then I wold be very grateful.

Alex

ajbaker

Private message sent, Jazzking.