Water under the ground floor joists Damp can be a major issue in the home. Find answers to questions or post your own here.

[RichD1]

We had to have a couple of ground floor joists replacing recently due to dry rot. Whilst the floor was up we could see that the oversite was damp and was covered in mud type material I guess from the original building work which was about 2" deep.

As the house has always suffered from condensation I thought that this damp layer was acting like a sponge and was not helping the situation so I decided to clear it all out.

Whilst doing this I found that to one side of the house the water had obviously been running through from the front of the house to the back. When I cleared the mud out I found that there was clear water trickling out of the brick foundations at the level of the concrete oversite.

I suspect that we have an underground water source as the area is called Radipole Spa.

Interestly all the brickwork above the wet oversite are dry which tends to indicate that they are above the water table.

My question is; how can I stop this and hopefully reducing the condensation?

BTW, we have had more air bricks added.

Richard

[stoneyboy]

Hi richd1
Water passing through your subterranean walls could wash away the mortar and you may end up with subsidence.
Whether you need to do something about this will depend on the severity - now we've had dry spell has the water stopped? If not I suggest you try your local building regulations department and see if they can advise.
Regards S

[RichD1]

Hi stoney, the water (and its clear so not drain water) is still pickling through thats why I think it is an underground water course. The three adjacent properties also have the same problem. We did think that a French drain along the front of the house and down the side would be the answer, but it is quite a job. So thats why I thought tanking the side of the property could be an answer especially as we have the floors up at the moment.

Richard

[stoneyboy]

Hi richd1
Internal tanking will be difficult on a wet wall.
Your French drain option would be better but you will still have to stop water permeating through the wall from the drain.
If you can establish the area of the source you may be able to create an easier drainage path.
Regards S

[Skoolz]

Hi RichD1,

I have an exactly similar issue to your but mine is more because I'm on a hill slope and my attached neighbours(semi) are on the higher ground. Their floor and DPC are about 1m + higher than my house meaning their ground water is flowing downhill against my party wall and seeping from few morter areas on the subfloor and also rising and pooling on subfloor where I cleared some soil that had been previously heaped to cover it. I want to screed to seal the subfloor area to stop pooling and also re-seal mortar the seeping party wall areas..

By the way, also doing the french drain thing on the outside side walls to help and divert some of this water so I'm very keen to hear how you proceeded with this, especially covering the subfloor?