Help with minor flooding / damp proof (with diagram)

[boroborn]

Hello

I live in a 200 year old cottage that is one of the central houses in a terrace of 4. During the bad storms in the summer we suffered a flood in two areas of our house. One of these areas was close to an external wall towards the rear of the house. We were in the process of getting a new conservatory and mentioned it to the builders. They then ensured that all of the conservatory and the area in between ours and the neighbours conservatory were sufficiently damp-proofed.

The second area was in the kitchen\dining room. The kitchen floor is the lowest point of the house (below garden level). It is a solid concrete floor and there are 2 steps up to the living room which also has a concrete floor and this is the same level as the garden. In the summer the kitchen flooded quite badly - we removed around 25 full buckets of water to contain the flood. It was however in only one corner of the kitchen. No other damp anywhere.

After the conservatory was finished we wanted to see if that had improved the problem. Cue the heavy rain this week and we found that both areas still had quite bad damp. Strangely though out of the 2 areas the living room was now considerably worse with a puddle forming. the kitchen area was now just showing damp.

I have included a basic mspaint diagram to hopefully help someone visualise the problem.

The red line indicated the dampproofing, this is also fairly deep as well.
the blue areas are the flooding \ damp.

Any advice on this issue would be a great help. We are in the process of redecorating \ renovating so now is the time to try and hopefully solve it.

 

[^woody^]

This flooding - is it water gushing in through the walls and doors or just dampness when it rains heavy?

Damp in the kitchen - which is an internal room and at lower level, would indicate to me that the problem is ground water coming up, rather than coming in from the external walls. So the damp proofing to the conservatory will not help this.

If you are in an area susceptible to high water tables or poor ground drainage, then the water under the house will not go away, and is probably still saturated with the summer rains, which the winter rains have only added to.

If the problem is water coming up, then the only options are to either try and drain the surrounding ground, or install damp-proof measures to the floors and walls.

You probably need the cause properly diagnosed by someone suitable, and then the remedies can be determined.

Is it possible that the insurance cover will pay for some preventative work, or even contribute to?

The neighbours must be experiencing something similar, so have they done anything?

 

[boroborn]

Thanks for the response woody.

In the summer I would say the water was gushing in the flood in the kitchen. To give you an idea how much - well I managed to contain it in the corner by sitting there and scooping the water into a bucket with a dust pan. If I stopped for 5 mins then it would have crept further into the room.
In the front room it saturated the carpet but was no where near the amount of the kitchen.

We claimed on the insurance and they classed it as storm damage, but I'm worried that if we redecorate and it happens again they won't pay out. I wouldn't blame them - especially if I haven't tried to sort the problem.

We are built on clay and after speaking to my neighbour he said the water table is very high. He has had problem in his back garden. He also claims to have rising damp in his front room (which backs onto ours) and in his kitchen (which backs onto ours). Their house was the original cottage - the other 3 were built at a later date. I don't know if this explains why we are have flooding problems as opposed to "just" damp?

You mentioned that we could drain the surrounding ground - how would we go about this? One company we have phones have said a sump - would this do it? We are going to arrange for a damp proofing specialist to come and view the problem. I always like to do a bit of research first though so thanks again.

 

[^woody^]

There are many methods to drain the ground, and it can be complex. It would involve thorough ground surveys to determine the various subsoil layers, and then devising a suitable drainage system to take the water away. It may not always be suitable or feasible, but it is a possible option.

A sump under the kitchen is one option, but needs investigation first to see if it is practical.

Be careful with damp treatment companies. They are a business, and many will provide a 'report' but for some strange reason, the conclusions tend to recommend their particular treatment as a solution to your problem.

Unless you are confident as to their impartiality, then get a few round to see if their opinions differ.

Or get a suitably qualified surveyor round, to give you an independent survey and opinion. But check experience first as a structural engineer may be better as he may know more about the ground conditions.