To replace concrete floor or not..?

[electrician]

Property built on a slope age 1870 two rooms are built against retaining wall then there is hallway I have noticed it always smells damp I took the plunge and dug up a section of the floor in the hallway and found its 2 “ concrete then soil the brick wall below the concrete is damp there is no dpc in the brick work in the floor in the hall there is no salt etc sometimes the edges are which has a little trough has water in it should I dig it all up put put down hardcore, sand, insulation, DPM, concrete and screed or leave as is Alos is there any good product to inject, put into the brick work that works well, I see many product that appear to be paint on solutions but its hard to tell if there any good or just sales hype anyone had or done anything similar would appreciate views many thanks.

 

[MatthewC]

Hi there electrician, welcome.

I'll bump this back up to the top as first posts take a while to appear. You will find that there will be many requests for more information, especially photos.

There is lots of information here if you search the forum as this sort of question has been answered many times before, but in general it's a NO to a DPC and a NO to any injection. If you have rooms built against a wall which retains higher ground then it is bound to be damp; sorting that source of the dampness should be your first target rather than addressing the symptoms. I have been able to lower the ground outside my house and it is now completely dry, with no DPC, no membrane, no injections.

I'll let others have their say...

Matthew

 

[Penners]

Welcome to the forum, Electrician.

If the wall of your hallway has a high soil level leaning against it outside, then I fear that dampness is going to be quite difficult to eliminate. Sealing it inside will only serve to trap the damp within the wall, and ithe sealant is likely to fail quite quickly. Insertion of a damp-proof course below the exterior soil level will be pointless.

Do you own the land "uphill" from that wall of the house? If so, then your best plan of action would be to try and dig out an air-gap trench between the soil and the house wall. I presume that this would mean constructing an additional retaining wall a little way away from the house wall.

As an alternative, if you don't want to build this additional wall, you could dig down to below the internal floor level and insert a corrugated plastic sheet material against the wall (there's a special product for this, but I can't remember its name - I hope someone else will!). You then backfill against this sheet material. The impermeable plastic keeps the damp soil away from the wall and the corrugations allow the wall to breathe.

If either of these suggestions sounds practicable, do post back. People on this forum who have carried out similar projects can then give you more detailed advice.

 

[TheForge]

As an alternative, if you don't want to build this additional wall, you could dig down to below the internal floor level and insert a corrugated plastic sheet material against the wall (there's a special product for this, but I can't remember its name - I hope someone else will!). You then backfill against this sheet material. The impermeable plastic keeps the damp soil away from the wall and the corrugations allow the wall to breathe.

Newtonite is one such material - we've removed acres from our house where it had been applied inappropriately.

 

[Penners]

That's the stuff! Thanks TheForge.

Would you not recommend it, then? I only know it by reputation, which seems to indicate that - used properly - it can be helpful.

 

[electrician]

Yes I though of sealing it but then it only go somewhere else
Don’t own the land uphill unfortunately? part of the hallway does have that method used sort of rat run between wall and room the other parts do not parts of the internal walls had a very similar method left on them but was sort of a bitumen corrugate but don’t know it worked very well