I have recently purchased a period property built in the late 1800s. My survey indicated that the basement of the property (being used as a dinning room) had not been properly tanked when it was converted for living use in 1980 but that there were no structural issues. When I had a damp specialist look at the basement they indicated the possibility of damp effecting the timber structure if I did not have the basement tanked properly. No damp effects the rest of the property only the basement. Given that the property has been in existence for some time, and that the conversion had been carried out some 25 years ago, is it now worthwhile undertaking such an expensive project? After all surely any damp would have effected the timbers, if it was going to, over the course of the last 25 or 100 years and shown up in the structural survey? Is the best way to deal with damp in basements to tank it or is there a better method? Any help please would be appreciated.
- Thread starter ABastow
- Start date
Does it seem damp? I would just live in for a year or 5 and see what you think then. Let the seasons change, see what happens when you live in it, see what the heating does...
If it does get damp, I would not see tanking as the first option more as the last.
If it does get damp, I would not see tanking as the first option more as the last.
Paul Hopper
Member
- Messages
- 98
- Location
- Leics/Notts/Derbys border
ABastow
If you follow the "specialist " route. be very careful, possibly Matt Green on this forum may be able to offer some advice as to who to use. whatever you do you must be certain that the "specialist " is exactly that.
A personal recommendation is always best.. and do not be afraid to pay for the examination of your walls. beware "freebies"
Paul
If you follow the "specialist " route. be very careful, possibly Matt Green on this forum may be able to offer some advice as to who to use. whatever you do you must be certain that the "specialist " is exactly that.
A personal recommendation is always best.. and do not be afraid to pay for the examination of your walls. beware "freebies"
Paul
Dampmeter readings dont read damp and are not appropriate means of diagnosing damp problems.
Tanking is not a good way to treat damp problems in period house cellars.
Given these points I would have some doubt about what youve been told.
I also suspect this might well be a case of no problem to solve. Are there signs of a damp problem? If not, as already said, live there for a bit and see if its ok or if any damp related problems crop up.
NT
Tanking is not a good way to treat damp problems in period house cellars.
Given these points I would have some doubt about what youve been told.
I also suspect this might well be a case of no problem to solve. Are there signs of a damp problem? If not, as already said, live there for a bit and see if its ok or if any damp related problems crop up.
NT
Matt Green
Member
- Messages
- 670
An invasive damp survey may not tell what you want to know. If someone were to drill through the tanking and take a sample from the masonry behind, its likely to be wet as the walls are earth-retaining. Whilst it might tell you HOW wet and that might effect the water-proofing specification, drilling through the tanking sort of defeats the object of having it.
As NT says, damp meters tell you that a surface has a low electrical resistance, not that they are necessarily wet.
Is the finish actually failling? Is the paint flaking? If not then the cause of the low resistance may well be condensation on the cold walls.
As for timber decay in the joist ends, the addition of a tanking to the inside surface of the basement will have changed the way ground water behind the walls moves into the building. If it can not evaporate through the walls it may move upwards and increase the moisture content of the joists ends if they have not been isolated from the masonry. Whilst it might possibly be a decay risk, at this point there are too many variables regarding the exact construction for me to do anything but guess about what might be happening (which is why I tend to leave these sort of posts alone).
Can you post up a few pictures and/or explain what happens at the point where the basement meets the ground floor above?
Hope that helps a bit- essentially I wouldn't touch the tanking unless there's an obvious problem and the joists ends might be an issue depending on the construction. It's long term stuff though, nothing to lose sleep over.
Matt Green
As NT says, damp meters tell you that a surface has a low electrical resistance, not that they are necessarily wet.
Is the finish actually failling? Is the paint flaking? If not then the cause of the low resistance may well be condensation on the cold walls.
As for timber decay in the joist ends, the addition of a tanking to the inside surface of the basement will have changed the way ground water behind the walls moves into the building. If it can not evaporate through the walls it may move upwards and increase the moisture content of the joists ends if they have not been isolated from the masonry. Whilst it might possibly be a decay risk, at this point there are too many variables regarding the exact construction for me to do anything but guess about what might be happening (which is why I tend to leave these sort of posts alone).
Can you post up a few pictures and/or explain what happens at the point where the basement meets the ground floor above?
Hope that helps a bit- essentially I wouldn't touch the tanking unless there's an obvious problem and the joists ends might be an issue depending on the construction. It's long term stuff though, nothing to lose sleep over.
Matt Green