Damp in floor ???

[marsaday]

Water feed is fine and not leaking.

Someone has given me another idea of what is going wrong - condensation.

All caused by the vent in the cupboard (was for boiler which has now been moved) - photo shows this in the first post i think.

He says the cold air is making the floor cold and so outside the cupboard the warm air is condensing on the floor and the wall.

so i have blocked up the vent and will see what happens for now. It is a waiting game i suppose.

 

[JohnD]

ventilation does not cause condensation.

Quite the reverse.

How did you establish there is not a tiny pinhole in a buried pipe?

You said the water was found under a floor covering
View media item 67283If this is impervious vinyl, how did the warm moist air reach the floor?

 

[marsaday]

Well i will see how the blocked vent works out and then i will look at the path which is possibly breaking the damp proof barrier, but i still cannot work out where it is. I cannot see any bitumen or slate . What would they have used on a 1930's build for this ?