Re Injecting using old damp proofing holes...possible?

[maltaron]

I am getting confused. Surely if you have cavity external walls there is a proper DPC already in the wall around 150mm below floor level, so there is no pint in injecting another. Also, you say that there is a 3ft void under the floor, if the DPC exists (as it should) then a foot of water under the boards would not make the wall damp. Its a total fallacy that anything below the DPC and air bricks must be dry. You have not told us the age of the house as this would confirm if a DPC should exist.

 

[loply]

Also, you say that there is a 3ft void under the floor, if the DPC exists (as it should) then a foot of water under the boards would not make the wall damp.

Not directly, but that water would evaporate, pass through the floor, and make the whole atmosphere inside the house humid. It'd be like a steam room in there.

The airborne humidity would then condense on the cold surfaces, ie walls and windows.

The damp proof company would then come in and say you've got damp walls, need to inject this special chemical into your bricks, etc etc

 

[maltaron]

Possibly. loply, but one house I lived in was permanently flooded under the boards due to the high water table, but we had no damp.

 

[loply]

Possibly. loply, but one house I lived in was permanently flooded under the boards due to the high water table, but we had no damp.

Interesting. You could have cut a hole in the floor and went fishing, like those ice-fishing guys in the arctic

 

[Elder92]

The house was built just before 1900.

I am struggling to locate the source of this damp, although the air bricks are fairly low to the ground level so it is possible that water could splash in. What would be the solution if this was the problem, as the air bricks must be needed for air circulation? French drains around the building edge?