Damp entering under back door sill Damp can be a major issue in the home. Find answers to questions or post your own here.

[meldrew21]

Hi there. I'd be grateful for advice on best building practice for brickwork under french doors/patio doors.

Lifting my carpet shows damp penetrating to the extent that the concrete screed and base layer are both crumbling. The screed hasn't been protected because the polythene membrane isn't good enough.

Looking from outside the sill sits on one row of plain bricks. This row is lined on the inside by softwood to support the sill at the back. The wood is very wet.

Does there need to be some air circulation to avoid the build up of damp? If so how is this achieved?

Many thanks in advance.

[stoneyboy]

meldrew21,
There needs to be a vertical DPM behind the bricks below the cill.
end

[meldrew21]

Thanks for that, stoneyboy.