Damp under upstairs bay window

[hansPulesh]

Hi all,

the upstairs bay window has a large patch of damp under it. After investigation, I can see that the windows frame sills on the outside (which are made of wood) have been pulled apart and there is a gap between the frame sills at either sides of the bay and the one at the front of the bay.

The damp walls sits directly under these sills.

I had a builder come over yesterday and he said that it can't be fixed until it's a nice hot day - he said it's best to let it dry out and then to seal the gaps off with silicon sealer.

Is this the right thing to do? I'm worried with all the rain at the moment and would rather that the problem doesn't get worse? Does it have to be completely dry before the silicone can be applied?

 

[i_am_fubar]

2 things.

1) It is usual to have a gap between the window and the sill, especially with uPVC. This allows water that may get into the frame to drain out. Sealing it MAY cause more of a problem.

2) I would agree that you want to let it dry out before sealing (if that is the issue). Holes let water in and out and while it's open, leaving it open will assist with drying.

Where is this damp? in the wall, or floor. Top, middle or bottom?

I had some dormer windows with a pinhole in the lead flashing that was causing damp half way down the wall on the inside.

Fubar.

 

[hansPulesh]

2 things.

1) It is usual to have a gap between the window and the sill, especially with uPVC. This allows water that may get into the frame to drain out. Sealing it MAY cause more of a problem.

2) I would agree that you want to let it dry out before sealing (if that is the issue). Holes let water in and out and while it's open, leaving it open will assist with drying.

Where is this damp? in the wall, or floor. Top, middle or bottom?

I had some dormer windows with a pinhole in the lead flashing that was causing damp half way down the wall on the inside.

Fubar.

Hi, thanks for that.....

1) The windows are made up of a wooden frame on top on a wooden sill and then an aluminium window unit is placed inside the wooden frame. There are no upvc parts to the windows or frames.

As it's a bay window, the angles where the windows meet are where the wooden sills have pulled apart and this is where the gaps are.

The damp is under the windows at the angles where the windows meet in the bay. It is then spreading outwards. (On the inside of the bay walls).