Damp around windows

[josejaspy]

We were recently stripping wallpaper in our house (built in the 1950s) and uncovered a long strip of damp plaster along the insides of the window frame which crumbled away as soon as we took the paper off.

The house is brick with a cavity wall, but the windows appear to be mounted on single blocks (they look like long breeze blocks to be honest) which run the entire window height, with a concrete lintel above. The cavity opening has just been plastered over and I'm not sure what the wavy barrier is in the cavity - perhaps a DPC? The exterior wall is rendered.

After reading some posts on here, I replaced the sealant along the exterior side of the window frame and filled in the gaps around the window with expanding foam, but with the cold weather lately the damp has reappeared.

My questions...

1. Are the windows meant to have been fitted that far forward? As in, why have they left so much space (~5 cm) between the frame and the cavity, or is that normal practice?
2. Is there anything I can do short of refitting the windows to stop the damp coming back?
3. Is it worth running a bead of silicone along the interior side of the frame or is that pointless because the real issue is thermal bridging?

Thanks all - we have a baby on the way and this will be the nursery so keen to get it right.

 

[noseall]

1. Are the windows meant to have been fitted that far forward?

It looks as though the external masonry is still visible on the warm/dry side of the window, so this is a no-no. It will inevitably lead to either cold bridging or damp wicking through, if this is the case. Window fitters are always trying fit their windows in the optimum fixing position rather than the best thermal/damp resistant position.

 

[josejaspy]

Thanks noseall, you're right. It is the same masonry spanning the window frame.

Do you think there's anything we could to resolve it short of refitting the window? We were thinking perhaps a strip of insulated plasterboard with vapour barrier along the affected areas might do the trick?

 

[noseall]

Thanks noseall, you're right. It is the same masonry spanning the window frame.

Do you think there's anything we could to resolve it short of refitting the window? We were thinking perhaps a strip of insulated plasterboard with vapour barrier along the affected areas might do the trick?

We tend to make clever use of DPC and are careful where we place the board adhesive when dealing with troublesome reveals. If you have the room, insulation is a good thing on the reveals - yes.