I have double glazing windows throughout & have replastered the inside verticals of the window & the sill above the window. Howver the last window I have come to, I pulled the old blinds off, whereby a lot of crumbly plaster broke away. This exposed the underside of the lintel, going across the window on the internal brick wall (I presume) howver there is a a gap (4" wide) running across from left to right between the external wall & the lintel ? very odd. Im happy to wet plaster (bonding plaster) & skim over the linel to bring into line with the top angle bead, BUT I do not know how to fill this gap. It seems there were some kind of cement supports that have broken away. I was thinking of fixing wood across (fence post size) and screwing it into the lintel & outside wall then wet & skim over but Im not sure ? any ideas.
Sounds like you have exposed the cavity although 4" is rather wide for a cavity. Suggest you try form a cavity tray using a length of dpc, hold this in place with some insulation, tack a piece of expandmesh over the reveal and gap and use this as a base for re-plastering.
Thanks for your replies "stoney boy" & "Steve Bain"
I have included a crude diagram if this helps (as if looking up, from the inside), but get the jist of what you are saying. Again the gap is about 3-4" wide, and when I look up I can see the inside of the external brickwork. The lintel doesnt cross the gap far enough. Not sure how to cover, so i can wet & skim plaster over. I will need to drill 2/3 holes for vertical blinds but thats it really Hope the diagram loads up ok.
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