French doors fitted - cover / skim the cavity

[Locoblade]

Hi All

We've recently had french doors fitted into what was a window opening of the same width and I'm doing the making good on the inside. From the old window cill upwards there's virtually nothing to do as the old plaster is intact, but the wall cut down to ground level has obviously left an open cavity to the door recess which I need to cover and skim to match the top half.

The trouble is I haven't got much depth to play with relative to the existing plaster level, varying between about 10 and 20mm, so fitting in 9.5mm plasterboard and a skim will be very tight, if not impossible.

If the rest of the house was still a building site I'd cut another 10mm off the inner cavity with the disc cutter to give me more depth, but wifey says thats not an option so once Ive plugged the gap (fitted a cavity closer?) it would seem I can either...

*Knock the upper half plaster back to bare block and re-do the whole lot. Not keen.

*Plaster to a depth of 10-15mm staight over top. Can cavity closers be plastered over, and if not could I fill the cavity with foam instead? Also 15mm seems a bit thick for solid plaster?

*Try and find a thinner alternative to plasterboard to fix then skim over, which if I can manage it, seems to be the easiest option. Is there a thin alternative to plasterboard, say 5-6mm?



thanks
Chris

 

[roughcaster]

See if you can put up a picture on here Chris.

 

[Locoblade]

Sorry Ive just amended the above slightly as I realised there are purpose made cavity closers for bridging the cavity gap which I aaume I'll need to use and which answered half my question.

Anyway, here you go...

View media item 35121 View media item 35122
To keep dust down we had to drill the inside wall which has left it rather rough, adding to the problem slightly as being concrete block its not the easiest thing to tidy up.