We have had to change our bifold due to a fault with the doors. To get the doors out we have had to cut back the multifoil that wrapped into the door reveals.

Now I am not sure how to insulate/ detail this. Above the door there is a flitch plate beam door, thus no stud void for PIR like the rest of the timber frame. For this reason, I am particularly concerned with condensation risk in this area. Even though we don’t have the heating on yet there was already condensation on the back of the multi-foil (lucky the VCL seemed to be doing its job and the timber was dry.)

There is only about 25mm depth in the reveals, so I am considering 12mm PIR, then 12mm plasterboard. I am also considering removing the multi-foil from the wall above the door and replacing this with 50mm insulation-backed plaster board, and a new VCL?

Does anyone have any advice on how to insulate door reveals/ heads when there is little space?

Many Thanks

Sounds reasonable to me, I would cover a bit of the frame with the reveal lining and maximise insulation

Do you have multi foil insulation?

some comments on this thread:
http://www.greenbuildingforum.co.uk/newforum/comments.php?DiscussionID=17357

It could be the board that blunts the blade. I have offcuts and am happy to send you a piece for your interest. I gave a piece to my mate Gaz, who works on a building site, to show his colleagues - he said they passed it around at brew time like a piece of moon rock.

You can also get just the aerogel cloth itself, as blankets to wrap over things, or as a sticky-back cloth tape to stick onto cold bridge surfaces.

It's basically aerated sand dust, so perhaps it's quite abrasive.