Hello,
I'm converting my loft in a 1900's solid brick terrace house. Within the Eaves areas I have applied PIR board & insulated plasterboard to the inside of the roof area. However on the exposed internal & external walls within in the Eaves area I tried fixing plasterboard with dot & dab adhesive. However mould appeared on the plasterboard last winter which I believe was due to a cold bridge from the external walls through the dot and dab.
For cosmetic reasons I would like to be able to finish the brickwork within the Eaves with either a plaster or plasterboard finish. But if it's less risk not to do this then I am content to leave the existing brickwork.
Traditionally my house was designed to have had an open moisture system where water passes both internally/externally between the solid brickwork. I think rigid internal insulation solution might potentially cause me problems with condensation. I also have ceiling timbers embedded into the brickwork, so keen not to create any moisture problems that could potentially rot them them.
The options I'm thinking of are:
Option 1 – Do nothing. Leave the brickwork exposed and this will be breathable. Uncertain whether mould would form on the brickwork.
Option 2 – Apply an insulated lime/cork based plaster. Avoid bridging to the ceiling plasterboard so the lime doesn't eat the plasterboard. Leave a 50mm gap at bottom of plaster to allow ceiling timbers to get airflow.
Please would anybody be able to offer me some advice and opinions on how they would approach this?
Many Thanks,
