When we had plastering done the plasterer missed a small bit so when I try and fit skirting around where he missed I have a about a 10mm gap so I'm thinking of removing that bit of plaster back to the block wall but this will leave about a 20mm gap so can I use grab adhesive and glue a piece of 9.5mm plasterboard on to the block wall then glue another piece of plasterboard to the first piece to give me the gap I need.
If it’s a small area of wall which has not been made flush, how are your plastering skills? I have plastered or filled over small suspect areas of plaster in order to make them flush. I don’t trust myself with large areas but small areas are ok. You just feather in the edges so that it doesn’t show obvious joins.
I don't have a pic at the moment but it looks something like this. The brown strip on the right is architrave and the face of the architrave is pointing towards the side of the plug socket. The green patch is where he didn't plaster. I did think about filling the gap out with undercoat plaster to 20mm but as I only have a 2 inch wide gap to fill I though about sticking 2 pieces of plasterboard together.
Cut a bit of plasterboard and dot and dab in nice and level. Nearer and leveler the better. Fill and sand. Use toupret powder filler for the entire job. Only need to remove enough plaster to allow plaster board to fit and seal board edges and area with Pva