I have moved into a new house which has an extension, I have found that the extension was not insulated. I wish to cut out some plasterboard, lay the insulation and then replace. Any ideas? There are 4 sunken spotlights in the ceiling which are at least 1 metre apart.
It sounds like you will need to break apart, insulate properly and replace with new Plasterboard. I don't think there's a way to remove it without damaging.
I would recommend going with blown in cellulose insulation. You can drill 2 inch holes in the drywall, blow in the insulation, patch the holes and save a ton of money, time and materials. Cellulose is safe, cheap, easy to do yourself. Drill for walls, use the access door or put one in to do the attic. You may need to protect the areas around the ceiling lights due to heat dangers.
Are you taking down just the walls, just the ceiling, or everything ? If it's just the walls or ceiling, cut the seam with a sheetrock knife so you will have a clean joint to work to. If your taking the whole thing down, then it doesn't matter. Here's a hint. If you've never done this before, you might want to seek out a professional. Drywall looks easy, but it's not. Look for a house under construction and approach the guys working there for a name of a drywaller. Everybody in construction looks for side jobs. Buy the materials and pay the hangers and finishers in cash when they're done.
In my area it is law to have an attic hatch in any attic space, is this not the case where you are? If not do what do what Bub said and have an insulation contractor blow in the insulation through holes they drill then plug and plaster the holes. It usually costs around $1.00 per square foot for R32-40. don't tear down the plaster.
