I'm planning to install internal wall insulation, with a focus on airtightness, so plan to do entire walls, slab to roof, and cold bridging.
The biggest concern I have right now is the 1st floor void and moisture. Our house is solid brick and the joists are pocketed into the wall. So if I don't get the airtightness right, warm moist air will reach the cold joist ends. Or if we have a leak outside (bad pointing etc) moisture could enter the brickwork and with the house being more insulated, there won't be the heat to push that moisture back out of the wall again. Both cases risk damaging the currently pocketed joist ends.
I'm considering detaching the joists from the wall, using a wall plate, that I'll thermally break, and fixing the joists to that using hangers.
From what I've seen the wall plate really needs bolting through to the outside wall to secure it, which I'd prefer not to do. Another option could be a steel joist for the existing timber joists to sit on, but that's probably beyond my DIYing capabilities!
Is there a better way?
The biggest concern I have right now is the 1st floor void and moisture. Our house is solid brick and the joists are pocketed into the wall. So if I don't get the airtightness right, warm moist air will reach the cold joist ends. Or if we have a leak outside (bad pointing etc) moisture could enter the brickwork and with the house being more insulated, there won't be the heat to push that moisture back out of the wall again. Both cases risk damaging the currently pocketed joist ends.
I'm considering detaching the joists from the wall, using a wall plate, that I'll thermally break, and fixing the joists to that using hangers.
From what I've seen the wall plate really needs bolting through to the outside wall to secure it, which I'd prefer not to do. Another option could be a steel joist for the existing timber joists to sit on, but that's probably beyond my DIYing capabilities!
Is there a better way?
