Insulating Attic Crawl Spaces

johnyjay

Hi,

I have 2 attic crawlspaces that I want to improve the insulation in.

I have attached a photo and the left hand side is the wall to a bedroom. (The photo got rotated for some reason, so its actually the bottom of the picture.)

Can I just put insulation board in between the joists against the bedroom wall and remove the fibreglass that's already there?

Does it need to be foil backed and if yes, which side does the foil go on?

Id really appreciate any help with this and any suggestions on the best way to improve this area!

I've also attached a picture of the door to this space if anyone can recommend a better, insulated door.

MicktheMan

This may not be the answer you're looking for ...

May I suggest that insulation in the wall is not the issue to address but rather the rooms likely suffer from excessive air leakage (or lack of airtightness).

While you could replace the fibre with a better quality insulation board etc, unless you address the air leakage you're likely wasting your time & money.

if you want to be sure, on a windy day get down on your hands and knees and feel around the floor to wall junction (skirting area) for air flow paying attention to the direction the wind is blowing. Get an incense stick and watch the smoke blow close to the skirt.

This issue gets fixed inside the room, not in the crawl space generally. Remove the skirt exposing the gap at the junction and using appropriate air tight tape and mastic seal this gap (between the wall and floor) on all 4 walls and refit the skirt. Belt and braces would be to also introduce an air tight membrane across the floor (lapped and taped) and seal this membrane to the bottom of the wall, lay a new laminate or other floor covering of choice and refit the skirting.

You will also have to air tighten the crawl space access door such that when it is closed no air can pass through at the edges.

Remember that generally insulation addresses conductive heat loss, air tightness addresses convective heat loss (aka draughts)

whizbang

Doesnt look like theres much insulaion in the rafters... maybe sort this first..

Almost all easily available of insulation board is double sided foil. nothing to worry about. Just screw it on over existing insulation.

insulation board is airtight, so just worry about airtightness to existing surfaces.