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Board insulation

Wailin · 2010-10-15 15:30:17

Just wondering can someone tell me whats the best way to use board insulation in an attic roof between the joists. I have large 8 by 4 sheets, do I cut them with a stanley knife or with a saw and should I put them up in long sheets between the joists or short? Whats the best way to prevent gaps between them also? Thanks in…

15-10-2010 03:30PM

#1

Wailin

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Posts: 4269

Just wondering can someone tell me whats the best way to use board insulation in an attic roof between the joists. I have large 8 by 4 sheets, do I cut them with a stanley knife or with a saw and should I put them up in long sheets between the joists or short? Whats the best way to prevent gaps between them also?
Thanks in advance.

Mod Edit: No need for product name here.

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Comments

#2 20-10-2010 01:24PM

beyondpassive

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Put an other sheet of 25 PIR board inside the rafters and tape it, its the only way to make it airtight and cold bridge free. I used to foam between board and rafter, but the foam wouldn't adhere to the timber.

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