Draft in joist cavity

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Draft in joist cavity

Post by ziqbal_2000 » Thu Nov 09, 2017 10:43 pm


Just finishing drywalling the toilet and have a question. My air exchanger thick black pipe exit the house from the toilet ceiling. The joist cavity is cold and I can feel the draft in that cavity. I don’t think that builder has a done a good job of ceiling this one cavity.

Should I just ignore it considering it’s just one cavity, every other joist space is insulated and sealed properly OR I should do something about this. If yes, what can I do it considering there is very little access (see attached picture). One thing which I thought was to fill that space with expanding foam (may be stupid idea). Please advise?

Is 1/2 inch gap is acceptable gap for basement floating wall?

Thank you
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Re: Draft in joist cavity

Post by Shannon » Fri Nov 10, 2017 7:13 am

Yes you should try and seal that opening around the pipe with expanding foam to stop the draft.
1/2" space on a floating wall is not much I generally like to have 1" but I guess it depends on the soil conditions in your area and how much they move?
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