Air leakage and taping from the inside
rochellej
| Posted in Energy Efficiency and Durability on
Hi we have a new basement for a cottage. There is already house wrap up over wood boards on the outside. Should I tape, caulk or foam the gaps between the boards on the inside before I put R10 XPs and then R15 of mineral wool batt for the wood section?
Thank you
Rochelle, Nova Scotia
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Replies
Rochelle, that would be a huge amount of work and it would have an impact, but probably not in proportion to the effort. What is the housewrap? Most types are reasonably airtight; if they aren't covered with siding, careful work with tape would probably have a bigger impact than what you propose.
Thank you
I think you need one very good continuous air barrier. Two or five intermittent and incomplete air barriers waste lots of resources and achieve little or nothing.
Concentrate your efforts on making an air tight connection from your house wrap to the foundation.
Then work on getting the siding installed before the wind rips the house wrap as seem to always happen in the months most house wrap is left exposed.
Walta
I bought some 3m flashing tape and will do this thank you
"I bought some 3m flashing tape and will do this thank you"
Does the flavor of tape you bought require primer on concrete?
Walta
You wrote: "Should I tape, caulk or foam the gaps between the boards on the inside before I put R10 XPs and then R15 of mineral wool batt for the wood section?"
By "boards on the outside" so you mean 4x8 sheathing, made of OSB or zip type material?
By "put R10 XPS..." do you mean you plan to cut & cobble pieces of R10 XPS and place them between the stud bays, up against the inside surface of the sheathing, all from the inside? If so, place the XPS, then foam the perimeter to air seal the XPS to the studs. That will give you alot more air sealing than you have with the house wrap.
You should also work on the house wrap - is it good quality house wrap? Did you tape the seams? Can you tape it to the foundation using a high quality (and usually very expensive) tape?
Also, what climate zone are you in?
You can never do too much air sealing....
Boards are actual 2 by 6 wood. Not plywood or OSB. Yes xps on inside first. I will tape or foam the connections. Thank you for the advice. Climate zone 6