Do I need an insulation blocker where attic meets sofit eaves
merges
| Posted in Expert Exchange Q&A on
Just moved in to a 12 year old house in Ontario, Canada and am having my attic insulation removed and replaced with cellulose R60. While taking this opportunity to air seal all attic penetrations, I stumbled on the situation below and hoping for some expert advise.
There is a total of 6 baffles for an attic space of about 1000 sq.ft. While investigating how to add more, I realized that there is nothing but a batt of fiberglass insulation material that separates the attic and sofit vent/eave. The way I see it, I have three options before the insulation company shows up::
* Install foam based block and/or baffle (as shown here https://www.greenbuildingadvisor.com/article/how-to-ventilate-rafter-bays-when-adding-insulation)
* Pay for a spray foaming over the fiber glass batt and creating a air barrier (the insulation company I have contracted do not do spray foam)
* Leave it as is
I have attached two pictures (with and without legend).
Appreciate any insights or advice!
Thanks
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Replies
merges,
A folded over batt blocking the blown insulation. You will probably find that detail in 9 out of 10 houses build in the last few decades in Ontario. The big problem is wind-washing, which is mitigated somewhat when the batt is compressed and pushed out past the exterior wall. If you decide to leave them it's not the end of the world.
Since you are taking out the original insulation, it might be worth putting in foam baffles while you are up there. Cellulose is pretty good at minimizing wind-washing. I wouldn't be to worried about meticulously air-sealing the baffles.
Thanks Malcolm