Retrofit soffit vent ideas
BreathinginSmoke
| Posted in General Questions on
Hi all,
I’m looking for advice on adding soffit ventilation. My attic was originally built as an unvented space with spray foam insulation, but we’re now transitioning to a traditional vented attic with ridge vents and soffit vents.
We’re removing the spray foam, replacing the roof, and installing ridge vents. The challenge is how to properly install soffit vents in existing Hardie soffit boards.
Any tips or best practices for venting through Hardie soffits?
Thanks!
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Replies
BiS,
This is what I have used. Available at Big Box stores. Easy to install with a hole saw.
https://plasticomponents.com/product/round-mini-louver-vents/
Malcolm's round vent suggest is probably best here, but it's going to suck installing those in hardie soffit board. You'll probably need a carbide hole saw, and you NEED PROTECTIVE CLOTHING AND A RESPIRATOR when cutting those holes. You do NOT NOT NOT want to breathe the silica dust coming off the saw while cutting!!!
It might be easier to just replace the soffit boards. Hardie makes vented soffit board with lots of little vent holes in a strip in the correct location. It might be easier to use vented PVC soffit boards though, which are also made for this purpose but are easier to work with in most cases.
Bill
If you use the vented Hardi soffit, strongly consider spraying the backside with spray adhesive and putting down a strip of fiberglass screen. The holes in my Hardi soffit are just large enough for mud daubers and baby hornets to crawl through them, so I'd try to avoid that.