Are attic baffles (store-bought) designed only for houses with ridge vents?
Looking to install some ADO Duravent baffles, being 11in wide, for 16in OC rafters (no time to build my own) before using Comfortbatt Rock wool double layers of R-30 in the attic.
It is and will remain an unconditioned attic, has two large Gable end vents, but needs more Soffit vents installed. (Not intending to cut in a ridge vent.) My main goal with the Baffles is mainly to block the Batts from being crammed into the Soffit inadvertantly. Also of course, hoping to promote air flow to the underside of roof plank decking.
Q1: Will the install of these Baffles serve an advantageous purpose despite the lack of ridge vent?
Q2: If so, Shall i install them as is, flat up against the roof decking with staples, just past the Top plate by a couple inches as advised by ADO install instuctions?
Q3: If not, would it be better to cut a hinge into the baffle at 7in up from the bottom of the 4 foot long baffle and install/staple that to the Top plate to block that space? ( as shown on YouTube by Mr Hardware)
Q4: And if yes to the Q3 scenario, would you advise for me to tape the perimster of that hinge i cut, sith a SIGA or Tyvek tzpe to make it air tight ( as these Baffles can have “windblocker” seals used with them but i dont have them locally, nor do they sound like they are appropriate to be used with old school rafters, as opposed to modern truss systems.
Q5: Is that air tight sealing at baffle edge necessary?
Thx for any pointers
Giovanni
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Replies
I think what you’re planning is to install batts in the attic floor and you want to use store-bought baffles to prevent the ends of the batts from clogging the soffit vents? If that’s the case, then the baffles will help. I don’t see a need to “hinge” the baffles since all the baffles are doing is connecting the soffit vents to the attic air space.
If you’re installing the batts in under the roof sheathing, and will install the baffles in the usual way (soffit to ridge), then I don’t see how that will work without using a ridge vent.
Since you said you have gable vents, I’m assuming you’re not trying to insulate the roof of the attic. I’d suggest considering blown cellulose instead of batts too — blown in insulation is great for attics, conforms to everything, and allows the joists to be easily covered.
Bill
Giovanni,
Ado Provent baffles are available in a variety of widths. For 16-inch-on-center rafters, you want the baffles that are 14 inches wide, not the baffles that are 11 inches wide.
These ventilation baffles are appropriate, even if your attic lacks a ridge vent, because you want air flow from your soffits to the unconditioned attic.
The Ado web site shows how these baffles are hinged at the bottom when installed above your top plates. The hinged portion is designed to be a wind-washing dam. (See illustration below.)
It's a good idea to install these with attention to airtightness, because wind-washing lowers the thermal performance of your insulation.
For more information on all of these issues, see "Site-Built Ventilation Baffles for Roofs."
Martin,
Thx for the unfo that the " baffles" are advantageous for all attics. All the documents i read refer to Ridge vents when speaking of the baffle or vent install.
The image u provided below of ADO company ...is the Durovent "baffle", only available in 24in on center. (The actual one i have doesnt have the hinge at bottom, is just a vent, calling them both Durovents"). The ADO ProVent you mention, comes in both a 16in OC "Vent" (no fold down hinge to attach to top plate/designed to be used with the Windblocker strip) and an 16 in OC All New Provent "Baffle"...in the 16in on center model....However, i am unable to locate either product ( the windblocker strip or the all new provent baffle 16in oc) for sale online to solve the issue of installing a baffle or vent in an airtight fashion, with the proper size, for my 16in OC rafters.
Do you see any simple way of adapting the 11 in vent that i do have access to...https://www.lowes.com/pd/ADO-Products-Durovent-22-in-x-48-in-Rafter-Vents/3012019
to provide for that air sealing?
( ie the gaps at the edges AND below the vent)... spray a large wad of spray foam beneath the vent on top plate or do the homemade hinging, and fill in with spray foam to air seal? / or using air sealing tape?
While this may not be the ideal approach (100%) ...if i can get 65-80% of the way there, its better than no vents and wind washed insulation...
i am trying to approach this task is the fewest steps as possible ( least amount of time), as i must begin installing the Rock Wool asap this week due to bank time requirements/ up and coming drywall scheduling.
Thx
Giovanni,
Q. "However, i am unable to locate either product ( the windblocker strip or the all new provent baffle 16in oc) for sale online."
A. Here are some links for Ado products.
Lowe's link
Home Depot link