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attic baffles installed incorrectly?

peterheynen1907 | Posted in General Questions on

Dear all,

I paid a company to insulate the house. They installed soffit vents, baffles, and blew in cellulose. They put in the baffles then blew in the cellulose. Is it a big deal that cellulose got in the baffles, potentially blocking ventilation for the soffit vents? Are the baffles too short? Or am I being too difficult / am I uninformed?

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  1. Expert Member
    BILL WICHERS | | #1

    Those baffles do look too short, but as long as they're open enough for air to flow through, you should be fine. Vent baffles out at the eaves serve two main purposes here:

    1- They keep the blown in insulation from getting out into the soffit and blocking the soffit vents. You can't really tell if they served that purpose from your pics, but let's hope that they did. Normally the baffles have to come down to the soffit on the soffit-side of the top plate of the exterior walls for them to protect the soffit vents). You can probably spot check your soffit vents in a few places to get an idea if the insulation got out into the soffit or not.

    2- They prevent wind washing of the edges of the insulation out over the top plates. For this to happen, the baffles just need to go from the bottom to the top of the layer of insulation you have, it's not really necassary for them to extend up past the top of the insulation layer.

    My own personal preference is to install the baffles aropund 18" or so up past the top of the layer of loose fill insulaiton that will be installed, but that's primarily just to make it easier for the insulating crew to avoid getting insulation into the baffles. Shorter baffles require more care on the part of the insulators to avoid insulation getting behind the baffles. As long as the air space created by the baffle between the baffle and the underside of the roof sheathing is open enough for air to circulate, the primary function of the baffle is maintained.


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