on post from the below where I noticed the roof does not meet with the fascia and soffit to form a tight seal.

Is there supposed to be a gap between soffit and roof?

I have continued to investigate this issue and try to keep vermin out with a number of methods. So far, I've had success using sprayfoam with galvanized wire mesh to keep critters out. I also noted a huge amount of debris in the roof that is creating a stink in the walls and in the house. My house has vinyl siding with aluminum fascia and soffit. All along the perimeter there are soffit vents installed which look like this (i.e. perforated aluminum, cut to approximately 12" by 12" squares, every 8' or so along the house).

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However, when I pulled the soffit down to clean under it, I find that it is simply built on top of the existing (or previous) wood soffit. In other words, the vent doesn't vent at all.

In order to ensure proper attic ventilation, should I proceed to fill in the gaps around the roof? And then should I remove these fake vents and cut out a hole in the old wood soffit to allow ventilation? If I cut holes to ensure ventilation, is there any consideration for the size of the hole that I create. In other words, is there a formula to consider for a number of square inches of underside ventilation versus the total attic volume to keep insulation and space functional?

  • Really, the reason for that screening is to keep birds and bugs out of your attic.
    – Huesmann
    Commented Apr 9 at 12:56
  • @Huesmann I would agree if it were not completely covered up by the old wood fascia - which has no louvers or vents at all! Old homes seem to come with no shortage of surprises.
    – AdamO
    Commented Apr 9 at 16:15

1 Answer 1


As long as you have an outflow for heated air at roof ridge. I try to maintain at least double the square footage of inlet to outlet. Cooler air should easily enter soffit and then rise inside roof to exit at ridge (best) or gables( ok). I opened up what's commonly known as the bird board and added metal screen making sure insulation did not cover screen.

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