Adding soffit venting to retrofit overhang?
I’m trying to help my mom lower her energy bills by upgrading the insulation and ventilation in our family home in Southern-Ontario, climate zone 5. It’s a storey-and-a-half with kneewall attics that was built in the ’50s and there’s one area on the south-east corner of the house that we’ve had problems with ice dams over the years. This part of the house was originally built with no overhang between the gable edge to the east and a valley about 4 feet to the west. New siding was added about 20-25 years ago and it looks like a retrofitted overhang was added to this part of the roof around the same time.
Unfortunately, no soffit venting was added to the new overhang when it was built and I’m wondering if I can add some now. I haven’t opened up the fascia or soffits for a look underneath yet, but from what I see inside the attic I think it was probably built like the attached picture. If add vented soffits, could I just drill some holes or cut some slots in the areas circled in red? Is there any reason not to do this? There are very few soffit vents in the house now, so I’m trying to open up as many areas as I can before I start adding more insulation.
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