Adding Vents to a House With No Soffits
I could use some advice on adding vents to my house which has a flat or almost flat roof on the very top and no soffits. I have a Second Empire Victorian House with a Mansard roof that is in Western Massachusetts. The top roof is a Firestone 60 mil TPO fully adhered roof which was put on top of 1″ polyisocyanurate insulation over modified bitumen roof. When we installed this roof I eliminated some of the vents which probably was a mistake.
I now plan to add insulation to the attic but am told I need vents in the roof. One roofer suggested two Lomanco Whirlybirds but also said it might not work because there were no lower intake vents. A Lomanco engineer recommended against his own vent because there are no lower vents and suggested a gravity vent made by Greenheck. But a Greenheck technical sales rep recommended against installing a gravity vents because I would be
expecting the air to flow in and flow out voluntarily.
You can see from these two picture that there is no place for soffits and that the roof is basically flat.
So what kind of vents should I install?
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