Insulating A Roof Without Soffit Vents

Aside from the technical aspects of insulating and venting an attic without a soffit this is a project that requires both experience and expertise.

Insulating a roof without soffit vents.

Foam blocks airflow needs no vapor barrier and has a higher r value per inch than loose fill or batts so you ll get more protection with less depth. They call this a venting drip edge. To begin with the attic must be sealed to make the space airtight and to ensure that there is no air leakage. Typically you would have a gable vent on each end of the attic.

In cases where there is no under roof venting system no soffit intake vents no ridge vents a hot roof design is followed. If i had an older home without soffits i would strongly consider just completely air sealing the attic and adding foam insulation totally removing the need for ventilation. One great alternative to a soffit ventilation system is to install an intake vent right at the lower edge of the roof. Normal vented air likes to enter the attic lower down near the bottom third of the attic and as it passes through it will exit higher up near the top third of the attic space.

Venting solutions for roofs with no overhang or soffit. Install special roof intake venting products that work at the lower edge of the roof decking underneath the first course of shingles. The venting drip edge seems to be the easiest and most common way to go. Then cover the foam with drywall as required for fire safety.

With spray foam unlike with loose fill or batts you must cover the soffit vents they aren t needed to keep the roof cool. Weird attic layouts may be a part of it. In an attic without soffit vents you can add insulation in the corners and the wedges between the slope of the roof and the floor of the attic which serves as the ceiling for the room below. The roof cavity between rafters can be filled with insulation followed by installation of a perfect vapor barrier followed by finish surface of drywall or whatever else.

Smart vent a special roof eaves vent product that provides a 3 4 opening about 6 above the top of the roof drip edge. With old homes it can be very difficult to properly ventilate the attic for a variety of reasons.