With old homes it can be very difficult to properly ventilate the attic for a variety of reasons.
Insulating a roof without soffit vents.
In cases where there is no under roof venting system no soffit intake vents no ridge vents a hot roof design is followed.
Aside from the technical aspects of insulating and venting an attic without a soffit this is a project that requires both experience and expertise.
The venting drip edge seems to be the easiest and most common way to go.
To begin with the attic must be sealed to make the space airtight and to ensure that there is no air leakage.
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.
Typically you would have a gable vent on each end of the attic.
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.
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.
These specialty vents do not affect the.
Rafter vents or insulation baffles install in any rafter space to create narrow gaps that direct fresh air from the soffit vents to the peak of the roof.
Then cover the foam with drywall as required for fire safety.
One great alternative to a soffit ventilation system is to install an intake vent right at the lower edge of the roof.
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.
For an attic without soffit vents you may have the option to use gable vents instead.
They call this a venting drip edge.
Weird attic layouts may be a part of it.
Smart vent a special roof eaves vent product that provides a 3 4 opening about 6 above the top of the roof drip edge.
Venting solutions for roofs with no overhang or soffit.