I’d like to replace my shingle over 5/16" OSB (excellent
condition, but cheap materials) roof with a standing seam
The “attic” interior is inaccessible, just 18" high at
the ridge, down to nothing high at the eaves. There is
no eave overhang; the roof stops an inch past the
vertical plane of the exterior wall. This is a new
manufactured home, so I guess I don’t need to have
overhang and gutters to keep water from the foundation,
because I don’t have a foundation.
I’m willing to spend good money now to minimize costs,
both roofing and cooling (it gets warm in Texas) over the
next 30 years. I’m assuming costs of energy will go up
dramatically over that time span, as will inflation in
general. So best to do it now, for maximum benefit,
lowest cost, over time.
Currently the tiny “attic” is vented through the roof
with low profile cheap plastic vents – about 12 of them
in all, six of them high up near the ridge, six of them
low down. The roof is a simple gable, 3:12 pitch, 76 ft
long over a 16 ft wide home, so should be about 8.5 ft
from ridge to eave on the slant. That should be about
1290 sq ft of roof.
If I stayed with asphalt shingles, then this would be a
natural for SmartVent on the eave inlet vents.
Main question: But how in tarnation can I get inlet
ventilation with a metal roof, when I have no eave
overhang or soffits?
Related questions: What sorts of underlayment, vapor
barriers, radiant barriers (above the deck, blown in
chips over the blown in fiberglass, …?), air gaps
below the metal, and such would you recommend.
I supposed the outlet ventilation would be one of a
ridge vent or a row of dormers. I am concerned that
a ridge vent will impede the airflow too much.