I have a 5 year old 2-story house in Dallas. Attic is about 1600 square
feet, and the roof is complex with a number of peaks and only a few
relatively short horizontal ridges. Ventilation is roughly to code,
using about a dozen 8 x 16 soffit vents and mushroom vents at or near
most peaks. Insulation is blow-in fiberglass and it's ok - about R-40.
I have 2 issues, would appreciate some advice.
First, in the Spring, on windy days, the airflow thru the vents pushes
loose-fill all over the place. I have to carefully rake it back into
place before the start of the cooling season each year. It's a real
pain. Does anyone else have this problem? I was thinking of installing
some sort of vertical baffles, like a thin plastic that I every 3rd
or 4th joist to help hold the heaps into place. Wouldn't fasten them
down as I do have to get to something electrical or plumbing every now
and then. Is this a good idea?
Second, in the Summer, on very hot calm days, the air stagnates in the
attic. I suspect it just doesn't have the "oomph" to make the S-turn
needed to flow out of the mushroom vents. It gets real hot up there.
The floor insulation keeps this out of the house proper, but the mile
of cheap AC flex duct soaks up a lot of heat and so does the underside
of the roof. I'd just like it a bit cooler up there, not looking for a
miracle. Was wondering if the addition of a medium size or slow moving
fan mounted a few feet off the attic floor under the highest roof peak,
with a tube extending upward to within a few feet of a cluster of
mushroom vents would help the convection along. Will this help?