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Red Green

DerbyDad03 wrote in
:

On May 5, 2:57*pm, Red Green wrote:
Limp Arbor wrote
innews:23279a46-d108-4448-b3dc-
:

On May 4, 8:04*am, DerbyDad03 wrote:
I'm looking for opinions about what I'm seeing when I smoke test
my new ridge and soffit vents.

I had my roof replaced and a ridge vent was installed. I also had
full soffits vents cut and then covered with perforated vinyl. My
soffits are about 6" wide, so there's about 4" of perforated vinyl
showing.

The roof is framed such that I have about 3 feet of slanted
ceilings in the bedrooms, and the crawlspace attic itself is about
4 feet from the top of the ceilings joists to the rim.

There is bat insulation on the floor of the ceiling that extends
part way down the rafter bays towards the soffit. When I pull the
insulation out of the rafter bays, I can see light from the newly
cut soffit vents. The contractor said that the soffits themselves
are free of insulation.

I installed 4 feet of baffles in each rafter bay, pulling them
back about 4" from the soffits, per the contractor's instructions.
I then put the bat insulation back in the rafter bay making sure
the tops of the baffles are open. The insulation does not extend
more than 2' beyond the top of the baffle so I know it's not
covering the soffit vent.

Last but not least, I have a 12" x 12" gable vent at each end of
the house, which I have not yet closed off.

I bought some smoke matches to check the air flow and this is what
I foun
d:

The weather conditions were mid-50's F, thunderstorm, breezy. The
attic itself was fairly cool. I closed the access staircase so the
attic was closed off as it will be under normal conditions.

Holding a smoke match up inside a rafter bay near the ridge, there
was some movement up and out, but also a lot of smoke spreading
down and across the top of the attic. The was certainly no
indication of the smoke being rapidly sucked up and out through
the ridge vent.

Holding a smoke match inside a rafter bay near the top of a
baffle, there was movement up the rafter bay towards the ridge,
but it seemed more like natural up flow as opposed to strong
breeze blowing it upwards. If there was a breeze, it was not
significant.

Finally, holding a smoke match within an inch of either gable vent
showed significant outflow through the gable vent. It was
literally being sucked out of the vent at a rapid pace. If I
backed away from the gable vent 4 to 5 inches, the smoke just
floated upwards towards the ridge vent.

I suspect that I need to cover the gable vents, but based on what
I have described, do I need to be concerned that the soffit and
ridge vents are not operating properly? Do I need to wait until
it's really hot and try another smoke test?

Thanks!

Not an expert but from what I've read about it you need the gable
vents closed off for the ridge vent to start the chimney effect.
*You should be able to test by covering the gable vents with
plastic.

When they install ridge vents, roofers will often close them off with
roofing paper.

Wow...those would have to be some pretty dumb and/or non-caring
roofers.

....the gable vents, you clown ;-)

Besides, they didn't use tar paper on my roof.

I went with the GAF Lifetime Roofing System and no, they didn't cover
the vent with the Deck Armor.

http://www.gaf.com/roofing/residenti.../products.aspx