I am having the shingles on my roof replaced. My roof has a ridge and
soffit attic ventilation system.
When I look up in the attic, I see there is a gap between the wooden
boards that make up the two sides of the roof. I assume the gap is
there for the air to flow thru. However the gap seems to be covered
with some black semi porous material right above the wood and does not
seem to allow a whole lot of air thru.
My question is.. when i look up thru the gap in the boards, should I
see some daylight that would tell me that there is a way for air to
pass freely? I can't see any daylight now and suspect air can't move
around that easily.
On Aug 17, 9:45 am, email@example.com wrote:
There are a variety of materials available for ridge vent solutions.
Some of them are porous dark material, almost like what you would see
in a room air conditioner filter. So, it's not unusual to not be able
to see daylight. When they do the shingles, they should put in a new
one anyway. So, you can do some research and find what kind u want.
On Aug 17, 11:54 am, firstname.lastname@example.org wrote:
I recently had my roof replaced and was wondering the same thing ...
after all, it needs a place for the hot air to escape. Anyway, the
men who did my roof came back yesterday to work on a house down the
street and I asked about my ridge vent. I found out it's called a
Cobra Ridge Vent ... (I had seen the box. But when I looked up from
beneath - into the attic - I could only see the cut away at the top
and solid black, like the bottom of a shingle on it. ) They showed me
a piece of foamy black stuff - one of the men blew into it and I could
feel his breath come out the other side. It was not rigid the way I
had expected. So it's possible you have the same thing. This stuff
would look black from the bottom.
On Fri, 17 Aug 2007 07:45:53 -0700, email@example.com wrote:
Well now think about it...if you could see daylight, what would
happen when it rains? :-) I know, you meant you would think you
should be able to see light...and I'll bet if you turned off all the
lights, you would see a little glow.
There are several styles of ridge vents, but probably the most common
is shingle over style. It's a flat woven plastic mat that gets laid
down over the gaps you mentioned. Then shingles are applied over the
top so it blends in fairly well with the roof. The air rises through
the slots in the sheathing, and then has to flow sideways through the
plastic mat until it exits from the thin edge of the material.
The material is made to allow a reasonable amount of air to flow,
while preventing insects from getting in.
It doesn't seem like much air will flow, but because it runs the whole
length (almost anyway, there is usual a foot or so at each end that
isn't vented) of the roof, it adds up to sufficient area to allow
In short, what you are describing sounds typical.
The attic air dows not go out and straight up. It goes out the sides of
the vent. The top if the ridge vent is covered to keep weather out. You
go up there on a hot day near the ridge vent. As hot as the roof is
you'll feel hoter air near the ridge vent.
Here's an animated airflow of how it works. Probably take forever on
I posted this question on another discussion - one about my roof. I
have just discovered that the roofers used the method you describe on
my own roof. The contract called for a Cobra ridge vent. Before I
start asking them to come back and fix it - I need to know (1) is the
method you describe as effective at moving hot air out as the Cobra
ridge vent? Is there anything about it that would void my warranty of
the shingles? I really don't want to have to go through the ordeal of
having them come back and do it over. We have had some really bad
rains lately - and the roof does not leak. My main concern is the
constantly running a/c and I wonder if the attic would be cooler with
a ridge vent. Your opinion would be appreciated.
Now I can answer part of my own question. The roofing contract calls
for a "Cobra ridge vent" and that is what I got. I just didn't get a
rigid vent. I hope that what I have works all right because I will
have to stay with it. My neighbor also has that written into her
contract but she did discuss it with him before he started working.
She has had problems with rats in the attic and told him she wanted a
"metal" vent or something to keep out rats. So, he may have installed
one in her attic or if not, he may come back and correct it. We
checked him out as thoroughly as possible before hiring him and he got
only good references. So, maybe it will be o.k. Now I better go do
some research on new air conditioners....got a feeling that's next.
The ridge vent is only part of the attic ventilation system. Do you
have adequate soffit vents so cool air can get in? Are you sure they
are not blocked by insulation, which is quite common? All too
frequently the insulation in the attic is installed with it shoved up
against, and blocking soffit vents. They have plastic shute type
baffles that should be stapled to the underside of the rood deck,
between rafters, for a few feet, starting at the low end of the roof,
by the soffit vents.
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