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 found:

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!

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 found:

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 I recently re-wired my house I put fireproof caulk in all of the
holes in the basement and the attic where the wires were run. The
difference was amazing as far as temperature in the basement. The
chimney effect was obviously the culprit.

-----------------------------------------------------------
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On Fri, 4 May 2012 05:17:18 -0700 (PDT), Limp Arbor
wrote:

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 found:

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.

The gable vents should permanently be closed off or the ridge vents will just
draw from them instead of the soffits.

When I recently re-wired my house I put fireproof caulk in all of the
holes in the basement and the attic where the wires were run. The
difference was amazing as far as temperature in the basement. The
chimney effect was obviously the culprit.

In the basement. Interesting. I've seen the wiring caulked in the attic but
not the basement.

On May 4, 9:18*am, "
wrote:
On Fri, 4 May 2012 05:17:18 -0700 (PDT), Limp Arbor
wrote:





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 found:

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.

The gable vents should permanently be closed off or the ridge vents will just
draw from them instead of the soffits.

Yet, as I stated in my description of the smoke test, the gable vents
are drawing air *out* not in.

"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."



When I recently re-wired my house I put fireproof caulk in all of the
holes in the basement and the attic where the wires were run. *The
difference was amazing as far as temperature in the basement. *The
chimney effect was obviously the culprit.

In the basement. *Interesting. *I've seen the wiring caulked in the attic but
not the basement.- Hide quoted text -

- Show quoted text -

On May 4, 9:18*am, "
wrote:
On Fri, 4 May 2012 05:17:18 -0700 (PDT), Limp Arbor
wrote:





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 found:

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.

The gable vents should permanently be closed off or the ridge vents will just
draw from them instead of the soffits.

When I recently re-wired my house I put fireproof caulk in all of the
holes in the basement and the attic where the wires were run. *The
difference was amazing as far as temperature in the basement. *The
chimney effect was obviously the culprit.

In the basement. *Interesting. *I've seen the wiring caulked in the attic but
not the basement.- Hide quoted text -


The electrical inspector told me I needed to caulk everywhere wires
went through a bottom plate or top plate with fireproof caulk.
Similar to what also needs to be done with plumbing now to prevent a
fire from rapidly moving from floor to floor.

No big deal but the caulk is a slimy mess until it cures.

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
found:
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?


Without sun on the roof, the chimney effect is going to be minimal. Testing on a
sunny day would be way more meaningful.

Gable vents are known to "short-circuit" the soffit/ridge vent flow. I have
thought about stapleing a layer of aluminum or fire resistant plastic to the
roof 2x4's in my attic to form a flow upward along the roof from the soffits,
and leaving the gable vents to vent the space under that. That might keep the
roof cooler than just blocking the gable vents.

On May 4, 10:59*am, "Bob F" wrote:
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
found:
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?

Without sun on the roof, the chimney effect is going to be minimal. Testing on a
sunny day would be way more meaningful.

Gable vents are known to "short-circuit" the soffit/ridge vent flow. I have
thought about stapleing a layer of aluminum or fire resistant plastic to the
roof 2x4's in my attic to form a flow upward along the roof from the soffits,
and leaving the gable vents to vent the space under that. That might keep the
roof cooler than just blocking the gable vents.- Hide quoted text -

- Show quoted text -

Still seems strange that the gable vents were drawing out, not in.

It could have been caused by Bernoulli's principle since the wind
outside could have caused less pressure outside the gable vents than
inside. However, I would think that the same thing would have happened
at the ridge, yet the ridge vent did not show any significant draw
either in or out.

I'm trying to make sure that everything is working before I pay the
contractor. He still has to install the gutters and the contract is
"payable upon completion". While I trust him to come back if there's a
problem, payment has a way of changing people's priorities.

Anyway, the forecast for weekend is mid-60's and sunny, so I'll
probably block the gables and see what happens. I may still have to
wait for a really hot day to see significant draw through the ridge
vent.

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 found:

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!

I would not cover the gable vents. IMO, it just serves
as more outlet area for the rising hot air. Even if you
got some air coming in from one or the other, hard
to imagine that it's not going to help cool the attic.

Your tests on a 50F day aren't going to show much.
You want a day with temps in the 70s+ and full sun.

If you want to experiment, try holding a smoke source
at the soffit vents with and without the gable vents
blocked. I'll bet you can't tell any difference.

On May 4, 12:52*pm, "
wrote:
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 found:

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!

I would not cover the gable vents. * IMO, it just serves
as more outlet area for the rising hot air. *Even if you
got some air coming in from one or the other, hard
to imagine that it's not going to help cool the attic.

Your tests on a 50F day aren't going to show much.
You want a day with temps in the 70s+ and full sun.

If you want to experiment, try holding a smoke source
at the soffit vents with and without the gable vents
blocked. *I'll bet you can't tell any difference.- Hide quoted text -

- Show quoted text -

Testing with the gable vents blocked was going to be my next step...I
just didn't have time last night.

I'm waffling about covering the gable vents. In talking to both
contractors and others, the majority say that they should be covered
but its sure not 100%.

The guy that actually did the roof basically shrugged and said it
shouldn't matter...it was up to me.

On May 4, 5:17*am, Limp Arbor wrote:
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 found:

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 I recently re-wired my house I put fireproof caulk in all of the
holes in the basement and the attic where the wires were run. *The
difference was amazing as far as temperature in the basement. *The
chimney effect was obviously the culprit.

Please explain......

You caulked the holes and it had an effect on basement or attic temps?

I would suggest that basement temp correlates well to soil temp and
less well to outside air temp.
Attic temp is a function of air temp, solar radiation and roof
construction.

I'd be hard pressed to belive that caulking Romex holes would have
much effect on basement temp..... maybe attic temp, but not a strong
effect.

cheers
Bob

On May 4, 1:18*pm, DerbyDad03 wrote:
On May 4, 12:52*pm, "
wrote:





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.

On May 4, 7:23*am, Limp Arbor wrote:
On May 4, 9:18*am, "
wrote:









On Fri, 4 May 2012 05:17:18 -0700 (PDT), Limp Arbor
wrote:

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 found:

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.

The gable vents should permanently be closed off or the ridge vents will just
draw from them instead of the soffits.

When I recently re-wired my house I put fireproof caulk in all of the
holes in the basement and the attic where the wires were run. *The
difference was amazing as far as temperature in the basement. *The
chimney effect was obviously the culprit.

In the basement. *Interesting. *I've seen the wiring caulked in the attic but
not the basement.- Hide quoted text -

The electrical inspector told me I needed to caulk everywhere wires
went through a bottom plate or top plate with fireproof caulk.
Similar to what also needs to be done with plumbing now to prevent a
fire from rapidly moving from floor to floor.

No big deal but the caulk is a slimy mess until it cures.

Talk about a 2nd order effect......... I wonder how much good caulking
plate holes really does.
The holes do have a piece of Romex in them and if the stud bays are
insulated,
then caulking plate holes would seem to fall into the ream of "turd
polishing".

Any one know the gensis of the requirement to caulk plate holes?

I know that in concrete structure floor to floor slab penetrations (as
for drain plumbing) require the use of fire-stop caulk to seal the
annulus around the pipes. However this gap has a much higher total
area then the un-filled portion of a hole for Romex.

A 1/2" gap around a 4" pipe is nearly 8 sq in... a 3/4" hole is
only .44 sq inches (an that's without the Romex)
Figure the Romex takes up 1/2 the area, we're down to .22 sq inches.

Any have some research data or code section that requires this?

cheers
Bob

On May 4, 1:28*pm, DD_BobK wrote:
On May 4, 7:23*am, Limp Arbor wrote:





On May 4, 9:18*am, "
wrote:

On Fri, 4 May 2012 05:17:18 -0700 (PDT), Limp Arbor
wrote:

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 found:

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.

The gable vents should permanently be closed off or the ridge vents will just
draw from them instead of the soffits.

When I recently re-wired my house I put fireproof caulk in all of the
holes in the basement and the attic where the wires were run. *The
difference was amazing as far as temperature in the basement. *The
chimney effect was obviously the culprit.

In the basement. *Interesting. *I've seen the wiring caulked in the attic but
not the basement.- Hide quoted text -

The electrical inspector told me I needed to caulk everywhere wires
went through a bottom plate or top plate with fireproof caulk.
Similar to what also needs to be done with plumbing now to prevent a
fire from rapidly moving from floor to floor.

No big deal but the caulk is a slimy mess until it cures.

Talk about a 2nd order effect......... I wonder how much good caulking
plate holes really does.
The holes do have a piece of Romex in them and if the stud bays are
insulated,
*then caulking plate holes would seem to fall into the ream of "turd
polishing".

Any one know the gensis of the requirement to caulk plate holes?

I know that in concrete structure floor to floor slab penetrations (as
for drain plumbing) require the use of fire-stop caulk to seal the
annulus around the pipes. *However this gap has a much higher total
area then the un-filled portion of a hole for Romex.

A 1/2" gap around a 4" pipe is nearly 8 sq in... * a 3/4" hole *is
only .44 sq inches (an that's without the Romex)
Figure the Romex takes up 1/2 the area, we're down to .22 sq inches.

Any have some research data or code section that requires this?

cheers

Based on this thread it is handled differently in diferent locales.
(like most things)
http://www.electriciantalk.com/f5/wh...equired-12394/

-----------------------------------------------------------
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Access your files from your smartphone or tablet
Bonus space provided using this link: http://db.tt/RIONkfbZ

On May 4, 1:25*pm, "
wrote:
On May 4, 1:18*pm, DerbyDad03 wrote:





On May 4, 12:52*pm, "
wrote:

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 found:

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!

I would not cover the gable vents. * IMO, it just serves
as more outlet area for the rising hot air. *Even if you
got some air coming in from one or the other, hard
to imagine that it's not going to help cool the attic.

Your tests on a 50F day aren't going to show much.
You want a day with temps in the 70s+ and full sun.

If you want to experiment, try holding a smoke source
at the soffit vents with and without the gable vents
blocked. *I'll bet you can't tell any difference.- Hide quoted text -

- Show quoted text -

Testing with the gable vents blocked was going to be my next step...I
just didn't have time last night.

I'm waffling about covering the gable vents. In talking to both
contractors and others, the majority say that they should be covered
but its sure not 100%.

The guy that actually did the roof basically shrugged and said it
shouldn't matter...it was up to me.- Hide quoted text -

- Show quoted text -

Everything I've seen is just based on personal opinion.
Mine included.
I've yet to see an actual study that was done to try to
determine what really happens. *And what really happens
is probably complex, depending on wind direction, speed,
temps. etc. *It could be that in certain circumstances having
both decreases the desired cooling and in some it helps.
Overall if I already had them, I'd just leave them on the
theory that hot air rises and more openings are probably
better than less.- Hide quoted text -

- Show quoted text -

That makes sense.

I wish I had thought to do a smoke test when all I had were the gable
vents and box vents. That might have given me a baseline for what the
gables were doing.

The most surprising part of last night's tests was that the gables
were sucking out, not in. I guess I expected that the ridge vent,
which is at the highest point, would take precedence and be the only
out bound opening, with everything else being intake.

That certainly wasn't what was happening.

On May 4, 1:21*pm, DD_BobK wrote:
On May 4, 5:17*am, Limp Arbor wrote:





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.

DerbyDad03 wrote:
I wish I had thought to do a smoke test when all I had were the gable
vents and box vents. That might have given me a baseline for what the
gables were doing.

The most surprising part of last night's tests was that the gables
were sucking out, not in. I guess I expected that the ridge vent,
which is at the highest point, would take precedence and be the only
out bound opening, with everything else being intake.

That certainly wasn't what was happening.

The gables are high, so if there's any heat source and no wind (or the correct
wind) they will naturally tend to flow out. The problem is that they provide an
easy way for air to get in to flow out the ridge vent. This will reduce the flow
from the soffits to the ridge, which works better to carry away the heat of the
sun baked roof. I imagine it also disturbs the air flow, spreading the heat
around the attic, rather than letting it flow smoothly from soffit to ridge and
out.

"DerbyDad03" wrote
Gable vents are known to "short-circuit" the soffit/ridge vent flow. I
have
thought about stapleing a layer of aluminum or fire resistant plastic to
the
roof 2x4's in my attic to form a flow upward along the roof from the
soffits,
and leaving the gable vents to vent the space under that. That might keep
the
roof cooler than just blocking the gable vents.- Hide quoted text -


Still seems strange that the gable vents were drawing out, not in.


I don't find it unusual at all. You have all the inlets at one level along
the soffits. Then you have a "group" of outlets five to ten feet above that
level that can allow the warm air to vent. The flow may change depending
on temperature, wind strength and direction.

On May 4, 11:25*am, DerbyDad03 wrote:
Still seems strange that the gable vents were drawing out, not in.

It could have been caused by Bernoulli's principle since the wind
outside could have caused less pressure outside the gable vents than
inside.

You said it was "breezy". My money is on the wind hitting one wall and
being deflected up, through the soffit vents, raising the pressure in
the attic and blowing the smoke out the biggest hole(s) not on the
same wall...

On May 4, 11:30*pm, Larry Fishel wrote:
On May 4, 11:25*am, DerbyDad03 wrote:

Still seems strange that the gable vents were drawing out, not in.

It could have been caused by Bernoulli's principle since the wind
outside could have caused less pressure outside the gable vents than
inside.

You said it was "breezy". My money is on the wind hitting one wall and
being deflected up, through the soffit vents, raising the pressure in
the attic and blowing the smoke out the biggest hole(s) not on the
same wall...

Wind was mainly from the west, hitting the side of the house where
there are no soffit vents. The soffit vents are on the north and south
walls of the house, so the wind would have been blowing across them.

In fact, there is a gable vent on both the east and west side of the
house. Both gable vents showed significant outflow, even the one on
the west wall.

Limp Arbor wrote in
:

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.


When I recently re-wired my house I put fireproof caulk in all of the
holes in the basement and the attic where the wires were run. The
difference was amazing as far as temperature in the basement. The
chimney effect was obviously the culprit.

-----------------------------------------------------------
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Access your files from your smartphone or tablet
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On May 5, 2:57*pm, Red Green wrote:
Limp Arbor wrote :









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.

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

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 found:

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!

An update:

Quite a bit warmer in the attic today and quite a bit more air flow
from the soffits up through the ridge vent.

I still haven't decided what to do about covering the gable
vents...need to do a little more research.

In any case, I'm quite happy with the roof/soffit/gutter installation.
The contractor was paid this morning.

On Fri, 04 May 2012 08:04:34 -0400, DerbyDad03
wrote:

I'm looking for opinions about what I'm seeing when I smoke test my new
ridge and soffit vents.

Isn't there a "NO SMOKING" sign in your attic? If not, there should be
one. Buy one at Walmart and install it immediately!

Smoking is dangerous and bad for your health!

DerbyDad03 used improper usenet message composition style by
unnecessarily full-quoting:

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...rotection.aspx

I don't buy the basic argument for that product.

I don't want the underlayment to "breath".

===========
Helps prevent inside moisture from becoming trapped within your roofing
system — and causing mold, mildew, and expensive structural damage
===========

If it can let water vapor / moisture pass through from the attic to the
outside, it can also let moisture pass the other direction as well. The
whole point of a roofing system is to have a water-tight covering over
the roof deck.

That GAF "Deck Armor" is a crock of ****. You don't solve an attic
humidity problem by having a "breathable" shingle underlayment. You
solve an attic humidity problem by (a) not venting kitchen and bathroom
fans into attic, and (2) have proper soffit and roof vents.

As for testing your ridge vent, don't bother doing any testing or
measuring on a cloudy day.

Go to any hardware store and buy a $5 or $10 digital thermometer that
has an indoor and outdoor temperature capability and it uses a small
thermocouple connected to 3 feet of wire as the outdoor sensor. If
you're handy with a soldering iron, extend the length of the wire with
some extra wire and place the outdoor sensor in the attic near the peak,
maybe a foot under the deck surface. Mount the readout unit somewhere
in the house where it's convienent.

I've done this, and mine will record min/max temperature as well, so I
know how hot it got on any given day.

If the max temp you ever see on the hottest day doesn't go above 120,
then you really don't have to do anything more or be too concerned. If
it hits 140 then you definately need to do something (like add a
ventilation fan).

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