In 1997 I had vinyl siding installed on my house, which is mostly brick.
The siding covers the soffit and fascia boards. When the siding was
installed, the 4x8 plywood soffit vents were removed, but the holes were
left of course. The vinyl siding has vented sections (2 ft wide) about
every 5 feet. The original plywood vents were 8-10 ft apart.

My concern is that the attic is not adequately ventilated. I'm not sure
that enough air is getting through the siding vents, then through the
plywood 4x8 holes. There is about 1/2 to 1 inch gap between siding and
original plywood soffit. I want to make sure the airflow is good enough
to ventilate the attic and help lower my energy bills.

The attic insulation is OK-I plan on adding some more.

What I am thinking about doing is removing the ventilated siding panels
(maybe not all of them), then cutting out more sections of the original
plywood soffit directly above the siding vent. Hopefully, this would allow
more airflow through the attic. The roof has 4 wind powered turbines, and I
may add 2 more.

Removing and re-installing the siding sections should not be a problem. The
house is about 2300 sq ft living area and was built in mid 70s.

I just wanted to get some opinions on whether the additional soffit vents in
the plywood would increase the attic airflow.

Without seeing it, it's impossible to give an answer. For one thing,
you only state that there are ventilated section of soffit every 5
feet, but not how long the ventilated sections are. We have no way of
knowing the amount of air intake in square inchs. What makes you
think there isn't adequate air flow?

thanks trader- the vent sections are 2 ft wide, soffit is about 3 ft
overhang.
actually, i don't know if there is adequate airflow or not. it was pointed
out by an insulation contractor that i probably was not getting enough with
the siding. his suggestion was to remove the entire siding along each side,
then remove the plywood underneath the siding. but this sounds pretty
extreme.

i live in texas-gets really hot in summer. attic temp gets to 140-150.


wrote in message
oups.com...
Without seeing it, it's impossible to give an answer. For one thing,
you only state that there are ventilated section of soffit every 5
feet, but not how long the ventilated sections are. We have no way of
knowing the amount of air intake in square inchs. What makes you
think there isn't adequate air flow?

"stevie" wrote in message ...

My concern is that the attic is not adequately ventilated. I'm not sure
that enough air is getting through the siding vents, then through the
plywood 4x8 holes.

Consult your municipal building office. It ought to be
able to tell you how many square inches of ventilation
each type of attic needs for 100 cubic feet of volume.
Minima are probably prescribed in the building code (for
new construction.)
--
Don Phillipson
Carlsbad Springs
(Ottawa, Canada)

On Thu, 26 Jan 2006 15:24:55 -0600, "stevie" wrote:

thanks trader- the vent sections are 2 ft wide, soffit is about 3 ft
overhang.
actually, i don't know if there is adequate airflow or not. it was pointed
out by an insulation contractor that i probably was not getting enough with
the siding. his suggestion was to remove the entire siding along each side,
then remove the plywood underneath the siding. but this sounds pretty
extreme.

i live in texas-gets really hot in summer. attic temp gets to 140-150.

140 is hot enough to burn the hair off a dogie.

Maybe you need a roof fan.


Remove NOPSAM to email me. Please let
me know if you have posted also.

Attic at 140 degrees is way too hot. I would do what the original
poster had in mind and add at least 2 electrical powered roof vents.

with your roof so hot it will fail sooner....

I had my house sided this past summer and when they were doing the soffit,
they took off all the siding and wood leaving just the joists and covered
that with the ventilated grid sections, so in other words, the whole front
soffit is vented, along with a ridge vent and a gable vent(2100sqft)...our
attic would reach 120 degrees, now with the fans, at least we know when it
reaches 100....and I'm only in NY.
"stevie" wrote in message ...
In 1997 I had vinyl siding installed on my house, which is mostly brick.
The siding covers the soffit and fascia boards. When the siding was
installed, the 4x8 plywood soffit vents were removed, but the holes were
left of course. The vinyl siding has vented sections (2 ft wide) about
every 5 feet. The original plywood vents were 8-10 ft apart.

My concern is that the attic is not adequately ventilated. I'm not sure
that enough air is getting through the siding vents, then through the
plywood 4x8 holes. There is about 1/2 to 1 inch gap between siding and
original plywood soffit. I want to make sure the airflow is good enough
to ventilate the attic and help lower my energy bills.

The attic insulation is OK-I plan on adding some more.

What I am thinking about doing is removing the ventilated siding panels
(maybe not all of them), then cutting out more sections of the original
plywood soffit directly above the siding vent. Hopefully, this would
allow
more airflow through the attic. The roof has 4 wind powered turbines, and
I
may add 2 more.

Removing and re-installing the siding sections should not be a problem.
The
house is about 2300 sq ft living area and was built in mid 70s.

I just wanted to get some opinions on whether the additional soffit vents
in
the plywood would increase the attic airflow.

Gntry wrote:
I had my house sided this past summer and when they were doing the soffit,
they took off all the siding and wood leaving just the joists and covered
that with the ventilated grid sections, so in other words, the whole front
soffit is vented, along with a ridge vent and a gable vent(2100sqft)...our
attic would reach 120 degrees, now with the fans, at least we know when it
reaches 100....and I'm only in NY.

My house, in SW CT, originally had no access to the attic; clearly a
stairwell was cut later. Upper ends of rafters are blackened,
apparently from the temps. (Only a couple of passive vents, at opposite
eaves.) One side of roof has three courses of 3-tabs (honest),
seemingly indicating a temperature problem, besides incompetence.

Installing powered exhaust fan, with thermostatic switch, really keeps
the temp under control up there now in August. For the OP, I'd suggest
that he give up on the passive turbines, since they are obviously not
working. They can probable be replaced by "mushroom"-looking powered
exhaust fans, with t-stat switch.

Expert advice might be needed, for sizing of fans and air-entry
passages.

HTH,
J

it would be easy to use a circular saw and cut out the plywood eave a
section where the holes in the vinyl are then put back.

"stevie" wrote in message ...
In 1997 I had vinyl siding installed on my house, which is mostly brick.
The siding covers the soffit and fascia boards. When the siding was
installed, the 4x8 plywood soffit vents were removed, but the holes were
left of course. The vinyl siding has vented sections (2 ft wide) about
every 5 feet. The original plywood vents were 8-10 ft apart.

My concern is that the attic is not adequately ventilated. I'm not sure
that enough air is getting through the siding vents, then through the
plywood 4x8 holes. There is about 1/2 to 1 inch gap between siding and
original plywood soffit. I want to make sure the airflow is good enough
to ventilate the attic and help lower my energy bills.

The attic insulation is OK-I plan on adding some more.

What I am thinking about doing is removing the ventilated siding panels
(maybe not all of them), then cutting out more sections of the original
plywood soffit directly above the siding vent. Hopefully, this would
allow
more airflow through the attic. The roof has 4 wind powered turbines, and
I
may add 2 more.

Removing and re-installing the siding sections should not be a problem.
The
house is about 2300 sq ft living area and was built in mid 70s.

I just wanted to get some opinions on whether the additional soffit vents
in
the plywood would increase the attic airflow.

"Installing powered exhaust fan, with thermostatic switch, really keeps

the temp under control up there now in August. For the OP, I'd suggest
that he give up on the passive turbines, since they are obviously not
working. They can probable be replaced by "mushroom"-looking powered
exhaust fans, with t-stat switch. "

Since he's concerned about air intake under the soffits, I wouldn't
jump to the conclusion that the ventilation at the top of the attic
needs to be fixed. Proper ventilation requires both intake and
exhaust. Unless he figures out how much intake he has and verifies
that it's sufficient, adding power vents is likely to do little to help
and could actually make things worse, by sucking cool air from the
living space, through outlets, gaps, etc.

I'm also not a big fan of powered vents period. A good ridge vent with
soffit intakes is widely recognized as the best solution. And it
doesn;t take any energy to run.

One thing I did at my previous house that really helped with the attic
temperature was to install something to block the heat from coming into the
attic space. I bought these rolls of quilted aluminum foil that had kraft
paper on the back. I stapled this stuff against the rafters (shiny side
down to keep dust from settling on the aluminum and decreasing the
reflectivity). It really helped.