I have a small old two story house, and the top floor gets very hot during the day.
I'm thinking of installing one or two roof turbines, and also am considering putting
some insulation in above the ceiling, under the roof (I'm sure there isn't any right
now). I'd like to hear some opinions about these ideas, and would appreciate any other
suggestions. I like the idea of the roof turbines because they don't require anything
but a little wind to operate.

John

jbclem wrote:
I have a small old two story house, and the top floor gets very hot
during the day. I'm thinking of installing one or two roof turbines,
and also am considering putting some insulation in above the ceiling,
under the roof (I'm sure there isn't any right now). I'd like to
hear some opinions about these ideas, and would appreciate any other
suggestions. I like the idea of the roof turbines because they don't
require anything but a little wind to operate.

John

First I suggest you make sure the attic is vented according to the local
norms. Old homes often have insufficient ventilation. Just adding turbine
vents will not fix it. You need to have a way for fresh air to get into the
attic (usually soffit vents) and a way for the hot air to get out, usually
ridge or other vents placed high on the roof. In most areas this is
sufficient.

Insulation is a must, and even if you have some now, more is always
better. You also want a vapor barrier. What makes a good vapor barrier
depends on what your local weather is like (where do you live?)

Turbines are for those few areas or construction situations were
standard static venting does not work well. If you do decide on turbines, I
strongly suggest you get top quality units as the cheap ones are subject to
sort life, leaks and noise.

--
Joseph Meehan

Dia duit

jbclem wrote:
I have a small old two story house, and the top floor gets very hot
during the day.
I'm thinking of installing one or two roof turbines, and also am
considering putting
some insulation in above the ceiling, under the roof (I'm sure there
isn't any right
now). I'd like to hear some opinions about these ideas, and would
appreciate any other
suggestions. I like the idea of the roof turbines because they don't
require anything
but a little wind to operate.

John

I suggest you look at the Building Science Corporation web site.
It has * researched * information on venting and related issues.
Climate is an important part of deciding whether or not to vent an
attic.
TB

Convection from hot spaces drive them. Our garage went from 10° above
adjacent patio to 10° below when the turbine was put in during reroof.

On Mon, 23 May 2005 01:52:06 -0700, "jbclem"
wrote:

I have a small old two story house, and the top floor gets very hot during the day.
I'm thinking of installing one or two roof turbines, and also am considering putting
some insulation in above the ceiling, under the roof (I'm sure there isn't any right
now). I'd like to hear some opinions about these ideas, and would appreciate any other
suggestions. I like the idea of the roof turbines because they don't require anything
but a little wind to operate.

John

That's nice to know...if the convection drives the turbine than it would actually turn
without any wind. I like that 20 deg drop you got, that would be very nice in my
case...although your turbine was probably vented the entire garage, not just the
roof-celing area.

John



"nospambob" wrote in message
...
Convection from hot spaces drive them. Our garage went from 10° above
adjacent patio to 10° below when the turbine was put in during reroof.

On Mon, 23 May 2005 01:52:06 -0700, "jbclem"
wrote:

I have a small old two story house, and the top floor gets very hot during the day.
I'm thinking of installing one or two roof turbines, and also am considering putting
some insulation in above the ceiling, under the roof (I'm sure there isn't any right
now). I'd like to hear some opinions about these ideas, and would appreciate any
other
suggestions. I like the idea of the roof turbines because they don't require
anything
but a little wind to operate.

John

I didn't mention but this house is in Southern California, just outside Los Angeles in
the SM Mountains, an area called Topanga Canyon. I will check the old vents and also
look to see if there are soffit vents. I know there is one high vent at one end of the
house, the other end is two stories up and will be harder to check.

I plan on replacing the ceiling in the living room and that would be a good time to add
insulation. I didn't think of the vapor barrier, what exactly would it do? Is there a
specific kind of vapor barrier I would need. Also, would someone suggest the rating of
the insulation I would be looking for(thickness, R-? rating). I don't think there is
much area underneath the roof, I've only seen it once and I believe it was about 2 feet
at the peak. The celing in the living room doesn't start at the top of the wall but
rather is angled for about a foot from the walls and then becomes horizontal. That
angle is following the angle of the roof rafter(joist?) and I'm wondering if it may be
covering up the place where the soffit vents would be.

John


"jbclem" wrote in message ...
I have a small old two story house, and the top floor gets very hot during the day.
I'm thinking of installing one or two roof turbines, and also am considering putting
some insulation in above the ceiling, under the roof (I'm sure there isn't any right
now). I'd like to hear some opinions about these ideas, and would appreciate any
other
suggestions. I like the idea of the roof turbines because they don't require anything
but a little wind to operate.

John

jbclem wrote:
That's nice to know...if the convection drives the turbine than it
would actually turn without any wind.

What I wonder is if the convection is enough to turn the turbine, why
bother with the turbine when you already have the strong convection?

I like that 20 deg drop you
got, that would be very nice in my case...although your turbine was
probably vented the entire garage, not just the roof-celing area.

John



"nospambob" wrote in message
...
Convection from hot spaces drive them. Our garage went from 10°
above adjacent patio to 10° below when the turbine was put in during
reroof.

On Mon, 23 May 2005 01:52:06 -0700, "jbclem"
wrote:

I have a small old two story house, and the top floor gets very
hot during the day. I'm thinking of installing one or two roof
turbines, and also am considering putting some insulation in above
the ceiling, under the roof (I'm sure there isn't any right now).
I'd like to hear some opinions about these ideas, and would
appreciate any other suggestions. I like the idea of the roof
turbines because they don't require anything but a little wind to
operate.

John

--
Joseph Meehan

Dia duit

I read a project report once that said convection venting was more efficient
with a "tall" vent pipe than with a turbine.
I believe the vent pipe in that case was dark coated for solar heat
absorption, thus aiding the flue effect (along with some extra height).


Bill

"Joseph Meehan" wrote in message
. ..
jbclem wrote:
That's nice to know...if the convection drives the turbine than it
would actually turn without any wind.

What I wonder is if the convection is enough to turn the turbine, why
bother with the turbine when you already have the strong convection?

I like that 20 deg drop you
got, that would be very nice in my case...although your turbine was
probably vented the entire garage, not just the roof-celing area.

John



"nospambob" wrote in message
...
Convection from hot spaces drive them. Our garage went from 10°
above adjacent patio to 10° below when the turbine was put in during
reroof.

On Mon, 23 May 2005 01:52:06 -0700, "jbclem"
wrote:

I have a small old two story house, and the top floor gets very
hot during the day. I'm thinking of installing one or two roof
turbines, and also am considering putting some insulation in above
the ceiling, under the roof (I'm sure there isn't any right now).
I'd like to hear some opinions about these ideas, and would
appreciate any other suggestions. I like the idea of the roof
turbines because they don't require anything but a little wind to
operate.

John

--
Joseph Meehan

Dia duit

jbclem wrote:

...if the convection drives the turbine than it would actually turn
without any wind.

But turning them and the outgoing air takes energy, which slows that air,
compared to a gable or ridge vent or thermal chimney with the same area.

Nick

The 20° drop IS appreciated almost daily. The outrush of hot air when
the roofer cut the hole was impressive! Had his not oo long hair
waving for a few seconds. Not ceiling in the garage and mostly have a
door open for ease of access and replacement air as needed. Got the
$20.00 special from HD as that was all they had. No lube or problems
since installation about 10+ years ago. No planning just a thought as
they were reroofing.

On Mon, 23 May 2005 15:56:58 -0700, "jbclem"
wrote:

That's nice to know...if the convection drives the turbine than it would actually turn
without any wind. I like that 20 deg drop you got, that would be very nice in my
case...although your turbine was probably vented the entire garage, not just the
roof-celing area.

John



"nospambob" wrote in message
.. .
Convection from hot spaces drive them. Our garage went from 10° above
adjacent patio to 10° below when the turbine was put in during reroof.

On Mon, 23 May 2005 01:52:06 -0700, "jbclem"
wrote:

I have a small old two story house, and the top floor gets very hot during the day.
I'm thinking of installing one or two roof turbines, and also am considering putting
some insulation in above the ceiling, under the roof (I'm sure there isn't any right
now). I'd like to hear some opinions about these ideas, and would appreciate any
other
suggestions. I like the idea of the roof turbines because they don't require
anything
but a little wind to operate.

John

On Tue, 24 May 2005 02:23:00 GMT, "bill a"
wrote:

I read a project report once that said convection venting was more efficient
with a "tall" vent pipe than with a turbine.
I believe the vent pipe in that case was dark coated for solar heat
absorption, thus aiding the flue effect (along with some extra height).


My impression was that the point of a turbine isn't to be efficient,
although on a windy day, it helps. The point of a turbine is to keep
crap (and vermin) out of the vent pipe. Wasps don't like it when
their house moves.

nospambob wrote:
The 20° drop IS appreciated almost daily. The outrush of hot air when
the roofer cut the hole was impressive!

Which is a really good indication that you did not have enough high
vents to start with. Likely any added vent, including passive (ridge or any
non-powered roof vent) would have done very well. The turbine vents can add
some additional venting when there is a wind.

Had his not oo long hair
waving for a few seconds. Not ceiling in the garage and mostly have a
door open for ease of access and replacement air as needed. Got the
$20.00 special from HD as that was all they had. No lube or problems
since installation about 10+ years ago. No planning just a thought as
they were reroofing.

On Mon, 23 May 2005 15:56:58 -0700, "jbclem"
wrote:

That's nice to know...if the convection drives the turbine than it
would actually turn without any wind. I like that 20 deg drop you
got, that would be very nice in my case...although your turbine was
probably vented the entire garage, not just the roof-celing area.

John



"nospambob" wrote in message
. ..
Convection from hot spaces drive them. Our garage went from 10°
above adjacent patio to 10° below when the turbine was put in
during reroof.

On Mon, 23 May 2005 01:52:06 -0700, "jbclem"
wrote:

I have a small old two story house, and the top floor gets very
hot during the day. I'm thinking of installing one or two roof
turbines, and also am considering putting some insulation in above
the ceiling, under the roof (I'm sure there isn't any right now).
I'd like to hear some opinions about these ideas, and would
appreciate any other suggestions. I like the idea of the roof
turbines because they don't require anything but a little wind to
operate.

John

--
Joseph Meehan

Dia duit

I've seen the turbine turn when there was NO wind moving the leaves
outside though it was warm inside the garage. Turbines DO NOT NEED A
WIND TO TURN. Our garage didn't have any vents as built. Find the
definition of "convection" which is what warmer air rise.

On Tue, 24 May 2005 17:44:18 GMT, "Joseph Meehan"
wrote:

nospambob wrote:
The 20° drop IS appreciated almost daily. The outrush of hot air when
the roofer cut the hole was impressive!

Which is a really good indication that you did not have enough high
vents to start with. Likely any added vent, including passive (ridge or any
non-powered roof vent) would have done very well. The turbine vents can add
some additional venting when there is a wind.

nospambob wrote:
I've seen the turbine turn when there was NO wind moving the leaves
outside though it was warm inside the garage. Turbines DO NOT NEED A
WIND TO TURN. Our garage didn't have any vents as built. Find the
definition of "convection" which is what warmer air rise.

No they don't need wind to move. The natural flow of warm air will
cause them to turn, but that turning is actually slowing down the movement
of the air, you would get more movement if you removed the part that turns.


On Tue, 24 May 2005 17:44:18 GMT, "Joseph Meehan"
wrote:

nospambob wrote:
The 20° drop IS appreciated almost daily. The outrush of hot air
when the roofer cut the hole was impressive!

Which is a really good indication that you did not have enough
high vents to start with. Likely any added vent, including passive
(ridge or any non-powered roof vent) would have done very well. The
turbine vents can add some additional venting when there is a wind.

--
Joseph Meehan

Dia duit

I agree with you about the value of the turbine component. I think they are
primarily for the entertainment of the homeowner.

Bill

"Joseph Meehan" wrote in message
. ..
nospambob wrote:
I've seen the turbine turn when there was NO wind moving the leaves
outside though it was warm inside the garage. Turbines DO NOT NEED A
WIND TO TURN. Our garage didn't have any vents as built. Find the
definition of "convection" which is what warmer air rise.

No they don't need wind to move. The natural flow of warm air will
cause them to turn, but that turning is actually slowing down the movement
of the air, you would get more movement if you removed the part that
turns.