Seems like we need to replace a roof after most recent storm in our
(Dallas,TX) area.I'm thinking about putting impact resisting shingles and
since it requires
more ventilation I can't decide if I should put additional wind turbines
or have a solar fan installed instead. Our electric bill is not that high
during the summer so I'm not sure if there is any benefit of having a
solar vent + we have plenty of wind to keep turbines rolling.

Any advice will be appreciated.

-------------------------------------

texan1 wrote:
> Seems like we need to replace a roof after most recent storm in our
> (Dallas,TX) area.I'm thinking about putting impact resisting shingles and
> since it requires
> more ventilation I can't decide if I should put additional wind turbines
> or have a solar fan installed instead. Our electric bill is not that high
> during the summer so I'm not sure if there is any benefit of having a
> solar vent + we have plenty of wind to keep turbines rolling.
> 
> Any advice will be appreciated.
> 
Aren't wind turbines noisy?
What happens to them in high winds?

Lou

d...@foo.com (texan1) wrote in 
news:49e74cd4$0$31255$f...@news.usenetserver.com:

> Seems like we need to replace a roof after most recent storm in our
> (Dallas,TX) area.I'm thinking about putting impact resisting shingles and
> since it requires
> more ventilation I can't decide if I should put additional wind turbines
> or have a solar fan installed instead. Our electric bill is not that high
> during the summer so I'm not sure if there is any benefit of having a
> solar vent + we have plenty of wind to keep turbines rolling.
> 
> Any advice will be appreciated.

solar panels may not survive a storm;they can be broken,hail-damaged,etc.
They also get dirty and output drops until cleaned.

The wind turbine follows the KISS principle. 



-- 
Jim Yanik
jyanik
at
kua.net

"texan1" <d...@foo.com> wrote in message 
news:49e74cd4$0$31255$f...@news.usenetserver.com...
> Seems like we need to replace a roof after most recent storm in our
> (Dallas,TX) area.I'm thinking about putting impact resisting shingles and
> since it requires
> more ventilation I can't decide if I should put additional wind turbines
> or have a solar fan installed instead. Our electric bill is not that high
> during the summer so I'm not sure if there is any benefit of having a
> solar vent + we have plenty of wind to keep turbines rolling.
>
> Any advice will be appreciated.
>
>

I looked at solar powered vents too but I came to the conclusion they would 
have to be replaced periodically. I bought wind turbines and then we got hit 
by that hail storm in Austin. I had some roofers come out and one said he'd 
install a ridge vent for free, with a new roof of course. (Lon Smith 
Roofing, They are in Dallas too) I took that est. and called a local roofer 
and he said he could match it. So I took the turbines back to Homedepot.

Problem with turbines is you have to put in so many. I have a small 1700 sq 
ft house and the roofer told me I'd need 6 turbines.

Efficiency wise the ridge vent is supposed to be the best current technology 
and can be installed for about $450 to $800 for a 36 ft ridge on a single 
story. These are est. I got from two different roofers.

Let us know what you end up with.

od 

On Apr 16, 10:20=A0am, d...@foo.com (texan1) wrote:
> Seems like we need to replace a roof after most recent storm in our
> (Dallas,TX) area.I'm thinking about putting impact resisting shingles and
> since it requires
> more ventilation I can't decide if I should put additional wind turbines
> or have a solar fan installed instead. Our electric bill is not that high
> during the summer so I'm not sure if there is any benefit of having a
> solar vent + we have plenty of wind to keep turbines rolling.
>
> Any advice will be appreciated.

Since I live in the Dallas area as well, I have to comment on your
statement about having plenty of wind.  YES, we have plenty of wind
right NOW but not necessarily during the hottest part of the summer.
The wind turbines will however work even in light or no wind
conditions if you have good soffit venting as well.  The heat on the
roof will help to create a constant movement of air from the soffits
to the peak of the roof.  The wind turbines will allow that hot air to
escape while pulling in air from the soffits.  A solar powered fan
will produce a more active vent but only when the sun shines.

I used to have an electric powered vent that came on when the
temperature reached a certain point and would cut off when it cooled.
The problem with them was always NOISE!  They were very noisy and so
the last time I had the roof replaced, I opted of the ridge vent
system instead.  It works on the same principle as the turbine vents
and allows the hot air to excape while pulling cooler air from the
soffits.  If you are replacing the roof anyway, that would be the way
I would go.

On Apr 16, 4:54=A0pm, BobR  wrote:
> On Apr 16, 10:20=A0am, d...@foo.com (texan1) wrote:
>
> > Seems like we need to replace a roof after most recent storm in our
> > (Dallas,TX) area.I'm thinking about putting impact resisting shingles a=
nd
> > since it requires
> > more ventilation I can't decide if I should put additional wind turbine=
s
> > or have a solar fan installed instead. Our electric bill is not that hi=
gh
> > during the summer so I'm not sure if there is any benefit of having a
> > solar vent + we have plenty of wind to keep turbines rolling.
>
> > Any advice will be appreciated.
>
> Since I live in the Dallas area as well, I have to comment on your
> statement about having plenty of wind. =A0YES, we have plenty of wind
> right NOW but not necessarily during the hottest part of the summer.
> The wind turbines will however work even in light or no wind
> conditions if you have good soffit venting as well. =A0The heat on the
> roof will help to create a constant movement of air from the soffits
> to the peak of the roof. =A0The wind turbines will allow that hot air to
> escape while pulling in air from the soffits. =A0

I don't see that you get any mechanical advantage out of this scheme.
If there is enough wind blowing, I can see how a turbine vent can use
the wind power moving by the roof to move air out of the attic.  It's
using the force of the wind as power.   But I don't see how naturally
rising hot air moving from the soffit vents and up through the turbine
is doing any good beyond what just a plain similar size vent opening
would give.   In fact, it would seem to be worse, because there is
some energy loss in friction, etc with the turbine.

In other words, in still air, I think you'd be better off with just a
ridge vent.



>A solar powered fan
> will produce a more active vent but only when the sun shines.
>
> I used to have an electric powered vent that came on when the
> temperature reached a certain point and would cut off when it cooled.
> The problem with them was always NOISE! =A0They were very noisy and so
> the last time I had the roof replaced, I opted of the ridge vent
> system instead. =A0It works on the same principle as the turbine vents
> and allows the hot air to excape while pulling cooler air from the
> soffits. =A0If you are replacing the roof anyway, that would be the way
> I would go.

>Seems like we need to replace a roof after most recent storm in our
>(Dallas,TX) area.I'm thinking about putting impact resisting shingles
>and since it requires
>more ventilation I can't decide if I should put additional wind
>turbines or have a solar fan installed instead. Our electric bill is
>not that high during the summer so I'm not sure if there is any
>benefit of having a solar vent + we have plenty of wind to keep
>turbines rolling.

The first time you install a wind turbine, you'll discover that the
rotation doesn't actually do anything, except maybe keep rain out. The
turbine isn't fastened to a fan of any kind, so the square inches of
pipe is the only thing you need to consider. You need to have roughly
the same number of square inches of exit for hot air at the top of the
roof as you have inlet for cool air under the eaves.

The guy who recommended ridge vents has the best solution.

-- 
Steve Bell
New Life Home Improvement
Arlington, TX USA

On Apr 16, 5:10=A0pm, t...@optonline.net wrote:
> On Apr 16, 4:54=A0pm, BobR  wrote:
>
>
>
>
>
> > On Apr 16, 10:20=A0am, d...@foo.com (texan1) wrote:
>
> > > Seems like we need to replace a roof after most recent storm in our
> > > (Dallas,TX) area.I'm thinking about putting impact resisting shingles=
 and
> > > since it requires
> > > more ventilation I can't decide if I should put additional wind turbi=
nes
> > > or have a solar fan installed instead. Our electric bill is not that =
high
> > > during the summer so I'm not sure if there is any benefit of having a
> > > solar vent + we have plenty of wind to keep turbines rolling.
>
> > > Any advice will be appreciated.
>
> > Since I live in the Dallas area as well, I have to comment on your
> > statement about having plenty of wind. =A0YES, we have plenty of wind
> > right NOW but not necessarily during the hottest part of the summer.
> > The wind turbines will however work even in light or no wind
> > conditions if you have good soffit venting as well. =A0The heat on the
> > roof will help to create a constant movement of air from the soffits
> > to the peak of the roof. =A0The wind turbines will allow that hot air t=
o
> > escape while pulling in air from the soffits. =A0
>
> I don't see that you get any mechanical advantage out of this scheme.
> If there is enough wind blowing, I can see how a turbine vent can use
> the wind power moving by the roof to move air out of the attic. =A0It's
> using the force of the wind as power. =A0 But I don't see how naturally
> rising hot air moving from the soffit vents and up through the turbine
> is doing any good beyond what just a plain similar size vent opening
> would give. =A0 In fact, it would seem to be worse, because there is
> some energy loss in friction, etc with the turbine.
>
> In other words, in still air, I think you'd be better off with just a
> ridge vent.
>

If you read my last paragraph, I stated that I went with the ridge
vent as what I considered a better alternative.  The design of the
wind turbines is not really all that good at "pulling" air up through
the attic and mostly turn in the wind.  The real benefit to them is
providing an opening for the hot air to escape.  I think that a simple
covered vent would probably work almost a good.  The ridge vent
provides a much more effective area across the highest point of the
roof for the heat to escape.

>
>
> >A solar powered fan
> > will produce a more active vent but only when the sun shines.
>
> > I used to have an electric powered vent that came on when the
> > temperature reached a certain point and would cut off when it cooled.
> > The problem with them was always NOISE! =A0They were very noisy and so
> > the last time I had the roof replaced, I opted of the ridge vent
> > system instead. =A0It works on the same principle as the turbine vents
> > and allows the hot air to excape while pulling cooler air from the
> > soffits. =A0If you are replacing the roof anyway, that would be the way
> > I would go.- Hide quoted text -
>
> - Show quoted text -- Hide quoted text -
>
> - Show quoted text -

SteveBell wrote:
>> Seems like we need to replace a roof after most recent storm in our
>> (Dallas,TX) area.I'm thinking about putting impact resisting shingles
>> and since it requires
>> more ventilation I can't decide if I should put additional wind
>> turbines or have a solar fan installed instead. Our electric bill is
>> not that high during the summer so I'm not sure if there is any
>> benefit of having a solar vent + we have plenty of wind to keep
>> turbines rolling.
>
> The first time you install a wind turbine, you'll discover that the
> rotation doesn't actually do anything, except maybe keep rain out. The
> turbine isn't fastened to a fan of any kind, so the square inches of
> pipe is the only thing you need to consider. You need to have roughly
> the same number of square inches of exit for hot air at the top of the
> roof as you have inlet for cool air under the eaves.
>

This assertion can be debunked quite easily.

Simply stand under the turbine with a stick of incense and watch the smoke. 
Then stop the turbine and watch the smoke again. In the former case, the 
smoke is sucked out quite rapidly; in the latter case, the smoke goes 
nowhere.

A ridge vent - or hole in the roof - depends on a temperature difference 
between the air in the attic and that outside to generate convection 
currents.

A 12" wind turbine will move about 350 CFM of air in a 5MPH wind, 
irrespective of the temperature differential.

With no wind, the turbine acts like a ridge vent, dependent entirely on 
convection currents. 

BobR wrote:

> I used to have an electric powered vent that came on when the
> temperature reached a certain point and would cut off when it cooled.
> The problem with them was always NOISE!  They were very noisy and so
> the last time I had the roof replaced, I opted of the ridge vent
> system instead.  It works on the same principle as the turbine vents
> and allows the hot air to excape while pulling cooler air from the
> soffits.  If you are replacing the roof anyway, that would be the way
> I would go.

My understanding is that turbine effect of wind turbines doesn't really
do anything.  The hot air is actually removed by the thermal siphon
effect of hot air rising.  That's why mostly they recommend ridge
vents these days.

Also as one responder mentioned, it takes a lot
of turbines to really be effective.  When I had to replace one that
had failed I noticed on the box that they recommended 5 turbines
for a house my size.  My house had 2.  When I got a new roof last
year I went with ridge vents.

Bill