Hello again!

I ran a search, and I am nor confused than ever, plus I have some
other info from a contractor.

We have a 2 story, 2400 square foot "modern colonial" home (from what
I am told). LOL

Here is a picture of the house for reference:

http://farm1.static.flickr.com/205/4...09fe48e7_o.jpg

Our attic is insulated, with blown-in insulation. There is no storage
in the attic, and access is through a small access in our We have
ridge vents on the roof, with no other ventilation for the attic. We
were considering installing a whole house fan or maybe even an attic
fan. Are either of these a better option than the other? We would like
to lower the temperature of the house when it's cool outside (70-75
degrees) but warm inside (79-88 degrees).

I spoke with a friend who is a contractor. He seemed to thin an atic
fan without gable vents would not be effective, and that a whole house
fan would not give us the result we desire. Can anyone else inout on
this?


If you need additional info, please let me know.

Thank you,
Chris

Hi,

Live in Mass., also a Colonial.

All I can tell you is that the attic fan we installed many years ago in the
gable (belt driven) was probably the best thing we ever bought. We pull
down the steps leading up to the attic, run the fan for 5 minutes, and all
the hot summer air in the attic is gone. Works unbelievably well in cooling
off the house.

W have louvres in the fan end end, but very uncertain if they are needed.
Keep thinking attic ventillation from one screened end gable to this one
would be much better if I removed them ?
Not sure what function they actually provide ?

Anyone with any thoughts on this ?

Bob

-----------------------------------------------------
"Chris (SilverUnicorn)" wrote in message
...
Hello again!

I ran a search, and I am nor confused than ever, plus I have some
other info from a contractor.

We have a 2 story, 2400 square foot "modern colonial" home (from what
I am told). LOL

Here is a picture of the house for reference:

http://farm1.static.flickr.com/205/4...09fe48e7_o.jpg

Our attic is insulated, with blown-in insulation. There is no storage
in the attic, and access is through a small access in our We have
ridge vents on the roof, with no other ventilation for the attic. We
were considering installing a whole house fan or maybe even an attic
fan. Are either of these a better option than the other? We would like
to lower the temperature of the house when it's cool outside (70-75
degrees) but warm inside (79-88 degrees).

I spoke with a friend who is a contractor. He seemed to thin an atic
fan without gable vents would not be effective, and that a whole house
fan would not give us the result we desire. Can anyone else inout on
this?


If you need additional info, please let me know.

Thank you,
Chris

On Tue, 21 Jul 2009 04:35:15 -0700 (PDT), "Chris (SilverUnicorn)"
wrote:

Hello again!

I ran a search, and I am nor confused than ever, plus I have some
other info from a contractor.

We have a 2 story, 2400 square foot "modern colonial" home (from what
I am told). LOL

Here is a picture of the house for reference:

http://farm1.static.flickr.com/205/4...09fe48e7_o.jpg

Our attic is insulated, with blown-in insulation. There is no storage
in the attic, and access is through a small access in our We have
ridge vents on the roof, with no other ventilation for the attic. We
were considering installing a whole house fan or maybe even an attic
fan. Are either of these a better option than the other? We would like
to lower the temperature of the house when it's cool outside (70-75
degrees) but warm inside (79-88 degrees).

I spoke with a friend who is a contractor. He seemed to thin an atic
fan without gable vents would not be effective, and that a whole house
fan would not give us the result we desire. Can anyone else inout on
this?


If you need additional info, please let me know.

Thank you,
Chris

Where do you live? Tell us a lot about the local weather
including humidity. What do those in your area recommend and do.

Chris (SilverUnicorn) wrote:
Hello again!

I ran a search, and I am nor confused than ever, plus I have some
other info from a contractor.

We have a 2 story, 2400 square foot "modern colonial" home (from what
I am told). LOL

Here is a picture of the house for reference:

http://farm1.static.flickr.com/205/4...09fe48e7_o.jpg

Our attic is insulated, with blown-in insulation. There is no storage
in the attic, and access is through a small access in our We have
ridge vents on the roof, with no other ventilation for the attic. We
were considering installing a whole house fan or maybe even an attic
fan. Are either of these a better option than the other? We would like
to lower the temperature of the house when it's cool outside (70-75
degrees) but warm inside (79-88 degrees).

I spoke with a friend who is a contractor. He seemed to thin an atic
fan without gable vents would not be effective, and that a whole house
fan would not give us the result we desire. Can anyone else inout on
this?


If you need additional info, please let me know.

Thank you,
Chris
I would try a 20 inch box fan in an upstairs window.
Fit it snugly and use it to exhaust air. Then open other windows.
Close doors to rooms that you do not need to cool.
A much cheaper way to try to cool the house.
BTW I have done this and it works.

Lou

"Chris (SilverUnicorn)" wrote:

Hello again!

I ran a search, and I am nor confused than ever, plus I have some
other info from a contractor.

We have a 2 story, 2400 square foot "modern colonial" home (from what
I am told). LOL

Here is a picture of the house for reference:

http://farm1.static.flickr.com/205/4...09fe48e7_o.jpg

Our attic is insulated, with blown-in insulation. There is no storage
in the attic, and access is through a small access in our We have
ridge vents on the roof, with no other ventilation for the attic. We
were considering installing a whole house fan or maybe even an attic
fan. Are either of these a better option than the other? We would like
to lower the temperature of the house when it's cool outside (70-75
degrees) but warm inside (79-88 degrees).

I spoke with a friend who is a contractor. He seemed to thin an atic
fan without gable vents would not be effective, and that a whole house
fan would not give us the result we desire. Can anyone else inout on
this?

I'm with him. First spend your money on the gable vents. Then on
the attic fan. You will get some relief from an attic fan
now-- and a little more if you open the door to the attic and use it
to suck all the air through the house at night.

But the gable vents will act passively long before the thermostat on
the attic vent kicks in.

Looking at the picture I'm guessing that we're looking more or less
east. Are there good soffit vents and a ridge vent in that room
over the garage? That's where I'd start- with whatever roof has a
southern exposure. Do whatever you have to do to cool it off--
ventilate, insulate, spray water on it. . . .

Jim

On Jul 21, 6:35*am, "Chris (SilverUnicorn)"
wrote:
Hello again!

I ran a search, and I am nor confused than ever, plus I have some
other info from a contractor.

We have a 2 story, 2400 square foot "modern colonial" home (from what
I am told). LOL

Here is a picture of the house for reference:

http://farm1.static.flickr.com/205/4...09fe48e7_o.jpg

Our attic is insulated, with blown-in insulation. There is no storage
in the attic, and access is through a small access in our We have
ridge vents on the roof, with no other ventilation for the attic. We
were considering installing a whole house fan or maybe even an attic
fan. Are either of these a better option than the other? We would like
to lower the temperature of the house when it's cool outside (70-75
degrees) but warm inside (79-88 degrees).

I spoke with a friend who is a contractor. He seemed to thin an atic
fan without gable vents would not be effective, and that a whole house
fan would not give us the result we desire. Can anyone else inout on
this?

If you need additional info, please let me know.

Thank you,
Chris

How about a photo of the inside of the attic, You have to figure how
much air can go up the attic entrance and size it right, with added
gable vents how will it cool the area below, wont it just cool the
attic? just size it all right by cfm I am guessing.

Chris (SilverUnicorn) wrote:
Hello again!

I ran a search, and I am nor confused than ever, plus I have some
other info from a contractor.

We have a 2 story, 2400 square foot "modern colonial" home (from what
I am told). LOL

Here is a picture of the house for reference:

http://farm1.static.flickr.com/205/4...09fe48e7_o.jpg

Our attic is insulated, with blown-in insulation. There is no storage
in the attic, and access is through a small access in our We have
ridge vents on the roof, with no other ventilation for the attic. We
were considering installing a whole house fan or maybe even an attic
fan. Are either of these a better option than the other? We would like
to lower the temperature of the house when it's cool outside (70-75
degrees) but warm inside (79-88 degrees).

I spoke with a friend who is a contractor. He seemed to thin an atic
fan without gable vents would not be effective, and that a whole house
fan would not give us the result we desire. Can anyone else inout on
this?

You're thinking of sucking air in through a window or windows of the house,
right? In that case, you also have to have an exit for the hot air. The
ridge vent might suffice for a whole house fan assuming the vent area is
great enough.

For an attic fan, you also would have to have a way for air to get from the
lower house to the attic...opening a ceiling trap door would work but having
to open and close it would be a nuisance. Basically, as I understand it,
attic fans aren't meant to suck air from lower storeys but from the eaves
thus cooling the attic. I'd want gable vents too for that. The cooling
effect on the living area would depend largely on the effectiveness of the
insulation between it and attic...effective insulation = little cooling.

When I was in college I had a railroad apartment - full width living room,
hall from it to back, other rooms opening off the hall. Air conditioning
was uncommon and it was hot so I put a window fan in the front window,
opened one in the back. Worked well, nice breeze and the breeze was
controllable simply by closing/opening a window where the breeze was wanted.

Almost 50 years later when we built a house I remembered how effective that
window fan was and put in two "whole house" fans...one in the house, one in
my shop. Both work very well but we never use the one in the house because
of the noise. Lots of noise. Freight train type noise. The one in the
shop I use a good bit because there is generally already a lot of noise and
it helps get rid of wood particles in the air (it vents into a small, closed
area with a gable vent in the attic)

In short, I'm thinking a couple of window fans might work better for you.
..
--

dadiOH
____________________________

dadiOH's dandies v3.06...
....a help file of info about MP3s, recording from
LP/cassette and tips & tricks on this and that.
Get it at http://mysite.verizon.net/xico

Chris (SilverUnicorn) wrote:
Hello again!

I ran a search, and I am nor confused than ever, plus I have some
other info from a contractor.

We have a 2 story, 2400 square foot "modern colonial" home (from what
I am told). LOL

Here is a picture of the house for reference:

http://farm1.static.flickr.com/205/4...09fe48e7_o.jpg

Our attic is insulated, with blown-in insulation. There is no storage
in the attic, and access is through a small access in our We have
ridge vents on the roof, with no other ventilation for the attic. We
were considering installing a whole house fan or maybe even an attic
fan. Are either of these a better option than the other? We would like
to lower the temperature of the house when it's cool outside (70-75
degrees) but warm inside (79-88 degrees).

I spoke with a friend who is a contractor. He seemed to thin an atic
fan without gable vents would not be effective, and that a whole house
fan would not give us the result we desire. Can anyone else inout on
this?

The first thing I would suggest is to add low vents to the soffets and maybe low
in the end walls, near where the roof meets the bottom of the attic. This will
produce way better flow of air up through the attic, cooling it and the house
significantly.

I bought a "gable fan" at a thrift shop. Something like:
http://www.nextag.com/BROAN-353-NA-G...96/prices-html
My fan is more powerful than a standard window fan of similar size.

I put it in the opening to the attic, with an X10 remote control module on its
power to control it. It functions as a small whole house fan, sucking air up
from the house through the attic. This could be an easy thing to do which
doesn't coast so much. I just slipped chunks of pipe insulation over the four
mounting arms, and set it over the attic access hole, with the pipe insulation
on the wood to isolated vibration and noise from the house structure. Open
appropriate windows to produce airflow through the house, from the farthest
windows to the fan.

You may need to bypass the built in thermostat in the fan so it will operate at
lower temps.

The fan needs to be small enough to fit in the attic access door, and large
enough to fill most of the hole. Baffles could be added to decrease backflow
from the attic.

Here in Seattle, I run the fan at night, cooling the house off, then turn it off
in the morning, closing the windows and curtains. The house will still be 5-9 F
cooler than outside by the evening.

"Chris (SilverUnicorn)" wrote in message
...
Hello again!

I ran a search, and I am nor confused than ever, plus I have some
other info from a contractor.

We have a 2 story, 2400 square foot "modern colonial" home (from what
I am told). LOL

Here is a picture of the house for reference:

http://farm1.static.flickr.com/205/4...09fe48e7_o.jpg

Our attic is insulated, with blown-in insulation. There is no storage
in the attic, and access is through a small access in our We have
ridge vents on the roof, with no other ventilation for the attic. We
were considering installing a whole house fan or maybe even an attic
fan. Are either of these a better option than the other? We would like
to lower the temperature of the house when it's cool outside (70-75
degrees) but warm inside (79-88 degrees).

I spoke with a friend who is a contractor. He seemed to thin an atic
fan without gable vents would not be effective, and that a whole house
fan would not give us the result we desire. Can anyone else inout on
this?


If you need additional info, please let me know.

Thank you,
Chris

In my first house I cut holes in my roof and installed two wind turbines.
There was a very noticeable difference in the comfort level of the house
when I came home from work in the summer. I then installed a whole-house
fan but needed to add another vent to exhaust the attic air because the
total square footage of the existing vents was less than the area of the
fan. I added this vent so it exhausted into the garage which, after the
attic had cooled, helped to ventilate the garage. The attic fans usually
have a louvered shutter that opens automatically when the fan is on, either
by the force of the fan or with a motor. This was a one-story, 1350 sq/ft
house with poor insulation and the attic fan was a great improvement.

My second house was a two-story, also poorly insulated. I installed an
attic fan and it seemed to help somewhat, but not as well as the first
house. I got better cooling results at night by putting a 20" box fan in
the window blowing inwards.

Now I have a new manufactured home with no attic but it is very well
insulated and 20" box fans in the window are about my only choice and they
work quite well as long as it's below 70 outside. On cooler nights I only
need to use a 120mm 12 volt cooling fan.

Judging from my experience just about any way that you decide to remove the
hot air from the attic is going to help, especially if someone is going to
be using air conditioning. With wind turbines or an attic fan you would not
be pulling air through the house, only the attic so air conditioning could
be operated at the same time. With an attic fan it's more like one or the
other.

Chris (SilverUnicorn) wrote:
Hello again!

I ran a search, and I am nor confused than ever, plus I have some
other info from a contractor.

We have a 2 story, 2400 square foot "modern colonial" home (from what
I am told). LOL

Here is a picture of the house for reference:

http://farm1.static.flickr.com/205/4...09fe48e7_o.jpg

Our attic is insulated, with blown-in insulation. There is no storage
in the attic, and access is through a small access in our We have
ridge vents on the roof, with no other ventilation for the attic. We
were considering installing a whole house fan or maybe even an attic
fan. Are either of these a better option than the other? We would like
to lower the temperature of the house when it's cool outside (70-75
degrees) but warm inside (79-88 degrees).

I spoke with a friend who is a contractor. He seemed to thin an atic
fan without gable vents would not be effective, and that a whole house
fan would not give us the result we desire. Can anyone else inout on
this?


If you need additional info, please let me know.

Thank you,
Chris
Hi,
Where are you located? Having ridge vent, you need extra ventilation?
First you have to find out whether you need extra vent. or not.
Also what is R value of your atic insulation?(how thick?)

On Jul 21, 10:08*am, Tony Hwang wrote:
Chris (SilverUnicorn) wrote:
Hello again!

I ran a search, and I am nor confused than ever, plus I have some
other info from a contractor.

We have a 2 story, 2400 square foot "modern colonial" home (from what
I am told). LOL

Here is a picture of the house for reference:

http://farm1.static.flickr.com/205/4...09fe48e7_o.jpg

Our attic is insulated, with blown-in insulation. There is no storage
in the attic, and access is through a small access in our We have
ridge vents on the roof, with no other ventilation for the attic. We
were considering installing a whole house fan or maybe even an attic
fan. Are either of these a better option than the other? We would like
to lower the temperature of the house when it's cool outside (70-75
degrees) but warm inside (79-88 degrees).

I spoke with a friend who is a contractor. He seemed to thin an atic
fan without gable vents would not be effective, and that a whole house
fan would not give us the result we desire. Can anyone else inout on
this?

If you need additional info, please let me know.

Thank you,
Chris

Hi,
Where are you located? Having ridge vent, you need extra ventilation?
First you have to find out whether you need extra vent. or not.
Also what is R value of your atic insulation?(how thick?)- Hide quoted text -

- Show quoted text -

Thank you for the replies.

We live outside of Philadelphia, PA. The house does have dual zone
centeral air. The ridge vents are the only ventilation. Wait....I
think we have soffit vents as well. Sorry, I don't know all the
terminology. There are grated panels every so often under the edges of
the roof. I think these are soffit vents?

This stuff: http://www.wood-whitacreroofing.com/images/100_0262.JPG

That we have as well. Sorry for the lack of information.

Chris

Chris (SilverUnicorn) wrote:
We live outside of Philadelphia, PA. The house does have dual zone
centeral air. The ridge vents are the only ventilation. Wait....I
think we have soffit vents as well. Sorry, I don't know all the
terminology. There are grated panels every so often under the edges of
the roof. I think these are soffit vents?

This stuff: http://www.wood-whitacreroofing.com/images/100_0262.JPG

Yes, those are soffit vents. The attic vents - be they ridge or otherwise -
are meant to allow hot air to escape. The air escaping draws fresh air in
via the soffits. This continuous convection cools the attic. Not chilly
cool, just cooler than if there were no convection.


--

dadiOH
____________________________

dadiOH's dandies v3.06...
....a help file of info about MP3s, recording from
LP/cassette and tips & tricks on this and that.
Get it at http://mysite.verizon.net/xico

On Jul 21, 9:17*am, "dadiOH" wrote:

Almost 50 years later when we built a house I remembered how effective that
window fan was and put in two "whole house" fans...one in the house, one in
my shop. *Both work very well but we never use the one in the house because
of the noise. *Lots of noise. *Freight train type noise. *

There have been significant improvements in quieting fan noise. The
newer ones aren't nearly as bad.

The one in the
shop I use a good bit because there is generally already a lot of noise and
it helps get rid of wood particles in the air (it vents into a small, closed
area with a gable vent in the attic)

I'd be a bit leery about blowing saw dust into an enclosed space
without filtering it first. I'd also wonder about the dust building
up on the motor and potentially overheating. Do you inspect/clean the
fan often?

R

RicodJour wrote:
On Jul 21, 9:17 am, "dadiOH" wrote:

Almost 50 years later when we built a house I remembered how
effective that window fan was and put in two "whole house"
fans...one in the house, one in my shop. Both work very well but we
never use the one in the house because of the noise. Lots of noise.
Freight train type noise.

There have been significant improvements in quieting fan noise. The
newer ones aren't nearly as bad.

The one in the
shop I use a good bit because there is generally already a lot of
noise and it helps get rid of wood particles in the air (it vents
into a small, closed area with a gable vent in the attic)

I'd be a bit leery about blowing saw dust into an enclosed space
without filtering it first. I'd also wonder about the dust building
up on the motor and potentially overheating. Do you inspect/clean the
fan often?

Often no; from time to time, yes.

Very little accumulates, almost all is blown out the (largish) gable vent.
From there it drifts around until it finally settles somewhere on our 10
acres. Once settled it decays trying futilely to enrich the sand that
passes for soil in Florida.



--

dadiOH
____________________________

dadiOH's dandies v3.06...
....a help file of info about MP3s, recording from
LP/cassette and tips & tricks on this and that.
Get it at http://mysite.verizon.net/xico

Chris (SilverUnicorn) wrote:

Thank you for the replies.

We live outside of Philadelphia, PA. The house does have dual zone
centeral air. The ridge vents are the only ventilation. Wait....I
think we have soffit vents as well. Sorry, I don't know all the
terminology. There are grated panels every so often under the edges of
the roof. I think these are soffit vents?

This stuff: http://www.wood-whitacreroofing.com/images/100_0262.JPG

That we have as well. Sorry for the lack of information.

Most experts recommend 1 sq in of unobstructed soffit vent for each 1 sq ft
of attic space. Assuming you have 1200 sq ft of attic space in a 2-story,
2400 sq ft home, you need 1200 sq in of soffit vents. That's an unobstructed
vent totalling 1x8 feet.

The picture of venting material you provided is 98%+ obstructed. I'd say you
need 400 linear feet of that stuff to reach the suggested level.

On Tue, 21 Jul 2009 04:35:15 -0700 (PDT), "Chris (SilverUnicorn)"
wrote:

Hello again!

I ran a search, and I am nor confused than ever, plus I have some
other info from a contractor.

We have a 2 story, 2400 square foot "modern colonial" home (from what
I am told). LOL

Here is a picture of the house for reference:

http://farm1.static.flickr.com/205/4...09fe48e7_o.jpg

Our attic is insulated, with blown-in insulation. There is no storage
in the attic, and access is through a small access in our We have
ridge vents on the roof, with no other ventilation for the attic. We
were considering installing a whole house fan or maybe even an attic
fan. Are either of these a better option than the other? We would like
to lower the temperature of the house when it's cool outside (70-75
degrees) but warm inside (79-88 degrees).

I spoke with a friend who is a contractor. He seemed to thin an atic
fan without gable vents would not be effective, and that a whole house
fan would not give us the result we desire. Can anyone else inout on
this?


If you need additional info, please let me know.

Thank you,
Chris

If your primary aim is to cool the house then you want a whole house
fan. An attic fan will pull much of it's air from the vents in the
attic, which helps cool the attic, but doesn't do as much for the
house. Whole house fans with automatic, tight sealing insulated doors
are available, and they are very quiet and energy efficient,
especially compared to older versions.

See for example:
http://www.airscapefans.com/?gclid=C...FZJM5QodG3cP5w

(A bit pricey, though, I might add)

You have to open a couple of windows when you run it, and you need
enough vent area in the attic to exhaust the air, but otherwise they
are fairly easy to install and use. The site above has good info on
vent area needed, installation, etc.

Note that there are some disadvantages:

First, compared to air conditioning, you will be pulling more dust and
dirt into the house.

Second, if you are using the WWF at night and in the morning, and then
turning on the air conditioning during the hot part of the day, and
you are in an area where it is very humid, you may not save very much
over just running the a/c all the time. This is because it takes more
energy to cool and dehumidify the air when it starts out with lots of
humidity. The a/c cools and dehumidfies the air, then you run the WWF
and pull a bunch of humidity into the house at night, then the a/c has
to remove that the next day, and so on.... There are WWF sites out
there that have charts that show (probably somewhat overblown) what
sort of energy savings you can anticipate in various regions of the
country.

HTH,

Paul F.

On Jul 21, 6:35*am, "Chris (SilverUnicorn)"
wrote:
Hello again!

I ran a search, and I am nor confused than ever, plus I have some
other info from a contractor.

We have a 2 story, 2400 square foot "modern colonial" home (from what
I am told). LOL

Here is a picture of the house for reference:

http://farm1.static.flickr.com/205/4...09fe48e7_o.jpg

Our attic is insulated, with blown-in insulation. There is no storage
in the attic, and access is through a small access in our We have
ridge vents on the roof, with no other ventilation for the attic. We
were considering installing a whole house fan or maybe even an attic
fan. Are either of these a better option than the other? We would like
to lower the temperature of the house when it's cool outside (70-75
degrees) but warm inside (79-88 degrees).

I spoke with a friend who is a contractor. He seemed to thin an atic
fan without gable vents would not be effective, and that a whole house
fan would not give us the result we desire. Can anyone else inout on
this?

If you need additional info, please let me know.

Thank you,
Chris

Generally "whole house fan" refers to a fan mounted in the ceiling of
the top floor; it sucks air out of the house and blows it into the
attic. For this to be effective, the attic must be well-ventilated;
i.e. there must be lots of ways air can then get from the attic to
outside. Adequate venting for a whole house fan requires a little bit
of calculation: generally you need a vent area equal to the area of
the fan. But for a vent with screen over it (which they all have),
you have to reduce the area by some percentage (because the screen
restricts the flow somewhat) to get the "effective area." So if
installing a whole house fan, you would need to add up all the attic
vents and calculate their effective area, to see if you have enough
venting to match the area of the fan you want to install. If not add
venting. A competent contractor should be able to do all that. I
just followed the instructions that came with my fan. When the fan
operates, it sucks outside air into the house (must have windows
open), so it is ventilating the house, and is also ventilating the
attic since the house air gets blown into the attic and then from the
attic outside.

I installed whole-house fans in both houses I have owned; I like
them. My climate is fairly similar to yours, at least in summer -
variably hot and humid. As long as it cools off at night, I find the
fan a nice alternative to AC. But as others have mentioned, you won't
necessarily save a lot of energy. And some nights it will just not
cool off enough to make it comfortable. Also I will say using a
whole house fan requires a little bit of operational savvy; you get a
nice breeze wherever you open a window, but you may have to prop the
door open in that room so it doesn't slam shut. It's not rocket
science but not completely foolproof. Whole house fans usually come
with a timer switch so you can set it to run for, say, three hours,
then shut off (good when you're going to bed and don't want it to run
all night).

An "attic fan" or "attic ventilation fan" is mounted in the attic (in
a gable or the roof) and sucks air out of the attic and blows it
outside. Again, the attic must be well vented for it to work right;
if there is not enough venting, some might have to be added. Attic
fans are usually smaller than whole house fans and move less air.
Their purpose is to ventilate the attic so it is not 140 degrees up
there; that puts less heat load on the house and also helps prolong
the life of your shingles. (A whole house fan also ventilates the
attic.) As some folks have mentioned, when the attic fan is running
you could also open up your attic access door and then it would suck
air out of the house, like a whole house fan (but probably weaker).
Attic fans usually have a temperature sensor that turns the fan on
automatically when the attic temperature reaches a certain level.

It seems to me there have been some posts to this group about people
having trouble with their attic-ventilation fans, that they stop
working and/or catch fire! Not sure whether that is a real issue or
just a fluke; you might try asking your insurance agent if they have
any statistics on that.

From your picture it looks like some parts of the house have little or
no attic space; those rooms might be unaffected by reducing the attic
temperature.

Also as a longer-term measure, you might consider planting some trees
in the yard to someday shade the house.

Cheers, -- H

In article , Heathcliff wrote:
Also I will say using a
whole house fan requires a little bit of operational savvy; you get a
nice breeze wherever you open a window, but you may have to prop the
door open in that room so it doesn't slam shut.

Solution: magnetic door stops. You open the door fully and a
magnet in the door stop keeps the door from moving.

They may be hard to find and/or expensive but are well
worth the effort.

I first saw them in several homes in China and thought
they were bloody terrific. They're easily available and
extremely cheap there so I brought a bunch home. I just
love these little suckers; best thing since sliced bread!

--
|~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~|
| Malcolm Hoar "The more I practice, the luckier I get". |
| Gary Player. |
| http://www.malch.com/ Shpx gur PQN. |
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~

On Jul 21, 7:35*am, "Chris (SilverUnicorn)"
wrote:
Hello again!

I ran a search, and I am nor confused than ever, plus I have some
other info from a contractor.

We have a 2 story, 2400 square foot "modern colonial" home (from what
I am told). LOL

Here is a picture of the house for reference:

http://farm1.static.flickr.com/205/4...09fe48e7_o.jpg

Our attic is insulated, with blown-in insulation. There is no storage
in the attic, and access is through a small access in our We have
ridge vents on the roof, with no other ventilation for the attic. We
were considering installing a whole house fan or maybe even an attic
fan. Are either of these a better option than the other? We would like
to lower the temperature of the house when it's cool outside (70-75
degrees) but warm inside (79-88 degrees).

I spoke with a friend who is a contractor. He seemed to thin an atic
fan without gable vents would not be effective, and that a whole house
fan would not give us the result we desire. Can anyone else inout on
this?

If you need additional info, please let me know.

Thank you,
Chris

There are a couple issues related to cooling your house.

(1) The house looks like it has a southern exposure, which means while
those skylights in what I presume is the living room will be great for
adding passive solar heat in the Winter, they are needlessly heating
the house in the Summer, unless you have shades/blinds over them or
the like.

(1a) Cover that arched window on the second floor! Sheesh - that's
adding all kinds of heat to that room (MBR?).

(1b) Consider awnings or some other form of shielding for windows that
receive prolonged Sun exposure. Blinds and shades are helpful, but
they don't stop the sunlight (in other words, heat) BEFORE it gets
inside the window.

(2) In our area of the country (I'm west and slightly south of you, in
western MD) the optimal insulation level in attic space is R50. Being
your house looks fairly new, I'm going to guess you have the paperwork
to check it out, or can contact the contractor who built it. The
reason R50 is helpful is not simply for holding heat in during cold
months, but for keeping the 120 degree heat of the attic in Summer
from penetrating to the upper floors of the interior.

(2a) Ventilate the living daylights out of the attic space in the
Summer, which means making sure you have enough soffit vents as others
have mentioned, and perhaps having a thermostatically-controlled vent
fan installed at one of the gable vents. While older models of attic
vent fans are noisy - I know from hearing them kick in at an
investment house I own - apparently there are newer models that are
whisper-quiet, as long as you don't mind paying a bit of a premium for
them (the same as with kitchen stove exhaust fans).

(3) Find an energy auditor to come to your home and do an assessment
to see where you can additionally save yourselves some coin on heating
and cooling costs. The Dept of Energy has links, and if you like there
is the Interfaith Coalition on Energy (www.interfaithenergy.com) right
there in Philly that is an faith-based group, which gives you a slight
modicum of reassurance that they're not in the business of energy
auditing to sell you products.

As far as the which-fan? question, I'm finding it darned-near
impossible to find a decently-constructed window-mounted fan that
could vent and allow me to cool off a couple rooms (my office, church
secretary, and library), so I would say you'll probably have better
luck finding a whole-house fan that vents into the attic than you
would finding a fan to mount in a window. Even though that means a
higher cost to install, what with having to have gable vents put in
and all...

On Jul 22, 3:24*pm, Heathcliff wrote:
On Jul 21, 6:35*am, "Chris (SilverUnicorn)"
wrote:





Hello again!

I ran a search, and I am nor confused than ever, plus I have some
other info from a contractor.

We have a 2 story, 2400 square foot "modern colonial" home (from what
I am told). LOL

Here is a picture of the house for reference:

http://farm1.static.flickr.com/205/4...09fe48e7_o.jpg

Our attic is insulated, with blown-in insulation. There is no storage
in the attic, and access is through a small access in our We have
ridge vents on the roof, with no other ventilation for the attic. We
were considering installing a whole house fan or maybe even an attic
fan. Are either of these a better option than the other? We would like
to lower the temperature of the house when it's cool outside (70-75
degrees) but warm inside (79-88 degrees).

I spoke with a friend who is a contractor. He seemed to thin an atic
fan without gable vents would not be effective, and that a whole house
fan would not give us the result we desire. Can anyone else inout on
this?

If you need additional info, please let me know.

Thank you,
Chris

Generally "whole house fan" refers to a fan mounted in the ceiling of
the top floor; it sucks air out of the house and blows it into the
attic. *For this to be effective, the attic must be well-ventilated;
i.e. there must be lots of ways air can then get from the attic to
outside. *Adequate venting for a whole house fan requires a little bit
of calculation: generally you need a vent area equal to the area of
the fan. *But for a vent with screen over it (which they all have),
you have to reduce the area by some percentage (because the screen
restricts the flow somewhat) to get the "effective area." *So if
installing a whole house fan, you would need to add up all the attic
vents and calculate their effective area, to see if you have enough
venting to match the area of the fan you want to install. *If not add
venting. *A competent contractor should be able to do all that. *I
just followed the instructions that came with my fan. * When the fan
operates, it sucks outside air into the house (must have windows
open), so it is ventilating the house, and is also ventilating the
attic since the house air gets blown into the attic and then from the
attic outside.

I installed whole-house fans in both houses I have owned; I like
them. *My climate is fairly similar to yours, at least in summer -
variably hot and humid. *As long as it cools off at night, I find the
fan a nice alternative to AC. *But as others have mentioned, you won't
necessarily save a lot of energy. *And some nights it will just not
cool off enough to make it comfortable. *Also *I will say using a
whole house fan requires a little bit of operational savvy; you get a
nice breeze wherever you open a window, but you may have to prop the
door open in that room so it doesn't slam shut. *It's not rocket
science but not completely foolproof. *Whole house fans usually come
with a timer switch so you can set it to run for, say, three hours,
then shut off (good when you're going to bed and don't want it to run
all night).

An "attic fan" or "attic ventilation fan" is mounted in the attic (in
a gable or the roof) and sucks air out of the attic and blows it
outside. *Again, the attic must be well vented for it to work right;
if there is not enough venting, some might have to be added. *Attic
fans are usually smaller than whole house fans and move less air.
Their purpose is to ventilate the attic so it is not 140 degrees up
there; that puts less heat load on the house and also helps prolong
the life of your shingles. (A whole house fan also ventilates the
attic.) As some folks have mentioned, when the attic fan is running
you could also open up your attic access door and then it would suck
air out of the house, like a whole house fan (but probably weaker).
Attic fans usually have a temperature sensor that turns the fan on
automatically when the attic temperature reaches a certain level.

It seems to me there have been some posts to this group about people
having trouble with their attic-ventilation fans, that they stop
working and/or catch fire! *Not sure whether that is a real issue or
just a fluke; you might try asking your insurance agent if they have
any statistics on that.

From your picture it looks like some parts of the house have little or
no attic space; those rooms might be unaffected by reducing the attic
temperature.

Also as a longer-term measure, you might consider planting some trees
in the yard to someday shade the house.

Cheers, -- H

I second the good advice given by Ed, Paul and Heathcliff. For the
WHF to be effective, you need periods where the outside air is around
70 or below and not excessively humid. In the Philly area, that
limits their usefulness to night usage in mostly the Spring and early
Fall. You could also use the WHF in summer if the AC has been off
and it's 85 inside, 75 outside, to drop the temp, then turn on the
AC, But if the humidity is too high, it's questionable if it's worth
it. If you have enough days where it works out for you, then it can
be worth it.

The attic fan is there to move air out of the attic so that it doesn't
get excessively hot. Before going with a fan, I'd make sure you have
maximum natural convection venting, ie ridge, soffit, gable etc. If
you can't get sufficient cooling that way, then a fan may be worth
it. However, either type of fan needs adequate attic ventilation to
be able to move the air volume.

on 7/23/2009 5:57 PM (ET) wrote the following:
On Jul 22, 3:24 pm, Heathcliff wrote:

On Jul 21, 6:35 am, "Chris (SilverUnicorn)"
wrote:






Hello again!

I ran a search, and I am nor confused than ever, plus I have some
other info from a contractor.

We have a 2 story, 2400 square foot "modern colonial" home (from what
I am told). LOL

Here is a picture of the house for reference:

http://farm1.static.flickr.com/205/4...09fe48e7_o.jpg

Our attic is insulated, with blown-in insulation. There is no storage
in the attic, and access is through a small access in our We have
ridge vents on the roof, with no other ventilation for the attic. We
were considering installing a whole house fan or maybe even an attic
fan. Are either of these a better option than the other? We would like
to lower the temperature of the house when it's cool outside (70-75
degrees) but warm inside (79-88 degrees).

I spoke with a friend who is a contractor. He seemed to thin an atic
fan without gable vents would not be effective, and that a whole house
fan would not give us the result we desire. Can anyone else inout on
this?

If you need additional info, please let me know.

Thank you,
Chris

Generally "whole house fan" refers to a fan mounted in the ceiling of
the top floor; it sucks air out of the house and blows it into the
attic. For this to be effective, the attic must be well-ventilated;
i.e. there must be lots of ways air can then get from the attic to
outside. Adequate venting for a whole house fan requires a little bit
of calculation: generally you need a vent area equal to the area of
the fan. But for a vent with screen over it (which they all have),
you have to reduce the area by some percentage (because the screen
restricts the flow somewhat) to get the "effective area." So if
installing a whole house fan, you would need to add up all the attic
vents and calculate their effective area, to see if you have enough
venting to match the area of the fan you want to install. If not add
venting. A competent contractor should be able to do all that. I
just followed the instructions that came with my fan. When the fan
operates, it sucks outside air into the house (must have windows
open), so it is ventilating the house, and is also ventilating the
attic since the house air gets blown into the attic and then from the
attic outside.

I installed whole-house fans in both houses I have owned; I like
them. My climate is fairly similar to yours, at least in summer -
variably hot and humid. As long as it cools off at night, I find the
fan a nice alternative to AC. But as others have mentioned, you won't
necessarily save a lot of energy. And some nights it will just not
cool off enough to make it comfortable. Also I will say using a
whole house fan requires a little bit of operational savvy; you get a
nice breeze wherever you open a window, but you may have to prop the
door open in that room so it doesn't slam shut. It's not rocket
science but not completely foolproof. Whole house fans usually come
with a timer switch so you can set it to run for, say, three hours,
then shut off (good when you're going to bed and don't want it to run
all night).

An "attic fan" or "attic ventilation fan" is mounted in the attic (in
a gable or the roof) and sucks air out of the attic and blows it
outside. Again, the attic must be well vented for it to work right;
if there is not enough venting, some might have to be added. Attic
fans are usually smaller than whole house fans and move less air.
Their purpose is to ventilate the attic so it is not 140 degrees up
there; that puts less heat load on the house and also helps prolong
the life of your shingles. (A whole house fan also ventilates the
attic.) As some folks have mentioned, when the attic fan is running
you could also open up your attic access door and then it would suck
air out of the house, like a whole house fan (but probably weaker).
Attic fans usually have a temperature sensor that turns the fan on
automatically when the attic temperature reaches a certain level.

It seems to me there have been some posts to this group about people
having trouble with their attic-ventilation fans, that they stop
working and/or catch fire! Not sure whether that is a real issue or
just a fluke; you might try asking your insurance agent if they have
any statistics on that.

From your picture it looks like some parts of the house have little or
no attic space; those rooms might be unaffected by reducing the attic
temperature.

Also as a longer-term measure, you might consider planting some trees
in the yard to someday shade the house.

Cheers, -- H


I second the good advice given by Ed, Paul and Heathcliff. For the
WHF to be effective, you need periods where the outside air is around
70 or below and not excessively humid. In the Philly area, that
limits their usefulness to night usage in mostly the Spring and early
Fall. You could also use the WHF in summer if the AC has been off
and it's 85 inside, 75 outside, to drop the temp, then turn on the
AC, But if the humidity is too high, it's questionable if it's worth
it. If you have enough days where it works out for you, then it can
be worth it.

The attic fan is there to move air out of the attic so that it doesn't
get excessively hot. Before going with a fan, I'd make sure you have
maximum natural convection venting, ie ridge, soffit, gable etc. If
you can't get sufficient cooling that way, then a fan may be worth
it. However, either type of fan needs adequate attic ventilation to
be able to move the air volume.


Another use for a whole house fan is to remove smoke or odors from the
house.
Burn something on the stove? Dog comes in after an encounter with a
skunk? Refinish a floor?

On Tue, 21 Jul 2009 04:35:15 -0700 (PDT), "Chris (SilverUnicorn)"
wrote:

Hello again!

I ran a search, and I am nor confused than ever, plus I have some
other info from a contractor.

We have a 2 story, 2400 square foot "modern colonial" home (from what
I am told). LOL

Here is a picture of the house for reference:

http://farm1.static.flickr.com/205/4...09fe48e7_o.jpg

Our attic is insulated, with blown-in insulation. There is no storage
in the attic, and access is through a small access in our We have
ridge vents on the roof, with no other ventilation for the attic. We
were considering installing a whole house fan or maybe even an attic
fan. Are either of these a better option than the other? We would like
to lower the temperature of the house when it's cool outside (70-75
degrees) but warm inside (79-88 degrees).

I spoke with a friend who is a contractor. He seemed to thin an atic
fan without gable vents would not be effective, and that a whole house
fan would not give us the result we desire. Can anyone else inout on
this?


If you need additional info, please let me know.

Thank you,
Chris

Listen to your friend. You might consider additional insulation.

Malcolm Hoar wrote:
: In article , Heathcliff wrote:
:Also I will say using a
:whole house fan requires a little bit of operational savvy; you get a
:nice breeze wherever you open a window, but you may have to prop the
:door open in that room so it doesn't slam shut.

: Solution: magnetic door stops. You open the door fully and a
: magnet in the door stop keeps the door from moving.

: They may be hard to find and/or expensive but are well
: worth the effort.

: I first saw them in several homes in China and thought
: they were bloody terrific. They're easily available and
: extremely cheap there so I brought a bunch home. I just
: love these little suckers; best thing since sliced bread!

They're available from Lee Valley.

-- Andy Barss

Kyle wrote:
: inside the window.

: (2) In our area of the country (I'm west and slightly south of you, in
: western MD) the optimal insulation level in attic space is R50. Being
: your house looks fairly new, I'm going to guess you have the paperwork
: to check it out, or can contact the contractor who built it. The
: reason R50 is helpful is not simply for holding heat in during cold
: months, but for keeping the 120 degree heat of the attic in Summer
: from penetrating to the upper floors of the interior.

: (2a) Ventilate the living daylights out of the attic space in the
: Summer, which means making sure you have enough soffit vents as others
: have mentioned, and perhaps having a thermostatically-controlled vent
: fan installed at one of the gable vents.

I'm in a similar situation as the OP, except for living in Tucson, AZ,
where the big problem is the attics getting extremely hot (160+
degrees) and radiating heat down into the living space. (I've come
to realize peaked roofs make utterly no sense in Arizona).

The consensus seems to be that getting the built-up air out is the key,
with air coming in from as low as possible (i.e. the soffet area),
exhausting it passively at or near the peak of the roof, and
making sure to have enough square feet of area in the inflow and
outflow.


But there's remarkably little information out there about products,
especially

a) soffet vents, other than cheap 16" x 8/10/12" perforatd metal,
and

b) ways of getting the inflow of air from the soffits up above
the attic floor and insulation (in an existing house).


I've been to three home centers and two roofing supply specialists,
all in Tucson, and no one has any range of alternatives for (a),
and none has a clue about (b). I was particularly
struck by the fact that the roofing supply guys really had no
idea there was even a problem in getting a clear pathway from
a soffet vent to the airspace up above the insulation. (In my house,
the roof slopes down enough that the sofets are about 3-4 feet
below the attic floor, and so 4-5 feet below the insulation
up there).

If anyone has any sources, even mail order, I'd appreciate the tip.
What I'm looking for for soffet vents is a continuous length
of peformated metal, that looks fairly nice, that could span
a 24" wide and 23 foor long area.

-- Andy Barss