Can anyone recommend any cheapo DIY ideas on how to exhaust heat from
an attic in a house?


unlike some of the folks here, who are forgetting a very important point,
let me remind you of something:

many places in the USA have high RADON levels
(RADON, a colorless, odorless gas, is the 2nd leading cause of lung cancer,
after smoking)

many of the solutions that are typically presented in this group involve
exhausting attic heat via a fan, turbine, etc.

most of these are "negative pressure" solutions, i.e. they suck air out in
order to exhaust the unwanted heat

this will cause RADON to be sucked IN to your home from the ground

I suggest the following two ideas which are at least as effective and will
not introduce any RADON:


suggestions for hot attics:

1. a positive pressure solution (i.e. fan blows into attic and out a vent,
rather than sucking air out and RADON in)

2. even better is a white roof, studies have shown that a white colored roof
is 7 times as efficient for eliminating attic heat than any vent, fan, or
turbine system


YFH

"Yeung Fun Ho" wrote in message
suggestions for hot attics:

1. a positive pressure solution (i.e. fan blows into attic and out a
vent,
rather than sucking air out and RADON in)

Agree with that. Attic venting shold be independent of the house unless you
are taling a whole house fan. OTOH, I'm not convinced radon is the threat
some make it out to be.


2. even better is a white roof, studies have shown that a white colored
roof
is 7 times as efficient for eliminating attic heat than any vent, fan, or
turbine system

Makes a lot of sense in hot climates, but in the winter, it is not a savings
here.

See here
http://www.hpa.org.uk/radiation/radon/index.htm

"Main Man" wrote in message
oups.com...
See here
http://www.hpa.org.uk/radiation/radon/index.htm


They state:
What Are the Effects of Radon?


Miners exposed to high radon levels have been found to run an
increased risk of lung cancer. Radon in the home also presents a risk, but
generally at a lower level.




Thus my earlier comment. I think it may be overblown in the home.

On Sat, 16 Jul 2005 03:04:24 GMT, in alt.home.repair DANGER:
RADON "Edwin Pawlowski" wrote:

They state:
What Are the Effects of Radon?


Miners exposed to high radon levels have been found to run an
increased risk of lung cancer. Radon in the home also presents a risk, but
generally at a lower level.

These studies were done in the 1950s and 1960s. Most (if not all) of
the miners where also heavy smokers. So many were smokers, that they
couldn't get a significant sample if they excluded smokers, so they
had to keep them in the sample. They compared the lung cancer rate of
the miners/smokers to the lung cancer rate of smokers-only. (They did
not consider the amount of smoking. I've never seen stats, but my
observations of miners as a group is that they are far heavier smokers
than the populaton at large.) The difference was very small, and many
researchers judged it to be statistically insignificant and the
studies non-conclusive.

That was judged to be an unacceptable and imprudent conclusion by
Health Physics community at the time, so a second committee was chosen
to review the results and *they* concluded that the differences while
indeed small, "might" be significant. That became the official party
line in the Health Physics community whose job and livelihood was
managing radiation risk. It just wouldn't do to find some natural
background radiation levels to be "safe" and without risk.

That has been the party line ever since but was pretty much ignored
and forgotten since the conclusions were so contrary human experience,
observation and common sense. Then in the 1990s when our culture was
running out of hysteria-of-the-month scares (global warming, nuclear
winter, no more water, etc.) this old bogeyman was resurrected.

It's perfect: you can't see it, can't feel it, can't smell it, can't
sense it, and can't find a single person that was effected by it. You
can only say that of 100,000 people exposed to it, *according to our
models and predictions* x-people surely must have been effected. What
the HP community does not say is that the predictive models were
designed *with the assumption* that there was an effect.

Well, a close relative of mine owns a radon testing service, so I hope
that in the future they require radon testing & mitigation as a
requirement of all home sales. If you can't get people to use common
sense, you might as well accommodate and profit from their fears :-)

--
To reply to me directly, remove the CLUTTER from my email address.

On Sat, 16 Jul 2005 07:18:14 -0500, Vic Dura
wrote:

On Sat, 16 Jul 2005 03:04:24 GMT, in alt.home.repair DANGER:
RADON "Edwin Pawlowski" wrote:

They state:
What Are the Effects of Radon?


Miners exposed to high radon levels have been found to run an
increased risk of lung cancer. Radon in the home also presents a risk, but
generally at a lower level.

These studies were done in the 1950s and 1960s. Most (if not all) of
the miners where also heavy smokers. So many were smokers, that they
couldn't get a significant sample if they excluded smokers, so they
had to keep them in the sample. They compared the lung cancer rate of
the miners/smokers to the lung cancer rate of smokers-only. (They did
not consider the amount of smoking. I've never seen stats, but my
observations of miners as a group is that they are far heavier smokers
than the populaton at large.) The difference was very small, and many
researchers judged it to be statistically insignificant and the
studies non-conclusive.

Where have you been? They didn't stop studying radon in the 60s. If
studies are non-conclusive, it means they (or the analyses) are
"non-conclusive," not that it's the end of the story. "Statistically
insignificant" can have as much to do with the design of a study as
with biological reality.

Do a simple literature search and take note of studies as recent as
this year; you're going to be surprized that the conclusions have
changed. The issue is not resolved by any means, particularly with
dosage, length of exposure (eg. lifetime risk of exposed children vs.
risk of adults exposed later in life), and degree of risk. But the
fact that it's a difficult issue to study doesn't mean that there is
no danger.

Sue(tm)
Lead me not into temptation... I can find it myself!

Yeung Fun Ho wrote:
Can anyone recommend any cheapo DIY ideas on how to exhaust heat from
an attic in a house?



unlike some of the folks here, who are forgetting a very important point,
let me remind you of something:

many places in the USA have high RADON levels
(RADON, a colorless, odorless gas, is the 2nd leading cause of lung cancer,
after smoking)

many of the solutions that are typically presented in this group involve
exhausting attic heat via a fan, turbine, etc.

True, but many places have no problem with radon.
Besides, the solution is generally simple and
inexpensive. (Of course there are "fixers" who
will insist that very expensive solutions are
necessary). Before anyone gets excited, check
with local health or other organizations for
radon in the local soils.


most of these are "negative pressure" solutions, i.e. they suck air out in
order to exhaust the unwanted heat

this will cause RADON to be sucked IN to your home from the ground

Almost any attic ventilation solution requires air
inlets and outlets. A fan that blows out requires
air inlets, either openings in the end gables or
openings in the soffits. As a result, very little
negative pressure will be developed. In any case,
negative pressure in the attic won't have any
effect on Radon in the house unless the attic is
tied to the rest of the house, the basement, or
the crawlspace and that isn't the case in most
houses (it may be the case with a whole house
fan). For radon to be a problem, radon has to
infiltrate the house from the soil. That may
occur from a basement or crawl space, but not from
an attic.

George,
I generally agree with you.
However, I hear from some some researchers that is is often the case
that there are connecting paths up through the house structure.

YFH might want to look at the Building Science Corporation web site.

TB

wrote:
George,
I generally agree with you.
However, I hear from some some researchers that is is often the case
that there are connecting paths up through the house structure.

YFH might want to look at the Building Science Corporation web site.

TB


True, with balloon framing used in old houses. I
would worry more about fires than Radon with such
construction.

Not true with modern house construction.

"George E. Cawthon" wrote in message
...
wrote:
George,
I generally agree with you.
However, I hear from some some researchers that is is often the case
that there are connecting paths up through the house structure.

YFH might want to look at the Building Science Corporation web site.

TB


True, with balloon framing used in old houses. I
would worry more about fires than Radon with such
construction.

Not true with modern house construction.


Holes for water vent, gas furnace and water heater chimneys go from basement
to roof.

In alt.hvac on Sat, 16 Jul 2005 11:14:42 -0500 "Mike Dobony"
posted:


"George E. Cawthon" wrote in message
...
wrote:
George,
I generally agree with you.
However, I hear from some some researchers that is is often the case
that there are connecting paths up through the house structure.

YFH might want to look at the Building Science Corporation web site.

TB


True, with balloon framing used in old houses. I
would worry more about fires than Radon with such
construction.

Not true with modern house construction.


Holes for water vent, gas furnace and water heater chimneys go from basement
to roof.

Yeah, in another thread I mentioned my forced air heating duct which
goes up my stack to the second. The oil furnace chimney is either in
the stack too or right next to it.

At the level of the first-floor ceiling or second floor floor, there
is a piece of plywood covering the stack, with holes for whatever goes
up there. I don't recall how well fitted the holes were to the duct
etc. Do all houses have the stack closed like this?

When I wanted to run another electric line, and phone lines and
burglar alarm lines, even with my 6 foot drill bit and a 12 inch
extension, it was hard to drill the hole.

Still, I don't think attic ventilation draws from the basement when
their are easier places to draw from, and even if there is radon in
the area, that doesn't mean it gets into the basement. There has to
be a crack in the foundation and in the right place.

Meirman
--
If emailing, please let me know whether
or not you are posting the same letter.
Change domain to erols.com, if necessary.

The important point is that radon is a danger to you or your pets
only if you breath it. If you are breathing it, then your risk level is
dependent upon the radon level in the air that you are breathing
and the length of time that you are exposed.

Pets, especially cats, are often at the greatest risk since in some
homes they spend a lot of time at ground level in the basement.
A person who spends much of the day in a basement home office
and a lot of free time watching his large screen basement TV may
also be at relatively great risk.

Radon is 9 times heavier than air and it tends to stay low in the
basement. Basement venting can greatly reduce radon levels.
Negative pressures in the house greatly increase radon infiltration
into the basement and subsequent radon movement up to the living
areas. Exhaust fans are obvious culprits. Air movement such as
that created by the furnace blower fan also increases the spread of
radon through the house. Cracks in basement foundations,
cracks in basement floors and openings such as sump pump pits
all increase infiltration.

Better than guessing, buy an inexpensive radon test kit, use it
correctly in your basement, and then send it to the lab. If the test
results indicate high radon levels, then buy a couple more test
kits and test your living areas. I have a friend whose basement
tested at 37 microcuries - a level considered rather dangerous.
But the upper levels of the house have acceptable levels of radon
and the family is relatively unconcerned since the basement is
just a place to house the furnace, water heater, washer, dryer
and a lot of junk.

They feel secure with just simple steps such as cracking open
a window when an exhaust fan is running, opening basement
windows on occasion for some basement cross ventilation, opening
living area windows briefly once in a while during the winter, etc.

Like cigarette smoking, radon can be very dangerous and can
present a greatly increased RISK of cancer. Like second-hand
smoke, radon dangers can be greatly exaggerated.

Gideon

And if there is no basement?

Gideon wrote:

The important point is that radon is a danger to you or your pets
only if you breath it. If you are breathing it, then your risk level is
dependent upon the radon level in the air that you are breathing
and the length of time that you are exposed.

Pets, especially cats, are often at the greatest risk since in some
homes they spend a lot of time at ground level in the basement.
A person who spends much of the day in a basement home office
and a lot of free time watching his large screen basement TV may
also be at relatively great risk.

Radon is 9 times heavier than air and it tends to stay low in the
basement. Basement venting can greatly reduce radon levels.
Negative pressures in the house greatly increase radon infiltration
into the basement and subsequent radon movement up to the living
areas. Exhaust fans are obvious culprits. Air movement such as
that created by the furnace blower fan also increases the spread of
radon through the house. Cracks in basement foundations,
cracks in basement floors and openings such as sump pump pits
all increase infiltration.

Better than guessing, buy an inexpensive radon test kit, use it
correctly in your basement, and then send it to the lab. If the test
results indicate high radon levels, then buy a couple more test
kits and test your living areas. I have a friend whose basement
tested at 37 microcuries - a level considered rather dangerous.
But the upper levels of the house have acceptable levels of radon
and the family is relatively unconcerned since the basement is
just a place to house the furnace, water heater, washer, dryer
and a lot of junk.

They feel secure with just simple steps such as cracking open
a window when an exhaust fan is running, opening basement
windows on occasion for some basement cross ventilation, opening
living area windows briefly once in a while during the winter, etc.

Like cigarette smoking, radon can be very dangerous and can
present a greatly increased RISK of cancer. Like second-hand
smoke, radon dangers can be greatly exaggerated.

Gideon

I can dig it, baby ......

On 16 Jul 2005 18:25:25 EDT, Vicki Szaszvari
wrote:

And if there is no basement?

Gideon wrote:

The important point is that radon is a danger to you or your pets
only if you breath it. If you are breathing it, then your risk level is
dependent upon the radon level in the air that you are breathing
and the length of time that you are exposed.

Pets, especially cats, are often at the greatest risk since in some
homes they spend a lot of time at ground level in the basement.
A person who spends much of the day in a basement home office
and a lot of free time watching his large screen basement TV may
also be at relatively great risk.

Radon is 9 times heavier than air and it tends to stay low in the
basement. Basement venting can greatly reduce radon levels.
Negative pressures in the house greatly increase radon infiltration
into the basement and subsequent radon movement up to the living
areas. Exhaust fans are obvious culprits. Air movement such as
that created by the furnace blower fan also increases the spread of
radon through the house. Cracks in basement foundations,
cracks in basement floors and openings such as sump pump pits
all increase infiltration.

Better than guessing, buy an inexpensive radon test kit, use it
correctly in your basement, and then send it to the lab. If the test
results indicate high radon levels, then buy a couple more test
kits and test your living areas. I have a friend whose basement
tested at 37 microcuries - a level considered rather dangerous.
But the upper levels of the house have acceptable levels of radon
and the family is relatively unconcerned since the basement is
just a place to house the furnace, water heater, washer, dryer
and a lot of junk.

They feel secure with just simple steps such as cracking open
a window when an exhaust fan is running, opening basement
windows on occasion for some basement cross ventilation, opening
living area windows briefly once in a while during the winter, etc.

Like cigarette smoking, radon can be very dangerous and can
present a greatly increased RISK of cancer. Like second-hand
smoke, radon dangers can be greatly exaggerated.

Gideon





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Buy a better house?

==================

Vicki Szaszvari wrote in message ...
And if there is no basement?

Haha! We have lots that are big enough here that we don't need to make
them more than one story.

Gideon wrote:

Buy a better house?

==================

Vicki Szaszvari wrote in message ...
And if there is no basement?

Yes it is IMPORTANT to make sur there are no open RETURN ducts in your
basement. These will casue negative pressure in the basment that can
pull radon in and distribute it in your home. Close off all RETURN
ducts in the basment and open one output duct in the basment to
pressurize the basmement a little. With the furnace blower running,
stand at the door to the basement with the door open a crack, if you
feel air being pulled into the basement from the upstairs, you have an
open return duct and need to close it.

Mark