I have been reading about everything I can find on radiant barriers,
but still have a few questions and concerns.

I am not talking new construction here, where radiant barrier can be
installed under the roof sheeting. I am talking about existing
homes, and then, primarily the spray on type.

Here is what I think I understand - -

Sprayed on radiant barrier will cut down 65 to 75 percent of the
sun's radiation, - but I really don't know how much cooler that
makes the attic.

Sprayed on radiant barrier effectiveness depends primarily on the
people who do the work. They can thin out the paint so it is much
less effective, they can spray it on to thin as well, and not get
the complete underside of the roof. Most homeowners would never
know they didn't get a good job. This is a major concern.

Dust on a radiant barrier surface decreases its effectiveness - the
more dust, the less effective. Although there generally is not a
lot of dust floating around in most attics, it can be stirred up
easily. For example, adding more insulation is a dusty procedure,
and if there is a previously installed radiant barrier, you will
decrease its effectiveness - to some varying extent.

There is a company that advertises radiant barriers for half price
(whatever that is) and free added insulation. If they spray their
cheap radiant barrier (about which I would have concern about how it
was mixed/thinned) and then add the insulation - instant dust.

This company has been advertising for months with some fantastic
deal or other and will only quote prices through an in home
salesman. I smell high pressure here.

Has anyone used this company? Has anyone used other companies to
spray a radiant barrier, and how satisfied are you?

I know I am asking a lot of questions, but I sure don't relish the
idea of getting ripped off. Thanks,

Bob-tx

On Mon, 15 Jun 2009 15:14:56 -0600, Bob-tx wrote:

I have been reading about everything I can find on radiant barriers,
but still have a few questions and concerns.

I am not talking new construction here, where radiant barrier can be
installed under the roof sheeting. I am talking about existing
homes, and then, primarily the spray on type.

Here is what I think I understand - -

Sprayed on radiant barrier will cut down 65 to 75 percent of the
sun's radiation, - but I really don't know how much cooler that
makes the attic.

Sprayed on radiant barrier effectiveness depends primarily on the
people who do the work. They can thin out the paint so it is much
less effective, they can spray it on to thin as well, and not get
the complete underside of the roof. Most homeowners would never
know they didn't get a good job. This is a major concern.

Dust on a radiant barrier surface decreases its effectiveness - the
more dust, the less effective. Although there generally is not a
lot of dust floating around in most attics, it can be stirred up
easily. For example, adding more insulation is a dusty procedure,
and if there is a previously installed radiant barrier, you will
decrease its effectiveness - to some varying extent.

There is a company that advertises radiant barriers for half price
(whatever that is) and free added insulation. If they spray their
cheap radiant barrier (about which I would have concern about how it
was mixed/thinned) and then add the insulation - instant dust.

This company has been advertising for months with some fantastic
deal or other and will only quote prices through an in home
salesman. I smell high pressure here.

Has anyone used this company? Has anyone used other companies to
spray a radiant barrier, and how satisfied are you?

I know I am asking a lot of questions, but I sure don't relish the
idea of getting ripped off. Thanks,

Bob-tx

Not all radiant barriers are sprayed on. Some are in sheets. I had it
done to a house we are rehabbing and the difference is amazing!

Bob-tx wrote:

I have been reading about everything I can find on radiant barriers,
but still have a few questions and concerns.

I am not talking new construction here, where radiant barrier can be
installed under the roof sheeting. I am talking about existing
homes, and then, primarily the spray on type.

Here is what I think I understand - -

Sprayed on radiant barrier will cut down 65 to 75 percent of the
sun's radiation, - but I really don't know how much cooler that
makes the attic.

Sprayed on radiant barrier effectiveness depends primarily on the
people who do the work. They can thin out the paint so it is much
less effective, they can spray it on to thin as well, and not get
the complete underside of the roof. Most homeowners would never
know they didn't get a good job. This is a major concern.

Dust on a radiant barrier surface decreases its effectiveness - the
more dust, the less effective. Although there generally is not a
lot of dust floating around in most attics, it can be stirred up
easily. For example, adding more insulation is a dusty procedure,
and if there is a previously installed radiant barrier, you will
decrease its effectiveness - to some varying extent.

There is a company that advertises radiant barriers for half price
(whatever that is) and free added insulation. If they spray their
cheap radiant barrier (about which I would have concern about how it
was mixed/thinned) and then add the insulation - instant dust.

This company has been advertising for months with some fantastic
deal or other and will only quote prices through an in home
salesman. I smell high pressure here.

Has anyone used this company? Has anyone used other companies to
spray a radiant barrier, and how satisfied are you?

I know I am asking a lot of questions, but I sure don't relish the
idea of getting ripped off. Thanks,

Bob-tx

Staple some mylar "space blankets" to the underside of your roof rafters
and be done with it.

On Jun 15, 4:25*pm, Mike Dobony wrote:
On Mon, 15 Jun 2009 15:14:56 -0600, Bob-tx wrote:
I have been reading about everything I can find on radiant barriers,
but still have a few questions and concerns.

I am not talking new construction here, where radiant barrier can be
installed under the roof sheeting. *I am talking about existing
homes, and then, primarily the spray on type.

Here is what I think I understand - -

Sprayed on radiant barrier will cut down 65 to 75 percent of the
sun's radiation, - but I really don't know how much cooler that
makes the attic.

Sprayed on radiant barrier effectiveness depends primarily on the
people who do the work. *They can thin out the paint so it is much
less effective, they can spray it on to thin as well, and not get
the complete underside of the roof. *Most homeowners would never
know they didn't get a good job. *This is a major concern.

Dust on a radiant barrier surface decreases its effectiveness - the
more dust, the less effective. *Although there generally is not a
lot of dust floating around in most attics, it can be stirred up
easily. *For example, adding more insulation is a dusty procedure,
and if there is a previously installed radiant barrier, you will
decrease its effectiveness - to some varying extent.

There is a company that advertises radiant barriers for half price
(whatever that is) and free added insulation. *If they spray their
cheap radiant barrier (about which I would have concern about how it
was mixed/thinned) and then add the insulation - instant dust.

This company has been advertising for months with some fantastic
deal or other and will only quote prices through an in home
salesman. *I smell high pressure here.

Has anyone used this company? * *Has anyone used other companies to
spray a radiant barrier, and how satisfied are you?

I know I am asking a lot of questions, but I sure don't relish the
idea of getting ripped off. * Thanks,

Bob-tx

Not all radiant barriers are sprayed on. *Some are in sheets. *I had it
done to a house we are rehabbing and the difference is amazing! *- Hide quoted text -

- Show quoted text -

How noticable was the difference, where was it used.

On Jun 15, 4:14*pm, "Bob-tx" wrote:
I have been reading about everything I can find on radiant barriers,
but still have a few questions and concerns.

If the laws of physics apply here, radiation impinging on the roof
will heat up the roof and sheathing as it passes through into the
attic. There it is met by the 'barrier, which is simply an aluminum
(paint or whatever) reflective surface. So it passes through the
sheathing and shingles a second time on its way out, thoroughly
cooking those materials. Soffit and ridge vents are installed to
permit air heated by such radiation to be escorted out the peak of the
roof. Maybe I missed something here, but it seems to me the net effect
would be to shorten the life span of the roofing quite a bit. Seems
more logical to get the radiation reflected away before penetrating
the shingles and sheathing, like using bright white shingles in the
first place, or painting the roof roof with aluminum paint, something
not very stylish in today's McMansions.
Over all, the proposed 'radiant barrier' might be like duct cleaning,
high priced and marginal unprovable benefits. Whatever, good luck.

Joe

Or builders foil, as said staple to underside of rafters, leave a small gap
between rows for vents, it's gotta breath.

Any radiant works MUCH better with an air gap. If applied to a surface,
conduction is the path of the heat

neutralexistence had written this in response to
http://www.thestuccocompany.com/main...rs-378805-.htm
:

Bob-tx wrote:


I have been reading about everything I can find on radiant barriers,
but still have a few questions and concerns.

I am not talking new construction here, where radiant barrier can be
installed under the roof sheeting. I am talking about existing
homes, and then, primarily the spray on type.

Here is what I think I understand - -

Sprayed on radiant barrier will cut down 65 to 75 percent of the
sun's radiation, - but I really don't know how much cooler that
makes the attic.

Sprayed on radiant barrier effectiveness depends primarily on the
people who do the work. They can thin out the paint so it is much
less effective, they can spray it on to thin as well, and not get
the complete underside of the roof. Most homeowners would never
know they didn't get a good job. This is a major concern.

Dust on a radiant barrier surface decreases its effectiveness - the
more dust, the less effective. Although there generally is not a
lot of dust floating around in most attics, it can be stirred up
easily. For example, adding more insulation is a dusty procedure,
and if there is a previously installed radiant barrier, you will
decrease its effectiveness - to some varying extent.

There is a company that advertises radiant barriers for half price
(whatever that is) and free added insulation. If they spray their
cheap radiant barrier (about which I would have concern about how it
was mixed/thinned) and then add the insulation - instant dust.

This company has been advertising for months with some fantastic
deal or other and will only quote prices through an in home
salesman. I smell high pressure here.

Has anyone used this company? Has anyone used other companies to
spray a radiant barrier, and how satisfied are you?

I know I am asking a lot of questions, but I sure don't relish the
idea of getting ripped off. Thanks,

Bob-tx


Hey Bob,

Let me see if I can shed some light on the questions. First of all the
paint type radiant barriers(term used loosely) have a "reflectivity" of no
more than 75% which "technically" is not, by definition, a radiant
barrier. A radiant barrier, technically defined, will have a reflectivity
of at least 95%.

I highly recommend a foil sheet type a
href="http://www.raflect.com"radiant barrier/a with a reflectivity
value of 97% to 98%. While the installation is a bit more challenging, the
results will be much better.

To address you question about dust and radiant barriers. While it is true
that dust can degrade the effectiveness of a radiant barrier, by
purchasing a double sided radiant barrier, you eliminate this problem.
Also, even if you do have some dust on the single sided radiant barrier,
it is still more effective then the paint type radiant barriers.

As far as installation, I highly recommend stapling the radiant barrier to
the bottom of your roof rafters. This will leave a gap (usually 5-1/2")
for air to move from your soffit vents up to your ridge vent, effectively
moving the hot reflected air up and out of your attic causing your whole
attic to be cooler.

Cooler attic means lower strain on your HVAC system causing lower energy
bills.

I also recommend getting a perforated type radiant barrier so you do not
run the risk of any condensation issues which could lead to structure rot
and/or mold.

Anyway, if you have any other questions let me know.

Adam

-------------------------------------
Get green Products:
http://www.neutralexistence.com



##-----------------------------------------------##
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Building Construction and Maintenance Forum
Web and RSS access to your favorite newsgroup -
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##-----------------------------------------------##

Sounds like good info. Thanks Bob-tx


"neutralexistence" wrote in
message m...
neutralexistence had written this in response to
http://www.thestuccocompany.com/main...rs-378805-.htm
:

Bob-tx wrote:


I have been reading about everything I can find on radiant
barriers,
but still have a few questions and concerns.

I am not talking new construction here, where radiant barrier can
be
installed under the roof sheeting. I am talking about existing
homes, and then, primarily the spray on type.

Here is what I think I understand - -

Sprayed on radiant barrier will cut down 65 to 75 percent of the
sun's radiation, - but I really don't know how much cooler that
makes the attic.

Sprayed on radiant barrier effectiveness depends primarily on the
people who do the work. They can thin out the paint so it is
much
less effective, they can spray it on to thin as well, and not get
the complete underside of the roof. Most homeowners would never
know they didn't get a good job. This is a major concern.

Dust on a radiant barrier surface decreases its effectiveness -
the
more dust, the less effective. Although there generally is not a
lot of dust floating around in most attics, it can be stirred up
easily. For example, adding more insulation is a dusty
procedure,
and if there is a previously installed radiant barrier, you will
decrease its effectiveness - to some varying extent.

There is a company that advertises radiant barriers for half
price
(whatever that is) and free added insulation. If they spray
their
cheap radiant barrier (about which I would have concern about how
it
was mixed/thinned) and then add the insulation - instant dust.

This company has been advertising for months with some fantastic
deal or other and will only quote prices through an in home
salesman. I smell high pressure here.

Has anyone used this company? Has anyone used other companies
to
spray a radiant barrier, and how satisfied are you?

I know I am asking a lot of questions, but I sure don't relish
the
idea of getting ripped off. Thanks,

Bob-tx


Hey Bob,

Let me see if I can shed some light on the questions. First of all
the
paint type radiant barriers(term used loosely) have a
"reflectivity" of no
more than 75% which "technically" is not, by definition, a radiant
barrier. A radiant barrier, technically defined, will have a
reflectivity
of at least 95%.

I highly recommend a foil sheet type a
href="http://www.raflect.com"radiant barrier/a with a
reflectivity
value of 97% to 98%. While the installation is a bit more
challenging, the
results will be much better.

To address you question about dust and radiant barriers. While it
is true
that dust can degrade the effectiveness of a radiant barrier, by
purchasing a double sided radiant barrier, you eliminate this
problem.
Also, even if you do have some dust on the single sided radiant
barrier,
it is still more effective then the paint type radiant barriers.

As far as installation, I highly recommend stapling the radiant
barrier to
the bottom of your roof rafters. This will leave a gap (usually
5-1/2")
for air to move from your soffit vents up to your ridge vent,
effectively
moving the hot reflected air up and out of your attic causing your
whole
attic to be cooler.

Cooler attic means lower strain on your HVAC system causing lower
energy
bills.

I also recommend getting a perforated type radiant barrier so you
do not
run the risk of any condensation issues which could lead to
structure rot
and/or mold.

Anyway, if you have any other questions let me know.

Adam

-------------------------------------
Get green Products:
http://www.neutralexistence.com



##-----------------------------------------------##
Delivered via http://www.thestuccocompany.com/
Building Construction and Maintenance Forum
Web and RSS access to your favorite newsgroup -
alt.home.repair - 359333 messages and counting!
##-----------------------------------------------##

I'm going to resurrect this one.

It's damned hot here in Central Texas and I bought radiant barrier
sheeting to install in the attic. Problem is, I can't get to most of
the places where it would need to go. Why not install it ON TOP OF
THE SHINGLES? It would be kind of temporary but, to get us through
the summer, seems like it would be a good idea. I was thinking of
Styrofoam sheets that I could staple the sheeting to and then install
these on the roof with some space between them and the shingles. I
don't mind crawling around on the roof but I can't get myself in all
the attic spaces.

Also, I Googled radiant barrier paint and sure enough there is such a
thing. I was thinking of repainting the outside of my house.

In reality, all this would go on the back. The front has nice big
shade trees and it's very protected.

Was toying with the idea of installing a sprinkler system on the roof
to cool it down during the day...?

Brad

On Jun 16, 2:02*pm,
(neutralexistence) wrote:
neutralexistence had written this in response tohttp://www.thestuccocompany.com/maintenance/Let-s-talk-radiant-Barrie...
*:



Bob-tx wrote:
I have been reading about everything I can find onradiantbarriers,
but still have a few questions and concerns.
I am not talking new construction here, whereradiantbarrier can be
installed under the roof sheeting. *I am talking about existing
homes, and then, primarily the spray on type.
Here is what I think I understand - -
Sprayed onradiantbarrier will cut down 65 to 75 percent of the
sun's radiation, - but I really don't know how much cooler that
makes the attic.
Sprayed onradiantbarrier effectiveness depends primarily on the
people who do the work. *They can thin out the paint so it is much
less effective, they can spray it on to thin as well, and not get
the complete underside of the roof. *Most homeowners would never
know they didn't get a good job. *This is a major concern.
Dust on aradiantbarrier surface decreases its effectiveness - the
more dust, the less effective. *Although there generally is not a
lot of dust floating around in most attics, it can be stirred up
easily. *For example, adding more insulation is a dusty procedure,
and if there is a previously installedradiantbarrier, you will
decrease its effectiveness - to some varying extent.
There is a company that advertisesradiantbarriers for half price
(whatever that is) and free added insulation. *If they spray their
cheapradiantbarrier (about which I would have concern about how it
was mixed/thinned) and then add the insulation - instant dust.
This company has been advertising for months with some fantastic
deal or other and will only quote prices through an in home
salesman. *I smell high pressure here.
Has anyone used this company? * *Has anyone used other companies to
spray aradiantbarrier, and how satisfied are you?
I know I am asking a lot of questions, but I sure don't relish the
idea of getting ripped off. * Thanks,
Bob-tx

Hey Bob,

Let me see if I can shed some light on the questions. First of all the
paint typeradiantbarriers(term used loosely) have a "reflectivity" of no
more than 75% which "technically" is not, by definition, aradiant
barrier. Aradiantbarrier, technically defined, will have a reflectivity
of at least 95%.

I highly recommend a foil sheet type a
href="http://www.raflect.com"radiantbarrier/a with a reflectivity
value of 97% to 98%. While the installation is a bit more challenging, the
results will be much better.

To address you question about dust andradiantbarriers. While it is true
that dust can degrade the effectiveness of aradiantbarrier, by
purchasing a double sidedradiantbarrier, you eliminate this problem.
Also, even if you do have some dust on the single sidedradiantbarrier,
it is still more effective then the paint typeradiantbarriers.

As far as installation, I highly recommend stapling theradiantbarrier to
the bottom of your roof rafters. This will leave a gap (usually 5-1/2")
for air to move from your soffit vents up to your ridge vent, effectively
moving the hot reflected air up and out of your attic causing your whole
attic to be cooler.

Cooler attic means lower strain on your HVAC system causing lower energy
bills.

I also recommend getting a perforated typeradiantbarrier so you do not
run the risk of any condensation issues which could lead to structure rot
and/or mold.

Anyway, if you have any other questions let me know.

Adam

-------------------------------------
Get green Products:http://www.neutralexistence.com

##-----------------------------------------------##
Delivered via *http://www.thestuccocompany.com/
Building Construction and Maintenance Forum
Web and RSS access to your favorite newsgroup -
alt.home.repair - 359333 messages and counting!
##-----------------------------------------------##