I'm getting a new roof on my house. I'm considering changing to brown
shingles (Owens Corning Desert Tan) from white shingles.

If anyone here has any experience about increased air conditioning costs
after going to a darker roof, I would like know how much your bill went up
(or didn't).

Particulars would be most helpful, such as climate, and how well the attic
was insulated.

My own particulars: Louisville KY, ranch house, low pitched hip roof,
poorly insulated attic. Air conditioner ducts do not pass through attic.
House gets a fair amount of shade from trees located on East, South, and
West sides. But they are Maples, and I don't want to assume they will last
the next 30 years.

--
Tony Sivori

On 5/25/2012 11:46 AM, Tony Sivori wrote:
I'm getting a new roof on my house. I'm considering changing to brown
shingles (Owens Corning Desert Tan) from white shingles.

If anyone here has any experience about increased air conditioning costs
after going to a darker roof, I would like know how much your bill went up
(or didn't).

Particulars would be most helpful, such as climate, and how well the attic
was insulated.

My own particulars: Louisville KY, ranch house, low pitched hip roof,
poorly insulated attic. Air conditioner ducts do not pass through attic.
House gets a fair amount of shade from trees located on East, South, and
West sides. But they are Maples, and I don't want to assume they will last
the next 30 years.


Improving attic insulation and ventilation will have a much bigger
effect on your heating and air conditioning costs. My new house is
over twice the size of my old house. The winter heating and summer
cooling costs are lower in the new house than in the old house.

The attic in the old house was like an oven in the summer. The attic
temperature in the new house is barely warmer than outside. The attic
is so well ventilated you can feel a breeze moving through it.

LdB

"Tony Sivori" wrote in message
news
I'm getting a new roof on my house. I'm considering changing to brown
shingles (Owens Corning Desert Tan) from white shingles.

If anyone here has any experience about increased air conditioning costs
after going to a darker roof, I would like know how much your bill went
up
(or didn't).

Particulars would be most helpful, such as climate, and how well the
attic
was insulated.

My own particulars: Louisville KY, ranch house, low pitched hip roof,
poorly insulated attic. Air conditioner ducts do not pass through attic.
House gets a fair amount of shade from trees located on East, South, and
West sides. But they are Maples, and I don't want to assume they will
last
the next 30 years.

--
Tony Sivori

I was a roof rat for 20+ years, so I have a bit of experience with them.
First & foremost, decide on the color/style based on curb appeal. It is
said 40% of the curb appeal on a home is based on roof color & style. Don't
count on the color to keep your home cool, if you must upgrade your
insulation factors & venting, do so. The granules used on shingles is based
on opacity for UV rays. Most manufacturers use a quality granule. Choose
the color based on your liking, not someone else's. For example, I always
despised the desert tan & white, it always looked _cheap_ to me, but then
it's not my home. Consider a style, which would fit well, most
architectural shingles add to value over the standard 3 tab. Also consider
a shingle, which has mold inhibitors added at the manufacturer, the price
difference isn't that much considering a roof is an investment. Also,
consider a color, which will be around for awhile, don't go with a _new_
color or fad. Having a bundle or 2 shingles as extras isn't a bad idea,
but having to keep a square or 2 around takes up space.

On May 25, 2:13*pm, "Gomba" wrote:
"Tony Sivori" wrote in message

news








I'm getting a new roof on my house. I'm considering changing to brown
shingles (Owens Corning Desert Tan) from white shingles.

If anyone here has any experience about increased air conditioning costs
after going to a darker roof, I would like know how much your bill went
up
(or didn't).

Particulars would be most helpful, such as climate, and how well the
attic
was insulated.

My own particulars: Louisville KY, ranch house, low pitched hip roof,
poorly insulated attic. Air conditioner ducts do not pass through attic..
House gets a fair amount of shade from trees located on East, South, and
West sides. But they are Maples, and I don't want to assume they will
last
the next 30 years.

--
Tony Sivori

I was a roof rat for 20+ years, so I have a bit of experience with them.
First & foremost, decide on the color/style based on curb appeal. It is
said 40% of the curb appeal on a home is based on roof color & style. Don't
count on the color to keep your home cool, if you must upgrade your
insulation factors & venting, do so. The granules used on shingles is based
on opacity for UV rays. Most manufacturers use a quality granule. Choose
the color based on your liking, not someone else's. For example, I always
despised the desert tan & white, it always looked _cheap_ to me, *but then
it's not my home. Consider a style, which would fit well, most
architectural shingles add to value over the standard 3 tab. Also consider
a shingle, which has mold inhibitors added at the manufacturer, the price
difference isn't that much considering a roof is an investment. Also,
consider a color, which will be around for awhile, don't go with a _new_
color or fad. *Having a bundle or 2 shingles as extras isn't a bad idea,
but having to keep a square or 2 around takes up space.


My house was built in 1983 and had a concrete tile roof on it. I am
in the Tampa Bay area - and after Andrew in 1992 the codes for roofs
changed. When it came time to replace mine I could not afford a tile
roof (each piece must be nailed at all four corners). Anyway, I got
GAF - good for up to 120mph winds - light brown color. There were
vents at each end of my house - in the attic - and they were boarded
up. The new roof has a ridge vent.... the costs of a/c hasn't changed
any because of the roof being different. I used to have a man come by
once a year and spray the tile roof so I wouldn't get mildew or mold
-- and I don't need to do that anymore. At least not yet ... the
papers that came with the roof said it was treated for fungus and all
that. So far it's working....had it since 2007.

On May 25, 6:49*pm, Dottie wrote:
On May 25, 2:13*pm, "Gomba" wrote:





"Tony Sivori" wrote in message

news

I'm getting a new roof on my house. I'm considering changing to brown
shingles (Owens Corning Desert Tan) from white shingles.

If anyone here has any experience about increased air conditioning costs
after going to a darker roof, I would like know how much your bill went
up
(or didn't).

Particulars would be most helpful, such as climate, and how well the
attic
was insulated.

My own particulars: Louisville KY, ranch house, low pitched hip roof,
poorly insulated attic. Air conditioner ducts do not pass through attic.
House gets a fair amount of shade from trees located on East, South, and
West sides. But they are Maples, and I don't want to assume they will
last
the next 30 years.

--
Tony Sivori

I was a roof rat for 20+ years, so I have a bit of experience with them..
First & foremost, decide on the color/style based on curb appeal. It is
said 40% of the curb appeal on a home is based on roof color & style. Don't
count on the color to keep your home cool, if you must upgrade your
insulation factors & venting, do so. The granules used on shingles is based
on opacity for UV rays. Most manufacturers use a quality granule. Choose
the color based on your liking, not someone else's. For example, I always
despised the desert tan & white, it always looked _cheap_ to me, *but then
it's not my home. Consider a style, which would fit well, most
architectural shingles add to value over the standard 3 tab. Also consider
a shingle, which has mold inhibitors added at the manufacturer, the price
difference isn't that much considering a roof is an investment. Also,
consider a color, which will be around for awhile, don't go with a _new_
color or fad. *Having a bundle or 2 shingles as extras isn't a bad idea,
but having to keep a square or 2 around takes up space.

My house was built in 1983 and had a concrete tile roof on it. *I am
in the Tampa Bay area - and after Andrew in 1992 the codes for roofs
changed. *When it came time to replace mine I could not afford a tile
roof (each piece must be nailed at all four corners). *Anyway, I got
GAF - good for up to 120mph winds - *light brown color. *There were
vents at each end of my house - in the attic - and they were boarded
up. *The new roof has a ridge vent.... the costs of a/c hasn't changed
any because of the roof being different. *I used to have a man come by
once a year and spray the tile roof so I wouldn't get mildew or mold
-- and I don't need to do that anymore. *At least not yet ... the
papers that came with the roof said it was treated for fungus and all
that. *So far it's working....had it since 2007.

If you had gone with a white roof your AC bill may have gone down....

On May 25, 11:46*am, Tony Sivori wrote:
I'm getting a new roof on my house. I'm considering changing to brown
shingles (Owens Corning Desert Tan) from white shingles.

If anyone here has any experience about increased air conditioning costs
after going to a darker roof, I would like know how much your bill went up
(or didn't).

Particulars would be most helpful, such as climate, and how well the attic
was insulated.

My own particulars: Louisville KY, ranch house, low pitched hip roof,
poorly insulated attic. Air conditioner ducts do not pass through attic.
House gets a fair amount of shade from trees located on East, South, and
West sides. But they are Maples, and I don't want to assume they will last
the next 30 years.

--
Tony Sivori

I would go for a light tan or grey color, depending on house color

On Fri, 25 May 2012 12:46:10 -0400, Tony Sivori
wrote:



My own particulars: Louisville KY, ranch house, low pitched hip roof,
poorly insulated attic.

Forget everything else. Insulate the attic. Cheap and you can do it
yourself. The savings there is far more than the difference in roof
color.

Ed Pawlowski wrote:

On Fri, 25 May 2012 12:46:10 -0400, Tony Sivori
wrote:



My own particulars: Louisville KY, ranch house, low pitched hip roof,
poorly insulated attic.

Forget everything else. Insulate the attic. Cheap and you can do it
yourself. The savings there is far more than the difference in roof
color.

No two ways about, I do need and would benefit from more attic insulation.
But to get to the recommended R value it will run about $700 even as a DIY
job, so I don't consider it especially cheap.

Doing the math if it were to cut my total energy usage 20% (I doubt if I
would save that much), it would take 7.3 years to break even on the $700
up front cost.

So I would like to do it someday, but for now it is not at the top of my
priority list.

--
Tony Sivori

Gomba wrote:


"Tony Sivori" wrote in message
news
I'm getting a new roof on my house. I'm considering changing to brown
shingles (Owens Corning Desert Tan) from white shingles.

If anyone here has any experience about increased air conditioning
costs after going to a darker roof, I would like know how much your
bill went up (or didn't).


I was a roof rat for 20+ years, so I have a bit of experience with them.
First & foremost, decide on the color/style based on curb appeal. It is
said 40% of the curb appeal on a home is based on roof color & style.
Don't count on the color to keep your home cool, if you must upgrade
your insulation factors & venting, do so.

I'm thinking about adding a ridge vent.

The granules used on shingles is
based on opacity for UV rays. Most manufacturers use a quality granule.
Choose the color based on your liking, not someone else's. For example,
I always despised the desert tan & white, it always looked _cheap_ to
me, but then it's not my home.

I don't like the look of the white either. I do like the Desert Tan (in
the eye of the beholder, I guess), but not so much that I would want my
cooling bill to be $10 or $20 higher every summer month.

Consider a style, which would fit well, most architectural shingles add
to value over the standard 3 tab.

This is a hail damage insurance job, so I can afford some out of pocket to
upgrade to a better shingle than the 3 tabs that are now in place.

Also consider a shingle, which has mold inhibitors added at the
manufacturer, the price difference isn't that much considering a roof is
an investment. Also, consider a color, which will be around for awhile,
don't go with a _new_ color or fad. Having a bundle or 2 shingles as
extras isn't a bad idea, but having to keep a square or 2 around takes
up space.

Do you have any opinion about Owens Corning Oakridge versus GAF
Timberline?

--
Tony Sivori

LdB wrote:
Improving attic insulation and ventilation will have a much bigger effect
on your heating and air conditioning costs. My new house is over twice the
size of my old house. The winter heating and summer cooling costs are
lower in the new house than in the old house.

The attic in the old house was like an oven in the summer.

That is what my miserable little scuttle is like, I'd guess it is 120 up
there mid-day in the summer.

The attic temperature in the new house is barely warmer than outside.
The attic is so well ventilated you can feel a breeze moving through it.

LdB

--
Tony Sivori

Kentucky?? I could see roof color being a factor in Florida - or the Caribbean or Equatorial Africa, but not in a temperate inland area like Kentucky.. Best just to insulate that attic floor(yes insulation does keep from transferring into rooms below it in summer), and either install proper ridge vent or end vents. Remember the only purpose of a roof is to keep moisture/wind of the lived in part of a home - unless the attic is to be lived in as well. And do not insulate between the roof rafters, unless the last part of my last sentence applies.

Tony Sivori wrote:

If anyone here has any experience about increased air conditioning
costs after going to a darker roof, I would like know how much your
bill went up (or didn't).

Executive summary:

1) proper venting and a ****-load of insulation can (or will) make
shingle-color irrelavent in terms of heat-load to the home's A/C system

2) consider using a radiant barrier underlayment under the shingles -
regardless of shingle color

3) I suspect that shingle color DOES play a role in shingle life-span
(darker shingles will get hotter, probably will have shorter life)

4) I've paid more attention to the homes in my area (great-lakes area)
with light-colored asphalt shingles, many of which have trees nearby,
and I see little to no evidence of staining / discoloration. The extent
to which this staining is assumed to happen might be over-estimated.


A study (reproduced at the very bottom of this post) gives these
conclusions:

- The greatest influence on roof temperature is geographic location.

- The direction a roof faces has the second greatest influence on
average roof temperature

- The color of roofing materials influences the mean temperature
of a roof system slightly less than direction

- Ventilating the area under a roof deck reduces the average
temperature 0.5 degrees Celsius (about one-third the influence
of the direction or color and one-thirty-sixth the influence of
geographic location). Even with wind assistance, ventilation
reduces average roof temperature about half as much as using
white rather than black shingles.

- Within the ranges studied, slope has the least influence on average
shingle temperature.

Remember, that study is looking at roof temperature, not ambient air
temperature inside the attic. They conclude with this statement:

"Many shingle manufacturers provide warranted products that are
widely distributed and are of many colors and exclude from
warranties those shingles installed on unventilated decks. This
exclusion has no justification; the variations in geography,
direction and shingle color have greater influences on average
temperature than the degree of ventilation."

The first study that I'm reproducing (immediately below) is focused on
attic air temperature and household heat-load.

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

Monitored Summer Peak Attic Air Temperatures in Florida Residences
http://www.fsec.ucf.edu/en/publicati...6-98/index.htm

The field data was from a variety of residential monitoring projects
which were classified according to intrinsic differences in roofing
configurations and characteristics. The sites were occupied homes spread
around the state of Florida. There were a variety of different roofing
construction types, roof colors and ventilation configurations.

The ambient air temperature was obtained at each site by thermocouple
located inside a shielded exterior enclosure at a 3-4m (10-12 foot)
height. The summer 15-minute data from each site were sorted by the
average ambient air temperature into the top 2.5% of the observations of
the highest temperature. Within this limited group of observations, the
average outside air temperature, attic air temperature and the
coincident difference was reported.

Attic air temperatures vary considerably depending on roofing type,
color and ventilation.

It is worth noting that light gray or "white" asphalt shingles have a
measured solar absorptance of approximately 75% as opposed to true
reflective roofing systems which have absorptances less than 30% (Parker
et al., 1993B). Dark gray shingles have a solar absorptance of about
90%.

http://www.fsec.ucf.edu/en/publicati...es/attic-5.gif

Figure 5. Influence of asphalt shingle color on measured average attic
air temperature at two adjacent Homestead, Florida sites (HO2 and HO5)
during the summer of 1996.

Conclusions

Although the 21-house data set is not large enough to comprise a
statistical sample, it does suggest some important influences on summer
attic design temperatures in Florida. Light roof colors, deck-mounted
radiant barriers, added attic ventilation and tile roof construction
were all shown to reduce peak attic air temperatures. A simple
characterization of the collected data would be as follows:

Table 6
Comparison of Coincident Attic to Ambient Design Temperature Difference

Case / Attic Design Temperature

Shingle roof soffit vent only / Ambient + 35F (19.4C)
Shingle roof soffit and ridge venting / Ambient + 22F (12.2C)
Shingle roof Radiant Barrier soffit vent only / Ambient + 25F (13.9C)
Tile roof / Ambient +10F (5.6C)
White roof / Ambient -1.5F (0.8C)

A simple calculation illustrates the importance of controlling the peak
attic air temperatures measured in this study. As example, consider a
residence on a a peak summer day at 95F served by a three ton cooling
system with a sensible capacity of 27,000 Btu/hr and an EER of 9.0
Btu/W. The assumed residence has a 1,800 square foot ceiling with R-30
attic insulation.

Supply ducts typically comprise a combined area of ~25% of the gross
floor area (see Gu et al. 1997, Appendix G, and Jump and Modera, 1994),
but are only insulated to R-4. With the peak attic temperatures for a
shingle roof with poor ventilation estimated at 130F, and 75 maintained
inside, a UA dT calculation shows a ceiling heat gain of 3,300 Btu/hr.
With R-4 ducts in the attic and a 57 air conditioner supply temperature,
the heat gain to the duct system is 8,212 Btu/hr if the cooling system
ran the full hour under design conditions-- more than twice the ceiling
flux. However, the magnitude of both ceiling and duct heat gain is 43%
of the air conditioner's design sensible cooling load. Thus, attic heat
to ceiling and attic to duct heat gains are a major portion of the
design cooling load for residences.

In the example the attic related gains are also responsible for a 1.28
kW increase in peak air conditioning electric demand. As a contrast,
with a white roof system, the estimated attic air temperature would be
93.5F, with a total ceiling and duct heat transfer rate of 5220 Btu-- a
reduction of 6,300 Btu/hr and a drop in electrical demand of 700 W if
the system was at design capacity with the dark roof.
==================

See also:

http://www.newton.dep.anl.gov/askasc...9/eng99520.htm

http://findlayroofing.com/blog/roof-...e-temperature/


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

(the following material does not consider shingle-color in terms of
imacting shingle-lifespan)

http://www.findlayroofingnc.com/reso...me-temperature

Shingles Follow The Rules - Black is Hotter Than White

No one questions if black shingles get hotter than white shingles, but
many people have wondered what the temperature difference really is.
Shingle manufacturers have been especially interested in answering this
question, and many have performed tests to determine the number.

Their test conditions and results vary, but the temperature difference
between a white and black shingle, when exposed to the same amount of
sunlight, is generally stated to be from 20° to 40° F.

Without a doubt, 40° F is a big difference. But keep in mind that this
number is likely taken from a small number of specimens, and the testing
was done under very specific conditions. The point is, these numbers
aren't good enough to suggest you race out to buy all the white shingles
in town today.

Every Shingle Color Stays Cool With Good Roof Ventilation

Test data is useful information to have, but the most important data
comes from actual rooftops and homes. And the real rooftop data clearly
shows that shingle color is a small player when it comes to shingle
temperature.

Any professional roofing contractor will tell you that choosing a
shingle color should be based on personal preference more than on
temperature concerns. Proper roof ventilation is the real key to keeping
your shingles cool and making them last as long as possible. There are
countless dark-colored roofs across the country that are still going
strong after 15 years, to prove the point.

What About The Temperature Inside My North Carolina House?

With good roof ventilation, the impact of shingle color on roof and
attic temperatures becomes somewhat insignificant. The presence of
insulation in an attic makes shingle color practically irrelevant, in
terms of interior room temperatures.

Put another way, there is no need to worry about temperature effects
when choosing a shingle color for your home. Instead, you should work
with your roofing contractor to make sure that your roof has the ideal
amount of ventilation.

By installing the proper combination of ridge and soffit vents, for
example, your can keep your North Carolina roof cool during even the
hottest of days. A cool roof keeps your shingles cool, and allows them
to achieve their longest possible life. At the same time, you will be
keeping your home cooler all summer long.

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

What's the value of ventilation?

A study of asphalt shingles demonstrates ventilation may not be as
important as other variables

http://www.professionalroofing.net/a...2/feature2.asp

The topic of asphalt shingles splitting and cracking has received much
attention lately. Asphalt fiberglass shingles have been experiencing
vertical splits, as well as horizontal splits in exposed tabs. These
dislocations, called thermal splits, are the subject of a great deal of
litigation, including class-action lawsuits. The splits are not
associated with quality of installation. Rather, the splits occur in
shingles where self-sealing adhesive firmly adheres the shingle tabs and
a shingle's tear strength is low or inadequate to withstand a thermally
or mechanically induced load.

Whenever asphalt fiberglass shingle manufacturers are faced with
thermal-splitting problems, one excuse they usually offer is that the
area under a roof deck was not ventilated properly.

This excuse is offered not because there is any evidence of a
cause-and-effect link between thermal splitting and ventilation but
because shingle warranties (all the shingle warranties listed in NRCA's
2002-03 Steep-slope Roofing Materials Guide) specifically exclude
warranties in the case of "inadequate attic ventilation." This is based
on the premise that shingles applied to decks over unventilated attics
will be unacceptably hotter than shingles applied to decks over properly
ventilated attics and have significantly shortened service lives as a
result of the increased temperature.

Lawyers say impractical or unreasonable contract or warranty provisions
may not be supported by court decisions. The following information
reveals results from a study we conducted that investigated the
reasonableness of the "inadequate attic ventilation" exclusion in
warranties.

Some parameters that can influence roof temperature are geographic
location, color, exposure orientation, slope and degree of attic
ventilation. We report the means (averages) of the maximum and average
annual temperatures of the roofing materials for each combination of
these parameters.

(lots of material describing a multi-city study not reproduced here)

Conclusions

The following conclusions are based on data from our numerical model:

* The greatest influence on roof temperature is geographic location. The
mean roof temperatures for Miami and Green Bay, Wis., for example,
differ by 18 degrees Celsius.

* The direction a roof faces has the second greatest influence on
average roof temperature (in excess of 1.44 degrees Celsius in the east
through south-to-west range studied, but the real difference is greater
because other directions, such as north, will be cooler).

* The color of roofing materials influences the mean temperature of a
roof system slightly less than direction (1.45 degrees Celsius average
for these parameters).

* Ventilating the area under a roof deck reduces the average temperature
0.5 degrees Celsius (about one-third the influence of the direction or
color and one-thirty-sixth the influence of geographic location). Even
with wind assistance, ventilation reduces average roof temperature about
half as much as using white rather than black shingles.

* Within the ranges studied, slope has the least influence on average
shingle temperature.

Many shingle manufacturers provide warranted products that are widely
distributed and are of many colors and exclude from warranties those
shingles installed on unventilated decks. This exclusion has no
justification; the variations in geography, direction and shingle color
have greater influences on average temperature than the degree of
ventilation.

However, ventilation should be recommended to remove the small quantity
of moisture in a roof system; it can prolong the life of a wood deck
even if it does not extend the life of shingles.

Carl G. Cash is a principal with Simpson, Gumpertz & Heger Inc.,
Arlington, Mass., and Edward G. Lyon is a senior staff engineer with
Simpson, Gumpertz & Heger.

On 5/26/2012 12:11 AM, Tony Sivori wrote:
Ed Pawlowski wrote:

On Fri, 25 May 2012 12:46:10 -0400, Tony
wrote:



My own particulars: Louisville KY, ranch house, low pitched hip roof,
poorly insulated attic.

Forget everything else. Insulate the attic. Cheap and you can do it
yourself. The savings there is far more than the difference in roof
color.

No two ways about, I do need and would benefit from more attic insulation.
But to get to the recommended R value it will run about $700 even as a DIY
job, so I don't consider it especially cheap.

Doing the math if it were to cut my total energy usage 20% (I doubt if I
would save that much), it would take 7.3 years to break even on the $700
up front cost.

So I would like to do it someday, but for now it is not at the top of my
priority list.


$700.00 seems a bit high for insulation. Wouldn't hurt to look around
a bit more. Check the people that blow in cellulose insulation.

Around here lumberyards will rent you an insulation blower when you
buy the bags of insulation from them. You can do it with the help of a
neighbor or two. Look around maybe you can find someone else that
wants to add insulation. You can help each other and split the cost of
the blower.

Don't let the bean counter math dissuade you. Energy costs will go up
but so will the cost of insulation. You will be in the same boat a few
years from now.

The math only looks at the money. It doesn't take into account that
your house will be more comfortable. That's not worth anything to a
bean counter but it's why people say to themselves " I wish I had done
that years ago."

If the insulation save money in energy costs it also save wear and
tear on your air conditioner. That will save you a few bucks as well.

LdB

On Sat, 26 May 2012 10:11:47 -0400, Home Guy wrote:

Tony Sivori wrote:

-snip-


Information overload grin !!!!

Tony Sivori wrote:
LdB wrote:
Improving attic insulation and ventilation will have a much bigger
effect on your heating and air conditioning costs. My new house is
over twice the size of my old house. The winter heating and summer
cooling costs are lower in the new house than in the old house.

The attic in the old house was like an oven in the summer.

That is what my miserable little scuttle is like, I'd guess it is 120
up there mid-day in the summer.


You're not even close. Think 140+.

my dad and family live in phoenix where the vast majority of shingles
are white for less attic heat and longer shingle life

On Fri, 25 May 2012 12:46:10 -0400, Tony Sivori
wrote:

I'm getting a new roof on my house. I'm considering changing to brown
shingles (Owens Corning Desert Tan) from white shingles.

If anyone here has any experience about increased air conditioning costs
after going to a darker roof, I would like know how much your bill went up
(or didn't).

Particulars would be most helpful, such as climate, and how well the attic
was insulated.

My own particulars: Louisville KY, ranch house, low pitched hip roof,
poorly insulated attic. Air conditioner ducts do not pass through attic.
House gets a fair amount of shade from trees located on East, South, and
West sides. But they are Maples, and I don't want to assume they will last
the next 30 years.

In my opinion, if you live where there are cold winters, a dark roof
will add heat in winter too, thus saving on heating costs, but that
will be offset in summer by higher AC bills. If the climate is in the
south without severe winters, I'd go for a light colored roof.

A compromise is a medium colored roof such as a gray or tan.
Personally I went with a tan on my roof, in a more north climate with
cold winters.

wrote:

In my opinion, if you live where there are cold winters, a dark
roof will add heat in winter too, thus saving on heating costs,

That is completely false.

That is so wrong, it's not even funny.

Your attic should be insulated such that there is NO ability to tranfer
heat IN ANY DIRECTION to or from the interior of your house. Think
about it. If any heat was being conducted from your attic into your
house IN THE WINTER, then can you imagine how much heat would be
conducted into your house IN THE SUMMER ?!

But the idea that your attic would even get warm enough in the winter to
have any useful heat is the biggest wrong assumption in your statement.
For one thing, the angle of the sun in the winter, the hours of
available sunlight, the likelyhood of more cloudy days in the winter -
and the fact that your roof could be covered with snow all combine to
give zero usefulness for having dark shingles in northern-latitude homes
as some form of energy (heat) capture.

but that will be offset in summer by higher AC bills.

It's still a flawed premis in the first place to propose that dark
shingles have heat-accumulating benefits for homes during the winter
months.

A compromise is a medium colored roof such as a gray or tan.
Personally I went with a tan on my roof, in a more north climate
with cold winters.

My climate is similar to Detroit, Buffalo, Cleveland or Toronto. I have
a tan roof. The upper floor has a pyramid-shaped roof (basically comes
to almost a point at the top). During the past week, the outside air
temperature has reached between 80 and 85 f, completely clear sky (no
clouds). The roof is not shaded by any trees at mid-day. Without the
roof fan running, the temperature in the attic will reach 135 f. With
the fan running, it will reach 115 f. Temperature is measured halfway
up one side of the roof, about 1" under the roof decking.

On Sat, 26 May 2012 17:00:27 -0700, Oren wrote:

On Sat, 26 May 2012 14:40:40 -0700 (PDT), bob haller
wrote:

my dad and family live in phoenix where the vast majority of shingles
are white for less attic heat and longer shingle life

Are these old homes? I've not yet seen a shingle roof in Phoenix. In
my travels through the town I see tile roofs. Some flat roofs may be
white? Back in the day, Las Vegas residents used white quartzes rock
on a roof to reflect the heat.


I believe when I was a youngster, my dad put a white shingled roof on
our house and as I recall, we were the only one or two in a large
subdivision with a white shingled roof. This was on Long Island, NY.
I don't recall them ever talking about the electric bill but I was
probably too young to care. My personal thought is that a white
shingle roof is probably minimally beneficial because since I've lived
in Texas and traveling around Houston and Austin, I don't recall
seeing any white shingled roofs. I would think with the heat we get
for many months a year, if it were really beneficial, they would have
a lot more of them around here. So my conclusion is that my father
(a builder then) and the homes I see now, do it for cosmetics more
than anything else.

On Sun, 27 May 2012 08:36:10 -0400, Home Guy wrote:

wrote:

In my opinion, if you live where there are cold winters, a dark
roof will add heat in winter too, thus saving on heating costs,

That is completely false.

That is so wrong, it's not even funny.

Your attic should be insulated such that there is NO ability to tranfer
heat IN ANY DIRECTION to or from the interior of your house. Think
about it. If any heat was being conducted from your attic into your
house IN THE WINTER, then can you imagine how much heat would be
conducted into your house IN THE SUMMER ?!

That is completely false.

That is so wrong, it's not even funny.

If there were "NO ability to transfer heat IN ANY DIRECTION to or from the
interior of your house", there would be no need for a furnace or AC, at all.
The fact is that heat transfer is finite and proportional to the delta-T.
Lower it and you *will* save money. The heat transfer is really delta-T/R, so
there are two knobs to turn. True, R is usually the easier knob to turn but
your statement, as made, is wrong.

But the idea that your attic would even get warm enough in the winter to
have any useful heat is the biggest wrong assumption in your statement.
For one thing, the angle of the sun in the winter, the hours of
available sunlight, the likelyhood of more cloudy days in the winter -
and the fact that your roof could be covered with snow all combine to
give zero usefulness for having dark shingles in northern-latitude homes
as some form of energy (heat) capture.

There is warming of the attic space in the Winter. Attics *should be*
designed to stay cold, but there is heating due to the sun. If there weren't,
ice dams would be unheard of.

but that will be offset in summer by higher AC bills.

It's still a flawed premis in the first place to propose that dark
shingles have heat-accumulating benefits for homes during the winter
months.

A compromise is a medium colored roof such as a gray or tan.
Personally I went with a tan on my roof, in a more north climate
with cold winters.

My climate is similar to Detroit, Buffalo, Cleveland or Toronto. I have
a tan roof. The upper floor has a pyramid-shaped roof (basically comes
to almost a point at the top). During the past week, the outside air
temperature has reached between 80 and 85 f, completely clear sky (no
clouds). The roof is not shaded by any trees at mid-day. Without the
roof fan running, the temperature in the attic will reach 135 f. With
the fan running, it will reach 115 f. Temperature is measured halfway
up one side of the roof, about 1" under the roof decking.

But physics is *so* much different in the Winter. giggle

" wrote:

Your attic should be insulated such that there is NO ability to
tranfer heat IN ANY DIRECTION to or from the interior of your
house.

If there were "NO ability to transfer heat IN ANY DIRECTION to or
from the interior of your house", there would be no need for a
furnace or AC, at all.

I didn't say that it was possible to have zero heat transfer.

So stop being disengenous.

You know dam well that a house can't "harvest" heat from the attic in
the winter.

You know dam well that your goal should be to have as little ability as
possible to transfer heat to or from the interior living space to the
attic. And given that goal, that the very idea of having dark shingles
for some kind of heat-benefit in the winter is crazy.

There is warming of the attic space in the Winter.

In the winter (as is the case in any season) - an attic space can (or
WILL) get warmer THAN OUTDOOR AMBIENT TEMPERATURE.

So what?

What good is it when it's 20 F outside and 30 F in my attic - when I
want it to be 72 F inside my house?

What am I going to do - install a heat pump in my attic to extract the
paltry amount of extra heat in the attic space?

It's still a flawed premis in the first place to propose that
dark shingles have heat-accumulating benefits for homes during
the winter months.

You did not comment on that statement.

Why?

Because it was true / accurate?

Tony Sivori wrote:
I'm getting a new roof on my house. I'm considering changing to brown
shingles (Owens Corning Desert Tan) from white shingles.


If you live in an urban environment, the white shingles will turn brown
given enough time. The particulate matter from auto exhausts - and other
pollutants - will stain them, but not evenly.

HeyBub wrote:

Tony Sivori wrote:
LdB wrote:
Improving attic insulation and ventilation will have a much bigger
effect on your heating and air conditioning costs. My new house is
over twice the size of my old house. The winter heating and summer
cooling costs are lower in the new house than in the old house.

The attic in the old house was like an oven in the summer.

That is what my miserable little scuttle is like, I'd guess it is 120
up there mid-day in the summer.


You're not even close. Think 140+.

Ok, I decided to check. I put a wired inside / outside thermometer up
there this morning.

It is now 3PM local, 90 and sunny outside, the roof is in 30% shade from
trees. The attic temperature is 121.

So I'd guess it could easily exceed 130 on the hottest days of summer, but
exceeding 140 might never happen in my particular attic.

--
Tony Sivori

Gomba wrote:
To me, Owens has always been more of a product any consumer can get
their hands on. _My_ choice was always Certainteed, then GAF.

I've been away from the products for a good 10 years. At that time,
Owens didn't have a hip & ridge cap. You basically would try to match a
conventional 3 tab color, to their architectural shingles. Don't know if
they ever decided to make a hip & ridge for their architectural's. Could
look it up, but am feeling a bit lazy.

OC does make a hip and ridge cap, it is in one the brochures that I got
with an estimate. In the photos, they don't look as thick as the ones from
GAF.

--
Tony Sivori

On Sun, 27 May 2012 13:14:42 -0400, Home Guy wrote:

" wrote:

Your attic should be insulated such that there is NO ability to
tranfer heat IN ANY DIRECTION to or from the interior of your
house.

If there were "NO ability to transfer heat IN ANY DIRECTION to or
from the interior of your house", there would be no need for a
furnace or AC, at all.

I didn't say that it was possible to have zero heat transfer.

Read what you wrote.

So stop being disengenous.

Write what you mean. Or learn something. Either way...

You know dam well that a house can't "harvest" heat from the attic in
the winter.

Wrong. Heat transfer is delta-T/R. Lower delta-T means a lower heating bill.
You know dam well that your goal should be to have as little ability as
possible to transfer heat to or from the interior living space to the
attic. And given that goal, that the very idea of having dark shingles
for some kind of heat-benefit in the winter is crazy.

"As little as possible" is *not* zero, as you said. For every 1F you can drop
delta-T, you save something like 2-3% of the heating bill (assuming an average
30-50F temperature rise).

There is warming of the attic space in the Winter.

In the winter (as is the case in any season) - an attic space can (or
WILL) get warmer THAN OUTDOOR AMBIENT TEMPERATURE.

So what?

It changes delta-T, that's what.

What good is it when it's 20 F outside and 30 F in my attic - when I
want it to be 72 F inside my house?

Because you only raising the temperature 42F rather than 52F, a 23% savings on
heat escaping through the ceiling (which you said was zero, above). Is 23% =
0?

What am I going to do - install a heat pump in my attic to extract the
paltry amount of extra heat in the attic space?

I know it's almost impossible, but you might try thinking.

It's still a flawed premis in the first place to propose that
dark shingles have heat-accumulating benefits for homes during
the winter months.

You did not comment on that statement.

Why?

Because you're a liar? Any heat in the attic *will* help. For completely
separate reasons, you want to minimize the heat in the attic, but it *does*
matter, here.

Because it was true / accurate?

No, because I already had.

On Sun, 27 May 2012 12:45:28 -0500, "HeyBub" wrote:

Tony Sivori wrote:
I'm getting a new roof on my house. I'm considering changing to brown
shingles (Owens Corning Desert Tan) from white shingles.


If you live in an urban environment, the white shingles will turn brown
given enough time. The particulate matter from auto exhausts - and other
pollutants - will stain them, but not evenly.

Not to mention that "bright red Georgia clay and how it stuck to the roof,
after the Summer rain". ;-)

zzzzzzzzzz wrote:
On Sun, 27 May 2012 12:45:28 -0500, "HeyBub"
wrote:

Tony Sivori wrote:
I'm getting a new roof on my house. I'm considering changing to
brown shingles (Owens Corning Desert Tan) from white shingles.


If you live in an urban environment, the white shingles will turn
brown given enough time. The particulate matter from auto exhausts -
and other pollutants - will stain them, but not evenly.

Not to mention that "bright red Georgia clay and how it stuck to the
roof, after the Summer rain". ;-)

In my part of the country, we call a mixture of red clay and water "adobe."

On Mon, 28 May 2012 08:57:49 -0500, "HeyBub" wrote:

wrote:
On Sun, 27 May 2012 12:45:28 -0500, "HeyBub"
wrote:

Tony Sivori wrote:
I'm getting a new roof on my house. I'm considering changing to
brown shingles (Owens Corning Desert Tan) from white shingles.


If you live in an urban environment, the white shingles will turn
brown given enough time. The particulate matter from auto exhausts -
and other pollutants - will stain them, but not evenly.

Not to mention that "bright red Georgia clay and how it stuck to the
roof, after the Summer rain". ;-)

In my part of the country, we call a mixture of red clay and water "adobe."

Nope, don't know that one. Maybe if you hum a coupla bars. ;-)

On 5/25/2012 11:46 AM, Tony Sivori wrote:
I'm getting a new roof on my house. I'm considering changing to brown
shingles (Owens Corning Desert Tan) from white shingles.

If anyone here has any experience about increased air conditioning costs
after going to a darker roof, I would like know how much your bill went up
(or didn't).

Particulars would be most helpful, such as climate, and how well the attic
was insulated.

My own particulars: Louisville KY, ranch house, low pitched hip roof,
poorly insulated attic. Air conditioner ducts do not pass through attic.
House gets a fair amount of shade from trees located on East, South, and
West sides. But they are Maples, and I don't want to assume they will last
the next 30 years.


IF (note the IF) the attic is insulated properly, the roof color will be
of no consequence. You will also be able to see the fungus on the north
side a lot more with the white than with the darker color. If your roof
does not have a north side, then disregard.

--
Steve Barker
remove the "not" from my address to email

Tony Sivori wrote:

That is what my miserable little scuttle is like, I'd guess it is
120 up there mid-day in the summer.


You're not even close. Think 140+.

Ok, I decided to check. I put a wired inside / outside thermometer up
there this morning.

It is now 3PM local, 90 and sunny outside, the roof is in 30% shade
from trees. The attic temperature is 121.

So I'd guess it could easily exceed 130 on the hottest days of
summer, but exceeding 140 might never happen in my particular attic.

I can believe that if you live in the Dakotas. My attic reached 150 before a
massive effort to reduce the temp was undertaken. The effort consisted of
four wind turbines, a ridge vent, and a SIGNIFICANT amount of fascia vents.

Now it seldom gets above 130.

Doug wrote:

I believe when I was a youngster, my dad put a white shingled roof on
our house and as I recall, we were the only one or two in a large
subdivision with a white shingled roof. This was on Long Island, NY.
I don't recall them ever talking about the electric bill but I was
probably too young to care. My personal thought is that a white
shingle roof is probably minimally beneficial because since I've lived
in Texas and traveling around Houston and Austin, I don't recall
seeing any white shingled roofs. I would think with the heat we get
for many months a year, if it were really beneficial, they would have
a lot more of them around here. So my conclusion is that my father
(a builder then) and the homes I see now, do it for cosmetics more
than anything else.

I think the reason you don't see light-colored roofs in a Texas urban
environment, or any urban environment for that matter, is they discolor from
the gunk and particulate matter in the air. The roofs, moreover, don't
discolor uniformly. They streak and in general look just horrid.

On Mon, 28 May 2012 18:38:01 -0500, "HeyBub"
wrote:

Doug wrote:

I believe when I was a youngster, my dad put a white shingled roof on
our house and as I recall, we were the only one or two in a large
subdivision with a white shingled roof. This was on Long Island, NY.
I don't recall them ever talking about the electric bill but I was
probably too young to care. My personal thought is that a white
shingle roof is probably minimally beneficial because since I've lived
in Texas and traveling around Houston and Austin, I don't recall
seeing any white shingled roofs. I would think with the heat we get
for many months a year, if it were really beneficial, they would have
a lot more of them around here. So my conclusion is that my father
(a builder then) and the homes I see now, do it for cosmetics more
than anything else.

I think the reason you don't see light-colored roofs in a Texas urban
environment, or any urban environment for that matter, is they discolor from
the gunk and particulate matter in the air. The roofs, moreover, don't
discolor uniformly. They streak and in general look just horrid.



Yea but the colors on the roof now show the same thing so I don't
think that's a white issue. I admit white might show a bit more
contrast when discoloring.