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Default doubling attic insulation - does it help?

I have a 5 year old house. I can't remember the R-value, but I know
I've got the yellow insulation batts in my attic. Its what is required
for code, no more I'm sure
The insulation has paper on 1 side (down), and nothing on the exposed
side (facing up) in the attic. I was wondering if I buy the white
insulation from H.Depot (higher R-value) and put it down ON TOP of the
yellow insulation. I don't think it will compress it much - the bats
are light. Perhaps that will provide me with $$ savings?

Thanks!
jason shohet

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Edwin Pawlowski
 
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Default doubling attic insulation - does it help?


wrote in message
ups.com...
I have a 5 year old house. I can't remember the R-value, but I know
I've got the yellow insulation batts in my attic. Its what is required
for code, no more I'm sure
The insulation has paper on 1 side (down), and nothing on the exposed
side (facing up) in the attic. I was wondering if I buy the white
insulation from H.Depot (higher R-value) and put it down ON TOP of the
yellow insulation. I don't think it will compress it much - the bats
are light. Perhaps that will provide me with $$ savings?

Thanks!
jason shohet


Anything helps, but keep in mind there are diminishing returns. Before you
jump into this, find out what you have and what is recommended for your
climate. In general, more is better. You can probably find some chart
showing what the potential savings are.
http://www.eere.energy.gov/consumer/.../mytopic=11360

Don't forget the basement
http://www.bchydro.com/powersmart/el...ibrary643.html
--
Ed
http://pages.cthome.net/edhome/


  #3   Report Post  
ESM
 
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Default doubling attic insulation - does it help?

I'm in FL, and blown in insulation is the big thing here. I had roughly
1800 sq ft blown in at an R19 value in fiberglass. Cost me $550 and I got a
$100 credit frm the power company, so $450 total. It took about 30 minutes
to be done, and the best part is that someone else was in the attic getting
sweaty. These guys will blown in at any R value, it just costs more.

You can buy cellulose as HD/Lowes, and if you buy enough, the machine rental
is free. I think I may have saved a few bucks if I did it myself, but even
if it was $100 I could have saved, to not sweat in the attic, it was worth
the cost.
Doing it with rolled out insulation would have been far more costly.

Downside to blown in stuff is it settles over time. My house is 25 years
old, had blown in fiberglass and it settles down to around an R10 value.
Probably was R19 originally. So now I'm at R30 range.

wrote in message
ups.com...
I have a 5 year old house. I can't remember the R-value, but I know
I've got the yellow insulation batts in my attic. Its what is required
for code, no more I'm sure
The insulation has paper on 1 side (down), and nothing on the exposed
side (facing up) in the attic. I was wondering if I buy the white
insulation from H.Depot (higher R-value) and put it down ON TOP of the
yellow insulation. I don't think it will compress it much - the bats
are light. Perhaps that will provide me with $$ savings?

Thanks!
jason shohet



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Bill
 
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Default doubling attic insulation - does it help?

Great energy saving tips are at the following link. I would do everything
you possibly can. For example I just got a new "Energy Star" refrigerator
and it is saving me $10 a month on my electric bill. Strange that a new
appliance could do the same thing while using less energy, but I guess they
figured out some way to make these thing more efficient. These suggestions
*really* help to lower energy bills.

Some things are expensive like replacing windows, others are cheap like
sealing leaks - caulking, etc.

Energy saving tips...
http://www.energystar.gov/


  #5   Report Post  
Doug Kanter
 
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Default doubling attic insulation - does it help?


wrote in message
ups.com...
I have a 5 year old house. I can't remember the R-value, but I know
I've got the yellow insulation batts in my attic. Its what is required
for code, no more I'm sure
The insulation has paper on 1 side (down), and nothing on the exposed
side (facing up) in the attic. I was wondering if I buy the white
insulation from H.Depot (higher R-value) and put it down ON TOP of the
yellow insulation. I don't think it will compress it much - the bats
are light. Perhaps that will provide me with $$ savings?

Thanks!
jason shohet


Just be sure not to block your attic ventilation, especially if you're in a
climate where you get snow & ice that hang around for long periods of time.




  #6   Report Post  
m Ransley
 
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Default doubling attic insulation - does it help?

Measure what you have and if fiberglass figure 3.5 per inch R value.
All insulation settles.

Codes are minimums. Previous sites provided will give you optimal R
values for your Zone.,

Also check out Owens Corning, Dow, and other R value energy sites.

Im Zone 5 , Code is R 35, optimal is stated at several sites R 60 -
70. I did R 100 and it has settled to R 80. My utilities are the lowest
in the area confirmed by the utility co, but I did the walls , windows
and basement also.

Up what you have past optimal ratings for settling and you will save
big time. Remember Heat Rises, the attic is the cheapest place to start
Be sure to instal side roof deck baffles.

Codes are basicly 30 + years old, minimums, and do not reflect todays
utilities prices .

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TURTLE
 
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Default doubling attic insulation - does it help?


wrote in message
ups.com...
I have a 5 year old house. I can't remember the R-value, but I know
I've got the yellow insulation batts in my attic. Its what is required
for code, no more I'm sure
The insulation has paper on 1 side (down), and nothing on the exposed
side (facing up) in the attic. I was wondering if I buy the white
insulation from H.Depot (higher R-value) and put it down ON TOP of the
yellow insulation. I don't think it will compress it much - the bats
are light. Perhaps that will provide me with $$ savings?

Thanks!
jason shohet


This is Turtle.

Ed and other had some good replys but there is one thing to remember here. There
is such a thing as over insulating the attic. a example of this is put 10 feet
of insulation in your attic and then when the evening comes when the temperature
cools off . your attic has this 10 feet of insulation which will still be
transnitting heat into your house most of the nite. then when the morning comes
you will have to start heating up the 10 feet of insulation from inside the home
which will waste a lot of heat to just do this. So Too much is just as bad as
not enough.

TURTLE


  #8   Report Post  
Duane Bozarth
 
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Default doubling attic insulation - does it help?

Wes Stewart wrote:

....

Insulation has that much thermal mass?


No.
  #9   Report Post  
Wes Stewart
 
Posts: n/a
Default doubling attic insulation - does it help?

On Mon, 17 Oct 2005 11:18:12 -0500, "TURTLE"
wrote:


wrote in message
oups.com...
I have a 5 year old house. I can't remember the R-value, but I know
I've got the yellow insulation batts in my attic. Its what is required
for code, no more I'm sure
The insulation has paper on 1 side (down), and nothing on the exposed
side (facing up) in the attic. I was wondering if I buy the white
insulation from H.Depot (higher R-value) and put it down ON TOP of the
yellow insulation. I don't think it will compress it much - the bats
are light. Perhaps that will provide me with $$ savings?

Thanks!
jason shohet


This is Turtle.

Ed and other had some good replys but there is one thing to remember here. There
is such a thing as over insulating the attic. a example of this is put 10 feet
of insulation in your attic and then when the evening comes when the temperature
cools off . your attic has this 10 feet of insulation which will still be
transnitting heat into your house most of the nite. then when the morning comes
you will have to start heating up the 10 feet of insulation from inside the home
which will waste a lot of heat to just do this. So Too much is just as bad as
not enough.


Insulation has that much thermal mass?
  #10   Report Post  
Duane Bozarth
 
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Default doubling attic insulation - does it help?

TURTLE wrote:

....
...So Too much is just as bad as not enough.


Not from the above cause. Too much (or more likely, poorly installed)
could be a problem if you were to block necessary air circulation, but
any realistic amount would not be a problem as described by thermal mass
and re-radiation back into the living space.


  #11   Report Post  
m Ransley
 
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Default doubling attic insulation - does it help?

Turtle, insulation needs vary upon locality-zone. You pay to heat or
cool and more attic insulation helps. Many areas have heating as the
major cost not cooling, but I always find nightime humidities to high
during cooling season to open windows, although I agree in theory wth
you as I noticed what you mention, but the winter and overall savings up
north here negate what you experiance in your warmer locality. Uping R
even cut my summer cooling bills as heat is not let in the attic. Ten
feet of it you say, that would be upwards of R 420, kind of stupid for
you to say Ten Feet. Facts and proof are out there that codes are
insuficient minimums, there are guidlines that work to get optimal
values. You don`t live where your new heating bills may be up hundreds a
month or where a 90% furnace is not as good as a 94.5%. and a 80%
efficiency is a joke.

  #12   Report Post  
 
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Default doubling attic insulation - does it help?

TURTLE wrote:

...There is such a thing as over insulating the attic. a example of this is
put 10 feet of insulation in your attic and then when the evening comes when
the temperature cools off . your attic has this 10 feet of insulation which
will still be transnitting heat into your house most of the nite...


No.

Nick

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Wes Stewart
 
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Default doubling attic insulation - does it help?

On 16 Oct 2005 19:13:29 -0700, wrote:

I have a 5 year old house. I can't remember the R-value, but I know
I've got the yellow insulation batts in my attic. Its what is required
for code, no more I'm sure
The insulation has paper on 1 side (down), and nothing on the exposed
side (facing up) in the attic. I was wondering if I buy the white
insulation from H.Depot (higher R-value) and put it down ON TOP of the
yellow insulation. I don't think it will compress it much - the bats
are light. Perhaps that will provide me with $$ savings?



Here's a (really) simple little thought experiment. Pretend you are
in a cooling situation so that you are trying to minimize the internal
heat gain.

Let's start with walls and roof with no added insulation and say that
the construction materials give an R value = 1. The heat gain comes
from the following sources:

1. Internal (appliances, hot bodies, etc.) 30%

2. Roof 40%

3. South wall (lots of overhang) 5%

4. North wall 5%

5. East wall 10%

6. West wall 10%

Assume the total daily heat gain for a typical day is 100,000 BTU, so
the distribution is as follows:

Internal = 30,000 BTU

Roof = 40,000 BTU

South wall = 5,000 BTU

North wall = 5,000 BTU

East wall = 10,000 BTU

West wall = 10,000 BTU.

Now, let's stuff some R-10 (U = 0.1) insulation under the roof. This
reduces the transfer to 10% of the starting point or 4,000 BTU.

The total heat gain drops to 64,000 BTU, or a 36% reduction. Hey,
this is progress, let's double the amount and really save some dough.

Adding another R-10 layer for R-20 total reduces the roof heat gain to
2000 BTU, for a total of 62,000 BTU, or a 38% reduction from the
starting point.

Wait a minute! We doubled the insulation (and its cost) and saved 2%.
Clearly, the other sources should be addressed before going overboard
with ceiling insulation. You can argue about the beginning
distributions, but the trend is clear. Unfortunately, building codes
sometimes take the position that if some's good, more's better, which
is complete nonsense.

I also find it amusing that some builders, as I've seen here in
Tucson, offer hype such has "R-40 ceilings, and R-30 walls" when 80%
of an unshaded west facing wall is sliding glass doors. The 20% shear
wall is R-30 alright, but the 80% is R-1.5 and might as well be a hole
in the wall through which you pour money.
  #14   Report Post  
PipeDown
 
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Default doubling attic insulation - does it help?


"Wes Stewart" wrote in message
...
On 16 Oct 2005 19:13:29 -0700, wrote:

I have a 5 year old house. I can't remember the R-value, but I know
I've got the yellow insulation batts in my attic. Its what is required
for code, no more I'm sure
The insulation has paper on 1 side (down), and nothing on the exposed
side (facing up) in the attic. I was wondering if I buy the white
insulation from H.Depot (higher R-value) and put it down ON TOP of the
yellow insulation. I don't think it will compress it much - the bats
are light. Perhaps that will provide me with $$ savings?



Here's a (really) simple little thought experiment. Pretend you are
in a cooling situation so that you are trying to minimize the internal
heat gain.

Let's start with walls and roof with no added insulation and say that
the construction materials give an R value = 1. The heat gain comes
from the following sources:

1. Internal (appliances, hot bodies, etc.) 30%

2. Roof 40%

3. South wall (lots of overhang) 5%

4. North wall 5%

5. East wall 10%

6. West wall 10%

Assume the total daily heat gain for a typical day is 100,000 BTU, so
the distribution is as follows:

Internal = 30,000 BTU

Roof = 40,000 BTU

South wall = 5,000 BTU

North wall = 5,000 BTU

East wall = 10,000 BTU

West wall = 10,000 BTU.

Now, let's stuff some R-10 (U = 0.1) insulation under the roof. This
reduces the transfer to 10% of the starting point or 4,000 BTU.

The total heat gain drops to 64,000 BTU, or a 36% reduction. Hey,
this is progress, let's double the amount and really save some dough.

Adding another R-10 layer for R-20 total reduces the roof heat gain to
2000 BTU, for a total of 62,000 BTU, or a 38% reduction from the
starting point.

Wait a minute! We doubled the insulation (and its cost) and saved 2%.
Clearly, the other sources should be addressed before going overboard
with ceiling insulation. You can argue about the beginning
distributions, but the trend is clear. Unfortunately, building codes
sometimes take the position that if some's good, more's better, which
is complete nonsense.

I also find it amusing that some builders, as I've seen here in
Tucson, offer hype such has "R-40 ceilings, and R-30 walls" when 80%
of an unshaded west facing wall is sliding glass doors. The 20% shear
wall is R-30 alright, but the 80% is R-1.5 and might as well be a hole
in the wall through which you pour money.



Consider the gross simplification where all 4 walls and ceiling had the same
area and R factor (ignoring the floor). Doubling the amount of insulation
would decrease the heat lost by 50% over 20% of the area or a total of 10%
overall.

Since ceilings are generally better insulated than walls (which have doors
and windows) and (especially in a 2 storey house) have less area than the
total wall area, the actual improvement from doubling the ceiling insulation
I would expect to be much less than 10%.



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m Ransley
 
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Default doubling attic insulation - does it help?

So how did I get an 1800sq. ft. 110 yr old house to have an annual gas
bill of 463$ last year, down from 1850 $, Which includes tankless gas
water heater gas cooking and gas dryer. I did R 100 attic R 35 walls,
dual and tri pane, and complete basement insulation, even Under the new
concrete. But #1 I did not listen to the naysayers that I would never
get a payback. My utility co was so sure I was stealing they were out
twice. So all you who say don`t overdo it , it will never payback, I
laugh to the bank this year and maybe pay 6-700 for a years worth of
comfort.

Oh Im Zone 5 Chicago area it goes to -20 here and im on the water, a
very windy place indeed, so windows were purchased with test results.

Bottom line, insulate for your zone to the max.



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m Ransley
 
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Default doubling attic insulation - does it help?

No I cant relate savings to a single thing I did, it was all done at
once, but the utility co Nipsco said I have the lowest bills they know
of for my size house. Point being there is alot most can do in different
areas of waste, people should not be closed to the fact, or discoured.
Utility savings can be found im many areas of improvement. With Ng being
up 50-70% and electric soon in my area 15-40% there is alot anyone can
do, anywhere. My yearly electric with AC is also extremly low apx 260 -
290 a year. Its all a matter of researching before you buy and what can
realy save an extra$. Did you know sears makes the most efficient 19.5
frige, it is equal to Sun Frost in efficiency, in standard form and
resessed with extra insulation more than Sun Frost. Do you own heat end
electric audit, and keep an open mind.

  #19   Report Post  
PaPaPeng
 
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Default doubling attic insulation - does it help?

On Mon, 17 Oct 2005 03:16:04 GMT, "ESM" wrote:

Downside to blown in stuff is it settles over time. My house is 25 years
old, had blown in fiberglass and it settles down to around an R10 value.
Probably was R19 originally. So now I'm at R30 range.


Attended a house building course years ago when I was building mine
with sweat equity. On insulation calculations the data was that up
to R30 the gain in insulation efficiency is a straight slope upwards.
After R30 the slope flattens which is to say any gain in insulation
efficiency ( reduction in heat loss) after R30 is very marginal. That
is you won't get your money's worth beyond R30.

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TURTLE
 
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Default doubling attic insulation - does it help?


"Wes Stewart" wrote in message
...
On Mon, 17 Oct 2005 11:18:12 -0500, "TURTLE"
wrote:


wrote in message
roups.com...
I have a 5 year old house. I can't remember the R-value, but I know
I've got the yellow insulation batts in my attic. Its what is required
for code, no more I'm sure
The insulation has paper on 1 side (down), and nothing on the exposed
side (facing up) in the attic. I was wondering if I buy the white
insulation from H.Depot (higher R-value) and put it down ON TOP of the
yellow insulation. I don't think it will compress it much - the bats
are light. Perhaps that will provide me with $$ savings?

Thanks!
jason shohet


This is Turtle.

Ed and other had some good replys but there is one thing to remember here.
There
is such a thing as over insulating the attic. a example of this is put 10 feet
of insulation in your attic and then when the evening comes when the
temperature
cools off . your attic has this 10 feet of insulation which will still be
transnitting heat into your house most of the nite. then when the morning
comes
you will have to start heating up the 10 feet of insulation from inside the
home
which will waste a lot of heat to just do this. So Too much is just as bad as
not enough.


Insulation has that much thermal mass?


This is Turtle

No the Air in the Insulation does have a good mass to concider but the
insulation it's self would only very small in the effect. A example of this is
the perfect insulation is a 1" block of a glass cube with a vacuum space in side
it. Heat will not transfer in a vacuum except it is a radian heat. The vacuum
cube would be the perfect insulation and put all the insulation companys out of
business.

TURTLE




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PipeDown
 
Posts: n/a
Default doubling attic insulation - does it help?


"m Ransley" wrote in message
...
No I cant relate savings to a single thing I did, it was all done at
once, but the utility co Nipsco said I have the lowest bills they know
of for my size house. Point being there is alot most can do in different
areas of waste, people should not be closed to the fact, or discoured.
Utility savings can be found im many areas of improvement. With Ng being
up 50-70% and electric soon in my area 15-40% there is alot anyone can
do, anywhere. My yearly electric with AC is also extremly low apx 260 -
290 a year. Its all a matter of researching before you buy and what can
realy save an extra$. Did you know sears makes the most efficient 19.5
frige, it is equal to Sun Frost in efficiency, in standard form and
resessed with extra insulation more than Sun Frost. Do you own heat end
electric audit, and keep an open mind.


No doubt ~$1400/yr savings is very impressive. But how much did all new
appliances, new water heater, new windows, lots of insulation and whatever
else cost you. How many years will it take to pay back. Sounds like you
did a lot of remodeling at the same time and energy upgrades were just
addons (above and beyond the cost for basic installations). I assume you
didn't do all the work just to save fuel, there must be some cosmetic
payoff. The best time to upgrade is during a remodel.






  #22   Report Post  
TURTLE
 
Posts: n/a
Default doubling attic insulation - does it help?


"m Ransley" wrote in message
...
Turtle, insulation needs vary upon locality-zone. You pay to heat or
cool and more attic insulation helps. Many areas have heating as the
major cost not cooling, but I always find nightime humidities to high
during cooling season to open windows, although I agree in theory wth
you as I noticed what you mention, but the winter and overall savings up
north here negate what you experiance in your warmer locality. Uping R
even cut my summer cooling bills as heat is not let in the attic. Ten
feet of it you say, that would be upwards of R 420, kind of stupid for
you to say Ten Feet. Facts and proof are out there that codes are
insuficient minimums, there are guidlines that work to get optimal
values. You don`t live where your new heating bills may be up hundreds a
month or where a 90% furnace is not as good as a 94.5%. and a 80%
efficiency is a joke.


This is Turtle.

10 feet of insulation was a example of there is a limit to having too much and
just as not having enought.

TURTLE


  #23   Report Post  
 
Posts: n/a
Default doubling attic insulation - does it help?

One thing I note is that projected savings are figured at todays
fuel/energy cost. I have not kept track but I suspect that my actual
fuel savings from buying a 5 speed manual Honda civic 5 years ago
rather than a suk is a bit more than was projected. And if you think
energy prices are going down (except in world wide depression) I have
a great mony making deal for you.
Stan
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