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Dan White Posted: Mar 25, 2009 01:08 PM	Need Help with Insulation Decision Hi. I am trying to make some decisions on spray insulation but it is so easy to get lost in all of the information online. I’d like to post my situation and see if anyone can give me some advice: We are in the middle of a home renovation in northern New Jersey. We added a second level on top of a split and pushed out the back of the house, went with an open floor plan on the main floor. Total sf is somewhere around 2800 sf. Plus unfinished basement. We were not considering foam insulation until just recently (didn’t know anything about it, contractor didn’t either). Anyway now we’re in a bit of a rush situation where we are ready to put up fiberglass batts and are rethinking what to do. Tyvek has already been wrapped around the house, but siding isn’t up yet. I had two foam spray companies come out for an estimate. Due to our budget (which wasn’t planning on foam) the first company recommended that we spray the walls in the main floor, the 3 bedroom split level, and the new master level above the main floor. They said to put 8” batts down in the attic instead of spraying and that we’d be in good shape. Also, the estimate does not include the basement, garage, or the den, which is connected to the garage on the level between the basement and the main level. The den would either be done in the future, or we will just do batts when that room gets renovated later this year. Our exterior walls are 4”. So the first company recommends closed cell and charges about $11,500. He seemed to have a lot of experience and was thorough about showing me what he was going to do. The second company, more of a big box kind of operation, strongly recommended that we go with open cell because he said the house still needed to breathe. Their quote was $7400 for 4” open cell or $8500 for 2” closed cell if we insisted on closed cell. They said the insulation R value would be the same either way. So now I’m confused. I know it is hard to say, but I’m wondering if I really am going to see a return on my money with this plan. I have a new HVAC in the basement and a smaller one in the attic for just the new master bedroom floor (about 900 sf). Also, the open cell seems so much more fragile. I thought we were trying to stop the house from breathing, and that is where a lot of the energy savings comes from. One last thing. The closed cell company said that if I get an energy audit done on the house after spraying, I could get a check from the govt up to $5000, less for sure in my case. I am waiting to talk to the audit guy (a separate company) to find out more. I guess that’s about it. Can anyone give me some ideas to consider?
mason Posted: Mar 25, 2009 02:10 PM	You could use some education on sprayfoam and building science principles. Go to my website (masonknowles.com) and download the following articles. Learning the difference between 1/2 lb and 2 lb density SPF. Understanding R Values and REmodeling Solutions with SPF. This will give you the non-marketing information on the open and closed cell foam and information on R values and energy performance of SPF. Both open cell can closed cell can be used in your area, the open cell will require a vapor retarder element over the foam. As for breathing, you are correct, the idea is to reduce air infiltration so that you can control the air going into and out of the home. Next, as for R value, 1/2 foam (open cell) has around 3.5 to 3.6 R value per inch while the 2 lb foam (closed cell) averages around 6 per inch. (some formulas may go higher). Both can be used to effectively insulate your walls and ceiling. I am not a fan of blown in fiberglass in attics. Oakridge National Labs (Department of Energy) has determined in their attic climate simulator that blown in fiberglass due to convective currents loses almost half of its insulation efficiency while the sprayfoam maintains 70 to 80% of its efficiency. This does not take into consideration any energy loss due to air infiltration, which again the sprayfoam would greatly reduce.
Gerry Wagoner Posted: Mar 25, 2009 08:48 PM	Dear Bush: There are four compelling reasons to use closed-cell foam in a studwall assembly. They are: * Greater Insulation value * Tremendous Strength * Built in vapor barrier. * No need to fill the stud cavity. As to the fiberglass, the only place I recommend it is as an air filter. It is thoroughly unsatisfactory as an insulation material. There is a full chorus of voices asserting this, including a dozen customers per month who call here and complain about the poor performance of fiberglass. I wish I had better news for them, but the ones with fiberglass in their studwalls are stuck (unless they are willing to remove the drywall). I do wish you well, og (in our 25th year)
Angus McDougald Posted: Mar 26, 2009 07:57 AM	I can and will help you call me at 732-221-9574 My gf is a BPI certified energy auditor, and we regularly work with the comfort partners program and get our customers 2-6 thousand back fron nj state. We spray foam and blow cellulose, and we install solar. it is a tiered program where you get up to 50% back on up to a 10000 job. In addition there is also a free 1000 attic air-sealing. www.njcep.com is the nj govt site that oversees many of the rebates. look for- home performance with energy star You need the audit beforehand, or they are basically committing fraud. In my opinion fiberglass in all cases sucks. If you want to cheap out and get a good product I use cellulose AFTER air sealing. I also spray both OC and CC so many times we spray both, and maybe blow cellulose. I am not in the "building needs to breathe" camp I prefer to have a house super tight then control ventilation intentionally if needed. In retrofits, we generally do not need mechanical ventilation, but there is a blower door testout that will ensure the quality of the work and the safety of your home.
Dennis Davidson Posted: Mar 26, 2009 08:16 AM	In addition to the great attributes listed above for closed cell foam, you can include: Eliminates mold growth within the insulation Adds 70-200% Structural strength (stated above) Reduces or eliminates entry for rodents & insects. Reduces outside noise Increases home re-sale value As far as open cell foam goes - It makes great pillows & cushions for the furniture.
Dennis Davidson Posted: Mar 27, 2009 04:06 PM	My comment about open cell foam may have been a little harsh. Open cell does have it's place in the market. It's up to the contractor and the customer to make an educated decision about any product they intend to use.
Dan White Posted: Mar 27, 2009 07:13 PM	Thanks for the responses. I think I've gotten some really good advice here and by phone.
Posted: Mar 29, 2009 04:45 PM	....3600sq ft 3" cc thruout,,yes basement foundation too,,, 4-6" oc on drywall lid from attic to seal,,, $498 per year in LP for heat in addition to the Geothermal heat pump thingy,,, the first winter they did not "top out" the attic over our OC seal,,,the owner did not appreciate much difference in savings when he added and additional r40 of cellulose over the top of the foam,,,, ,,,foamed me just like jelly roll,,and she foamed me,,,
Posted: Mar 29, 2009 04:50 PM	,,,3800 sq ft with walkout,,,geothermal too,,, 1" building envelope via CC with BIBBS followed with 3-4" OC seal to the attic lid with R40 filterglass as a topper for design spec,,, owner reports $90 being top winter heat bill here in the cornfields of eastern iowa,,, anecdotal,,i know,, just tryin to help with the decision,,, ,,,and the wind screamed,,,foam me,,,
Posted: Mar 29, 2009 04:54 PM	...replaced R38 filterglass insulation in an attic with 10" OC in its place,,, colder winter than previous year,,,2 more days in billing period,,, daily natural gas ( for heat and hot water in this home ) reduced from $5.98/day to 3.01/day which is a reduction of 49%,,,which meant $70 to the customers pocket,,, ...should i foam or should i blow now???if i foam it will be double,,,if i blow it will be trouble,,so common and let me know,,,,,, should i foam or should i blow????????

Author

Comments

Dan White

Posted: Mar 25, 2009 01:08 PM

Need Help with Insulation Decision

Hi. I am trying to make some decisions on spray insulation but it is so easy to get lost in all of the information online. I’d like to post my situation and see if anyone can give me some advice:
We are in the middle of a home renovation in northern New Jersey. We added a second level on top of a split and pushed out the back of the house, went with an open floor plan on the main floor. Total sf is somewhere around 2800 sf. Plus unfinished basement. We were not considering foam insulation until just recently (didn’t know anything about it, contractor didn’t either). Anyway now we’re in a bit of a rush situation where we are ready to put up fiberglass batts and are rethinking what to do. Tyvek has already been wrapped around the house, but siding isn’t up yet.
I had two foam spray companies come out for an estimate. Due to our budget (which wasn’t planning on foam) the first company recommended that we spray the walls in the main floor, the 3 bedroom split level, and the new master level above the main floor. They said to put 8” batts down in the attic instead of spraying and that we’d be in good shape. Also, the estimate does not include the basement, garage, or the den, which is connected to the garage on the level between the basement and the main level. The den would either be done in the future, or we will just do batts when that room gets renovated later this year. Our exterior walls are 4”.
So the first company recommends closed cell and charges about $11,500. He seemed to have a lot of experience and was thorough about showing me what he was going to do. The second company, more of a big box kind of operation, strongly recommended that we go with open cell because he said the house still needed to breathe. Their quote was $7400 for 4” open cell or $8500 for 2” closed cell if we insisted on closed cell. They said the insulation R value would be the same either way.
So now I’m confused. I know it is hard to say, but I’m wondering if I really am going to see a return on my money with this plan. I have a new HVAC in the basement and a smaller one in the attic for just the new master bedroom floor (about 900 sf).
Also, the open cell seems so much more fragile. I thought we were trying to stop the house from breathing, and that is where a lot of the energy savings comes from.
One last thing. The closed cell company said that if I get an energy audit done on the house after spraying, I could get a check from the govt up to $5000, less for sure in my case. I am waiting to talk to the audit guy (a separate company) to find out more.
I guess that’s about it. Can anyone give me some ideas to consider?

mason

Posted: Mar 25, 2009 02:10 PM

You could use some education on sprayfoam and building science principles. Go to my website (masonknowles.com) and download the following articles. Learning the difference between 1/2 lb and 2 lb density SPF. Understanding R Values and REmodeling Solutions with SPF.

This will give you the non-marketing information on the open and closed cell foam and information on R values and energy performance of SPF.

Both open cell can closed cell can be used in your area, the open cell will require a vapor retarder element over the foam. As for breathing, you are correct, the idea is to reduce air infiltration so that you can control the air going into and out of the home.

Next, as for R value, 1/2 foam (open cell) has around 3.5 to 3.6 R value per inch while the 2 lb foam (closed cell) averages around 6 per inch. (some formulas may go higher). Both can be used to effectively insulate your walls and ceiling.

I am not a fan of blown in fiberglass in attics. Oakridge National Labs (Department of Energy) has determined in their attic climate simulator that blown in fiberglass due to convective currents loses almost half of its insulation efficiency while the sprayfoam maintains 70 to 80% of its efficiency. This does not take into consideration any energy loss due to air infiltration, which again the sprayfoam would greatly reduce.

Gerry Wagoner

Posted: Mar 25, 2009 08:48 PM

Dear Bush:

There are four compelling reasons to use closed-cell foam in a studwall assembly. They are:

* Greater Insulation value
* Tremendous Strength
* Built in vapor barrier.
* No need to fill the stud cavity.

As to the fiberglass, the only place I recommend it is as an air filter. It is thoroughly unsatisfactory as an insulation material. There is a full chorus of voices asserting this, including a dozen customers per month who call here and complain about the poor performance of fiberglass. I wish I had better news for them, but the ones with fiberglass in their studwalls are stuck (unless they are willing to remove the drywall).

I do wish you well,

og

(in our 25th year)

Angus McDougald

Posted: Mar 26, 2009 07:57 AM

I can and will help you
call me at 732-221-9574

My gf is a BPI certified energy auditor, and we regularly work with the comfort partners program and get our customers 2-6 thousand back fron nj state. We spray foam and blow cellulose, and we install solar.

it is a tiered program where you get up to 50% back on up to a 10000 job. In addition there is also a free 1000 attic air-sealing. www.njcep.com
is the nj govt site that oversees many of the rebates. look for- home performance with energy star

You need the audit beforehand, or they are basically committing fraud.

In my opinion fiberglass in all cases sucks. If you want to cheap out and get a good product I use cellulose AFTER air sealing. I also spray both OC and CC so many times we spray both, and maybe blow cellulose.

I am not in the "building needs to breathe" camp I prefer to have a house super tight then control ventilation intentionally if needed. In retrofits, we generally do not need mechanical ventilation, but there is a blower door testout that will ensure the quality of the work and the safety of your home.

Dennis Davidson

Posted: Mar 26, 2009 08:16 AM

In addition to the great attributes listed above for closed cell foam, you can include:
Eliminates mold growth within the insulation
Adds 70-200% Structural strength (stated above)
Reduces or eliminates entry for rodents & insects.
Reduces outside noise
Increases home re-sale value
As far as open cell foam goes - It makes great pillows & cushions for the furniture.

Dennis Davidson

Posted: Mar 27, 2009 04:06 PM

My comment about open cell foam may have been a little harsh. Open cell does have it's place in the market. It's up to the contractor and the customer to make an educated decision about any product they intend to use.

Dan White

Posted: Mar 27, 2009 07:13 PM

Thanks for the responses. I think I've gotten some really good advice here and by phone.

Posted: Mar 29, 2009 04:45 PM

....3600sq ft
3" cc thruout,,yes basement foundation too,,,
4-6" oc on drywall lid from attic to seal,,,

$498 per year in LP for heat in addition to the Geothermal heat pump thingy,,,

the first winter they did not "top out" the attic over our OC seal,,,the owner did not appreciate much difference in savings when he added and additional r40 of cellulose over the top of the foam,,,,

,,,foamed me just like jelly roll,,and she foamed me,,,

Posted: Mar 29, 2009 04:50 PM

,,,3800 sq ft with walkout,,,geothermal too,,,
1" building envelope via CC with BIBBS followed with 3-4" OC seal to the attic lid with R40 filterglass as a topper for design spec,,,
owner reports $90 being top winter heat bill here in the cornfields of eastern iowa,,,
anecdotal,,i know,,
just tryin to help with the decision,,,

,,,and the wind screamed,,,foam me,,,

Posted: Mar 29, 2009 04:54 PM

...replaced R38 filterglass insulation in an attic with 10" OC in its place,,,
colder winter than previous year,,,2 more days in billing period,,,
daily natural gas ( for heat and hot water in this home ) reduced from $5.98/day to 3.01/day which is a reduction of 49%,,,which meant $70 to the customers pocket,,,

...should i foam or should i blow now???if i foam it will be double,,,if i blow it will be trouble,,so common and let me know,,,,,,
should i foam or should i blow????????

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