Spray Foam vs Fiberglass insulation??

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Jason_Fairfax
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Spray Foam vs Fiberglass insulation??

#1 Post by Jason_Fairfax »

Is their a big difference in which method is used? my installer utilizes fiberglass insulation and I'm wondering if I'm making a big mistake by not opting for an installer that uses Spray foam...

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Windows on Washington
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Re: Spray Foam vs Fiberglass insulation??

#2 Post by Windows on Washington »

Technically speaking..yes.

One stops air, one does not.

Speaking from an installation standpoint, fiberglass is permissible as long as the envelope of the building shell and the connection between the insert and the home is properly sealed back up.

Spray foam is also a better insulator with a higher R-Value per inch.

akaluther
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Re: Spray Foam vs Fiberglass insulation??

#3 Post by akaluther »

If you have ever seen what that pink insulation looks like when you replace an old window, you will know your answer right away. Most often the pink will have turned black as it only acts as filter and captures all of the dirt and environmental contaminants that air have carried in. If there is also a history of water infiltration, the fiberglass will hold the water and be the perfect breeding ground for mold.
Foam is definitely the way to go. But be aware not all foams are the same. Be sure to choose a low pressure, minimally expanding, CLOSED CELL version. The closed cell will prevent water absorption. I would recommend OSI Winteq.

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Windows on Washington
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Re: Spray Foam vs Fiberglass insulation??

#4 Post by Windows on Washington »

All low pressure foams are closed cell and the formulations are very similar.

OSI Teq Foam is good as is Hilti, Great Stuff, etc.

That is why we call fiberglass...filterglass.

tru_blue
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Re: Spray Foam vs Fiberglass insulation??

#5 Post by tru_blue »

Windows on Washington wrote:That is why we call fiberglass...filterglass.
+1 What he said.

I've noticed over the years more and more window manufacturers changing their installation instructions to suggest or require the use of foam instead of fiberglass.

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Randy
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Re: Spray Foam vs Fiberglass insulation??

#6 Post by Randy »

The only way fiberglass works at all, around windows, is if the cavity is completely air-sealed on all sides. While that is possible, it's often difficult to accomplish and maintain. On the other hand, spray foam insulation is itself an air barrier, as well as an insulator.

Bottom, line; hands down, spray foam is the way to go.

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HomeSealed
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Re: Spray Foam vs Fiberglass insulation??

#7 Post by HomeSealed »

+1 to all. Spray foam is the way to go.... closed cell, low-expansion.

tuttle3000
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Re: Spray Foam vs Fiberglass insulation??

#8 Post by tuttle3000 »

It seems that most of you recommend the foam insulation. However, so far I have found only one contractor in the Pittsburgh area offering this for Gorell, Soft-lite, and Sunrise. I have only spoken with three contractors and I am wondering if my area is an anomaly or have I simply spoken with three unique people.

It seems to me that foam would do a better job in general.

Skydawggy.
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Re: Spray Foam vs Fiberglass insulation??

#9 Post by Skydawggy. »

Hopefilly the "Foamers" are not causing you to overlook some very good installers. Whether an installer does or doesn't use foam should not be a major consideration.

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Randy
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Re: Spray Foam vs Fiberglass insulation??

#10 Post by Randy »

It seems to me that foam would do a better job in general.
You're right, it's really common sense. Even if "non-foamers" disagree. :D

tuttle3000
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Re: Spray Foam vs Fiberglass insulation??

#11 Post by tuttle3000 »

EcoStar Windows wrote:Hopefilly the "Foamers" are not causing you to overlook some very good installers. Whether an installer does or doesn't use foam should not be a major consideration.

The foam vs fiberglass insulation is not a deal breaker in my opinion. If all things are equal, I would prefer foam since it seems to be a better insulator. I have no intention of overlooking a good installer. I am simply trying to find one. :)

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HomeSealed
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Re: Spray Foam vs Fiberglass insulation??

#12 Post by HomeSealed »

tuttle3000 wrote:It seems that most of you recommend the foam insulation. However, so far I have found only one contractor in the Pittsburgh area offering this for Gorell, Soft-lite, and Sunrise. I have only spoken with three contractors and I am wondering if my area is an anomaly or have I simply spoken with three unique people.

It seems to me that foam would do a better job in general.
It does, but....1. Foam is significantly more expensive than fg. 2. Many "old-timers" are set in their ways and resistant to change. Can you get a good installation without foam?:Yes, however, foam would unquestionably provide the superior installation. I'd also suggest that many times (there are exceptions-of course) the issue of whether or not a company uses foam is a pretty good barometer on their commitment to using the the highest quality, most-innovative, products and installation techniques.

Skydawggy.
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Re: Spray Foam vs Fiberglass insulation??

#13 Post by Skydawggy. »

Yes, having foam is as critical as selecting a window. That huge 1/8 of an inch gap around the window must be filled with closed cell foam or your windows will leak air like crazy. It won't matter whether you got a top notch install and the installer carefully caulked the windows so no air will leak. And while we are at it, don't buy any window that doesn't have foam in the frames or sashes too, because we all know that it makes no sense to have insulation in your walls but none in your windows. And don't even consider a window that uses any type of metal in the spacer. Nor should you purchase a window with a .30 U-factor when many manufacturers make them at .28. I think any manufacturer that can't get their U-factor below .30 has fallen behind the times doesn't have a commitment to producing the best window they can by using the the highest quality, most-innovative, products and manufacturing techniques. All this together adds up to huge savings[/sarcasm off]

tommyj
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Re: Spray Foam vs Fiberglass insulation??

#14 Post by tommyj »

Image

Skydawggy.
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Re: Spray Foam vs Fiberglass insulation??

#15 Post by Skydawggy. »

tommyj wrote:Image
:lol:

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