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Does Fiberglass Batts Insulation works for windows?

Does Fiberglass Batts Insulation works for windows?

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  #1  
Old 11-18-11, 01:37 PM
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Does Fiberglass Batts Insulation works for windows?

1. I have 4 storm windows I need to insulate under $30. I only want a temporary solution for 1 year for a rental house and only needed it for not letting cold air in through windows [Everything else is already sealed]. It also doesn't matter for not seeing outside windows, since won't be doing on every window.

Therefore, does it make a difference if you use Fiberglass Batts to insulate the windows? The fiberglass Batts I will be using is the one you use for attic insulation and is RJ-30. [I checked the windows and it fits inside the space between the interior storm windows and exterior window]. It is like this one [not exactly that one but similar and it includes vapor barrier]:

R-30 10"T x 24"W x 48"L FSK25-Faced Fiber Glass Batts at Menards

2. Hence, will this be better for not letting cold air in through windows than using a foam board or foam panel or lumber [plywood, etc] or Drywall? If not, which should I use for a price range of under $30 for all 4 windows?
 
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  #2  
Old 11-18-11, 04:38 PM
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Have you considered the shrink wrap plastic instead?
 
  #3  
Old 11-18-11, 06:36 PM
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Originally Posted by Pulpo View Post
Have you considered the shrink wrap plastic instead?
I will do that also on all windows. However, I would like to know the answer to my question meaning will applying fiberglass will be effective or not for reducing cold air coming from outside the house?
 
  #4  
Old 11-19-11, 06:02 AM
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I'm sure that it will reduce heat loss but I can't say by how much. It's not so much stopping the cold from entering as it is stopping the heat from leaving.

Secondly, if the house is going to be occupied during the winter, you don't want particles of fiber glass floating in the air. It is not healthy at all.
 
  #5  
Old 11-19-11, 06:37 AM
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You don't say where you live but if in a cold climate you could damage the home by putting fiberglass batts against the windows.

You not only will insulate the house from the cold glass you will insulate the glass from the warm air in the house.
The insulation will cause the surface temperature of the glass to get colder and then it will collect moisture and frost which will melt and run down where the widow meets the warm wall.
You could try the fiberglass then covering it with well installed shrink wrap but the colder your climate greater the transfer to the glass will be.

Honestly, the insulation would be a bad idea, just go with the shrink wrap or do the shrink wrap and put the insulation on the outside.
 
  #6  
Old 11-19-11, 03:34 PM
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Originally Posted by Pulpo View Post
I'm sure that it will reduce heat loss but I can't say by how much. It's not so much stopping the cold from entering as it is stopping the heat from leaving.

Secondly, if the house is going to be occupied during the winter, you don't want particles of fiber glass floating in the air. It is not healthy at all.
It is going to be preoccupied for at least a year, but only putting fiberglass on 3 windows out of 7 windows. Should I still do it?
 
  #7  
Old 11-19-11, 03:43 PM
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Fiberglass will not stop airflow. I suspect that airflow will be a major concern on these windows. I would go for the foam board.
 
  #8  
Old 11-19-11, 03:48 PM
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Originally Posted by GregH View Post
You don't say where you live but if in a cold climate you could damage the home by putting fiberglass batts against the windows.

You not only will insulate the house from the cold glass you will insulate the glass from the warm air in the house.
The insulation will cause the surface temperature of the glass to get colder and then it will collect moisture and frost which will melt and run down where the widow meets the warm wall.
You could try the fiberglass then covering it with well installed shrink wrap but the colder your climate greater the transfer to the glass will be.

Honestly, the insulation would be a bad idea, just go with the shrink wrap or do the shrink wrap and put the insulation on the outside.
I live in clear lake, IA where average winter temp. is 22-26F daytime and 4-10F nighttime.

Would the shrink wrap will be enough to not let cold air in through the window? [I will put more than 1 on each window].

Also, what if I put fiberglass insulation only in 3 windows out of 7 windows, will that be okay than?
 
  #9  
Old 11-19-11, 03:56 PM
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Originally Posted by drooplug View Post
Fiberglass will not stop airflow. I suspect that airflow will be a major concern on these windows. I would go for the foam board.
1. You said fiberglass won't stop airflow, but are u sure about that since why is it than used on attic insulation? I thought it stops cold air from moving in from outside the house to inside the house?

2. can you please tell me specifically which foam board to use for windows, since i have no experience in that and having a hard time figuring it out!
 
  #10  
Old 11-19-11, 05:52 PM
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I would forget about the fiberglass in the windows for the reasons I mentioned. Besides that, fiberglass works in the attic because it stapled to the rafters. Just go with the plastic & leave it at that.
 
  #11  
Old 11-19-11, 07:43 PM
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I agree.
Do not put any kind of insulation against your windows.
It can cause damage if you do.

Use shrink plastic for windows and follow the instructions on the package.
 
  #12  
Old 11-19-11, 09:00 PM
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Originally Posted by Pulpo View Post
I would forget about the fiberglass in the windows for the reasons I mentioned. Besides that, fiberglass works in the attic because it stapled to the rafters. Just go with the plastic & leave it at that.
Okay i won't put any fiberglass however will a stack of cardboards be okay than? Or will the shrinkwrap [i will put both exterior and interior ones] be sufficient of removing any cracks or empty space for not letting cold air in through windows?
 

Last edited by baby327nd; 11-19-11 at 09:32 PM.
  #13  
Old 11-20-11, 06:07 AM
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The cardboard will be ok as long as it doesn't get soaked from the rain. Styrofoam would be better. (fanfold).
 
  #14  
Old 11-20-11, 08:32 AM
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You are either are not listening, are waiting for the answer you want to hear or are playing with us!

I'll say it again:
If you put insulation of any kind on the inside of the window the glass will frost up and water will run onto the wall.
Cardboard will act as insulation.

If you use shrink wrap plastic on the inside and tape it securely to the wall you will eliminate air leaks.
If you use insulation or cardboard put it on the outside but do not put plastic on it or you will trap moisture and it will frost.
 
  #15  
Old 11-20-11, 01:14 PM
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Originally Posted by GregH View Post
You are either are not listening, are waiting for the answer you want to hear or are playing with us!

I'll say it again:
If you put insulation of any kind on the inside of the window the glass will frost up and water will run onto the wall.
Cardboard will act as insulation.

If you use shrink wrap plastic on the inside and tape it securely to the wall you will eliminate air leaks.
If you use insulation or cardboard put it on the outside but do not put plastic on it or you will trap moisture and it will frost.
I did listen and changed my mind about putting fiberglass in the space between the storm and outside window. So, I will no longer do this method.

However, since you say cardboard is not okay either, than what about bubblewrap sprayed with water and attached between the 2 windows [same space where the fiberglass was suppose to be]? That will be okay than right?
 
  #16  
Old 11-20-11, 02:20 PM
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Why would you spray the bubble wrap with water?
 
  #17  
Old 11-20-11, 02:28 PM
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Originally Posted by Pulpo View Post
Why would you spray the bubble wrap with water?
Its for this method [but I am doing it between the windows also.]:
BubbleWrap
 
  #18  
Old 11-21-11, 01:45 PM
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can someone answer this question please:
what about bubble wrap sprayed with water and attached between the 2 windows [same space where the fiberglass was suppose to be]? That won't damage the windows right? [similar method as shown here BubbleWrap
 
  #19  
Old 11-21-11, 01:48 PM
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I'm sorry but this thread has gotten to the point where I have to ask:

Are you serious?
 
  #20  
Old 11-21-11, 02:14 PM
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I never heard of the bubble wrap idea but I guess it can't hurt. It's better than the fiberglass & cardboard ideas.
 
  #21  
Old 11-21-11, 02:14 PM
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Originally Posted by mitch17 View Post
I'm sorry but this thread has gotten to the point where I have to ask:

Are you serious?
Yes I am VERY serious and I just want to make sure I do it right. I did listen to the advice of not insulating with fiberglass between the windows. However, no one answered the question I really need the answer since I don't know it. So, can someone answer please about the bubble wrap method?
 
  #22  
Old 11-21-11, 02:23 PM
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I doubt anyone here has used bubble wrap on windows. As I said, it can't hurt so try it.
 
  #23  
Old 11-21-11, 04:10 PM
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The reason we don't think you are serious is you keep asking the same question and we keep giving you the same answer.
You asked about using fiberglass and we gave you our reason why we didn't think that would be a good idea.
You then asked about using cardboard as an insulator and we gave you exactly the same reason why we didn't think that would be a good idea.

Now, you are asking if you should use bubble wrap as an insulator!
I can give you the same answer again but would suggest that you read the info above.

I looked at the bubble wrap link and no mention was made of frosting.
They are either in a milder climate or their lifestyle does not tend to generate much moisture.

Why don't you try the bubble wrap and let us know how it goes.
Many would be interested in a real life review.
 
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