Spray foam insulating headers in basement?

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  #1  
Old 10-07-05, 01:17 PM
Peethree
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Question Spray foam insulating headers in basement?

Hi, I have received a quote for upgrading insulation in my home (I am a limited DIY-er and this is not something I plan to do myself)

House is 19 yrs old, 2 story brick structure approx. 3100 sq ft, unfinished basement near Toronto, ON

We have no plans to finish the basement in the next 4-5 years. There is currently yellow batt insulation framed in halfway down the walls.

The contractor is recommending that we insulate only the basement headers with 2 component spray foam insulation. He will then cover the foam with R12 fibre glass batts and install vapour barriers onto the headers.

He says this will make far more difference then finishing the insulation down the other half of the walls.

Can I please get some additional opinions on this?

Thanks in advance,
Peeth.
 
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  #2  
Old 10-11-05, 07:36 PM
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Join Date: Feb 2005
Posts: 68
Originally Posted by Peethree
Hi, I have received a quote for upgrading insulation in my home (I am a limited DIY-er and this is not something I plan to do myself)

House is 19 yrs old, 2 story brick structure approx. 3100 sq ft, unfinished basement near Toronto, ON

We have no plans to finish the basement in the next 4-5 years. There is currently yellow batt insulation framed in halfway down the walls.

The contractor is recommending that we insulate only the basement headers with 2 component spray foam insulation. He will then cover the foam with R12 fibre glass batts and install vapour barriers onto the headers.

He says this will make far more difference then finishing the insulation down the other half of the walls.

Can I please get some additional opinions on this?

Thanks in advance,
Peeth.

eesh get a second opinion insuating the floor wih foam is great but keep in mind that it is also a great way to hide a lot of mistakes (i.e. wiring so make sure it in isspected b/f you foam it) also fibre glassing with foam is not usually mixed with spray foaming as VB with spray foam in usually redundant. Furthermore the basement has your gas and water utilities in it and insulation the walls (if not already done must be done to ensure this is a warm space), It boils down to not going with what the frst guy says bring his plan down to
a permit office and see if they are willing to issue a permit...
 
  #3  
Old 10-11-05, 09:02 PM
Join Date: Mar 2005
Location: USA
Posts: 6,125
Spray foam insulating headers in basement?

Peeth -

You refer to headers, which are normally a beam over an opening in my way of thinking.

Is this what you are refering to? Or are you refering to the "rim joist" or "banding" around the house and sitting on top of the wood sill?

Could they be the joists, as Wonderslug appears to think they are?

Dick
 
  #4  
Old 10-14-05, 01:03 PM
Peethree
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Spray foam insulating headers in basement

Sorry for my terminology. I am referring to the very top of the basement walls, in between each joist supporting my main floor, all the way around the full perimeter of the basement (not the full length of space between each joist)

Also - would something like this need a permit? I had thought that it would not be required here as it's not a structural change and does not involve electrical / plumbing.

Thanks again for your help

Peeth.
 

Last edited by Peethree; 10-14-05 at 01:05 PM. Reason: spelling
  #5  
Old 10-14-05, 02:11 PM
Join Date: Mar 2005
Location: USA
Posts: 6,125
Spray foam insulating headers in basement?

You should definitely insulate the area between the joists at the rim joists (above the foundation). Fibeglass works well for this. This is a very practical, easy and and is positive way of reducing heat loss and should not require a code.

Canadian codes and methods are unique regarding basements (insulation and vapour barriers) and I have never been able to reconcile them with codes and standards elsewher in the world. In Canada, there seems to be a magical line on walls at grade and several feet below grade where everything inside the concrete wall changes. I have lived with -50 and been involved in Siberia construction and have never seem anything like it.

I would definitely not insulate the joist area between the basement and first floor just for insulation purposes.

Both batt insulation, like fiberglass, and foam work well. The only difference is that batt insulation can be applied by anyone and foams are usually licensed and patented can are only installed by the company SELLING and doing the work.

The short answer to your question is - I would install fiberglass between the joists at the top of the foundation and not get a permit since it is like putting in weatherstripping. I wouldn't worry about a vapor barrier there since it is not enough to worry about in comparison to the rest of the basement. Then I would plan for a proper method of finishing the basement in a few years.

Dick
 
  #6  
Old 10-17-05, 09:36 AM
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Location: USA
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Normally when others have replied, as a Moderator, I do not. Primarily because this is not my Forum and one of the duties of a Moderator is to promote responses by others. Furthermore, I readily admit that I do not know everything and I have learned more from this Forum than I have shared with it. However, since you have requested my input, I will accomodate you.

What is also very common on Forums is that the posters are not very well versed in the terminology of the trades. This leaves the people who reply to try and deduce what the poster is asking. This particular post exemplifies this. Where a reply indicated a lack of communication and then you replied with a much better description. This is by far the greatest benefit the members of this Forum receives.

Your confusion with this application stems from two schools of thought. The Old School supports WATER SHEDDING systems and the New School supports AIR TIGHT systems. While the two disagree on many aspects, there are common basics that are not disputed.

1. All materails absorb and expel moisture.

2. Hence all materials are given PERM RATINGS. An oversimplification of this is a material with a low Perm Rating will absorb and expel moisture slowly and one with a high Perm Rating will do it more quickly.

3. The Relative Humidity (RH%) of a material describes the ability of the material to retain moisture at different temperatures. Example a material can retain more moisture at a higher temperature than this same material at a lower temperature. To illustrate this is the condensation that occurs on a soda can during the summer. Air, which is an object because it has mass, that surrounds the soda can loses temperature because of the coolness of the can. This results in the air that surrounds the can to increase in RH%. To the point where the air that surrounds the can cannot hold the moisture it has and condenses that moisture on the can.

4. Equilibrium Relative Humidity (ErH%) explicitly implies that the rate of moisture absorbancy increases with rise in temperature and decreases with a drop in temperature. Though this does not define ErH%, for this purpose it applies.

While there are other factors to be considered here, the aforementioned should be sufficient for this explanation. Both schools have rules they follow. I will admit I am Old School. As such my position would be considered bias. I disagree with the application you described because it violates the 5 to 1 rule. This rule states that materials from inside (conditioned space) must have the lowest Perm Rating, example Vapor Barriers. And any material that follow the vapor barrier towards the outside must have a Perm Rating 5 times greater than the vapor barrier.

Even professionals make this mistake, the rule applies to all materials that follow the vapor barrier. In your application the fiberglass batts have a higher Perm Rating than the foam. Though arguably the vapor barrier retards the moisture flow, it still violates the 5 to 1 rule. Even though the foam does not violate it with the vapor barrier.

If you look closely at the 4 factors mentioned earlier. the materials closest to the inside have the greatest ability to to absorb moisture because of the high temperature and the materials furthest away towards the outside have the lowest ability to absorb moisture because of the lower temperature. This is the reason for the 5 to 1 rule.

It is good to note that regardless of my opinion or position on this matter, you must follow your local building code. Canada, along with many areas in the U.S., like Mininesota, follow the New School thought and their building codes reflect it.

If you are wondering about the insulation halfway down the wall, take the 4 factors mentioned earlier and throw in ground source water and capillary action. While it may be true that I probably know more about these applications than the people who install them, I do not consider myself an expert on them. As such you should contact them for their side. In the U.S. the oranization that supports such thought is www.aaba.org, the Association of Air Barriers of America or something similar to that. And Canada has a similar organization.
 
  #7  
Old 10-17-05, 11:17 AM
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Location: Ottawa, Canada
Posts: 857
Peethree,

What do you mean by upgrading your insulation?
What problem are you trying to resolve?
Why is there no insulation between the joists but it is present in between the studs in the basement?
 
  #8  
Old 10-19-05, 04:13 PM
Peethree
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basement insulation

Again, thanks to all for their input.

em69, to answer your questions...

There IS already batt insulation at the joist level - it has some black areas on it (not much), which he said was from air leakage - said he would remove it, install foam, then R12 batt on top of it. He also said don't bother insulating bottom half of basement walls as the foam at top would make far more of a difference.

Secondly, the problem I am trying to resolve (or, how this all began...)
I had an EnerGuide for Houses audit done and they recommended several improvements, including:

Attic: current = R15, increase to R50 to save 6% on energy costs (I've since heard from several sources that you need not go above R40 - so I'm getting quotes to get me up to R40)

Basement: current = R1, increase to R20 to save 12%

Space heating: current low efficiency, change gas furnace to high efficiency to save 30%

...and then misc. things like caulking, weatherstripping, etc. which I am undertaking myself.

I'm starting to wonder, should I just skip the basement and focus on my attic, furnace, caulking etc., THEN worry about insulating my basement further when we get around to actually doing any finishing / renos in the basement?

Compounding the problem is that I am having a h*ll of a time finding someone to even call me back about installing insulation - I have called 15 companies and only 2 have called me back and only 1 has quoted - everyone seems to be so busy with new home construction. (Then I think, how come this guy has time to quote if no one else does - is that a bad sign too?)

My husband is a fabulous cook and a great businessman, gotta love him, but right now oh how I wish he could be handier around the house

Peeth
 
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