Basement Mystery-insulation/vapor Barrier - Carpentry - DIY Chatroom Home Improvement Forum


Go Back   DIY Chatroom Home Improvement Forum > Home Improvement > Carpentry

CLICK HERE AND JOIN OUR COMMUNITY TODAY...IT'S FREE!

Reply
 
Thread Tools Display Modes
Old 03-28-2010, 12:21 PM   #1
Member
 
Join Date: Jan 2010
Location: chicago
Posts: 110
Rewards Points: 75
Default

Basement mystery-insulation/vapor barrier


Hi,
I have a full conventional, poured basement with Fire escape/windowwell windows. The builder is out of business, and the county that did the inspections has been no help either. The insulation on my basement walls is a mystery.

Basically I have a generic-looking white plastic-faced yellow fiberglass insulation. The backing is unfaced, yellow insulation directly on the concrete.

It might be certanteed...but even on their website they have both; vapor barrier and porous.

So is there a way to figure out what I have? The code was a requirement to have R11 on the basement walls. I would like to keep it vs tearing it off.
Also, the insulation is installed from the top to about 6 inches from the floor/wall intersection. The seams are taped, not sure to act as a vapor barrier or just to make the seams nice and neat.

I know foam board or sprayed is a better method, but since it is installed directly onto the concrete by essentially a hilti gun...I figured I might as well use it.

Can I simply make several cuts with a utility knife thru the plastic to ensure vapor permeability?

Any suggestions!?

Thanks!

Advertisement

bergerdude is offline   Reply With Quote
Old 03-28-2010, 02:33 PM   #2
Member
 
Join Date: Mar 2007
Location: Long Island, NY
Posts: 9,519
Rewards Points: 2,000
Default

Basement mystery-insulation/vapor barrier


What is done is regionally dependent. There are no universal installation methods.
Where are you located?
Ron

Advertisement

Ron6519 is offline   Reply With Quote
Old 03-29-2010, 12:26 PM   #3
Member
 
Join Date: Jan 2010
Location: chicago
Posts: 110
Rewards Points: 75
Default

Basement mystery-insulation/vapor barrier


Im around Chicago.

I can either leave the insulation up....or take it down and slice into the correct size and use it in the wall.

Leaving it up would be easier of course.
bergerdude is offline   Reply With Quote
Old 03-29-2010, 10:28 PM   #4
Registered User
 
Join Date: Mar 2009
Posts: 9,993
Rewards Points: 2,052
Default

Basement mystery-insulation/vapor barrier


Kind of like this? http://www.buildingscience.com/docum...ts?full_view=1

Be safe, Gary
__________________
If any ads are present in my answer above, I do not condone/support/use the product or services listed, they are there against my permission.
Gary in WA is offline   Reply With Quote
Old 03-30-2010, 01:12 AM   #5
Member
 
Join Date: Jan 2010
Location: chicago
Posts: 110
Rewards Points: 75
Default

Basement mystery-insulation/vapor barrier


yes I have seen that....it still doesnt answer my questions
bergerdude is offline   Reply With Quote
Old 03-30-2010, 09:08 PM   #6
Registered User
 
Join Date: Mar 2009
Posts: 9,993
Rewards Points: 2,052
Default

Basement mystery-insulation/vapor barrier


Insulations, Sheathings and Vapor Diffusion Retarders Sorry. Read from figure #9 through to figure #10, and notice those pictures. Another good study : http://www.swinter.com/services/docu...Insulation.pdf I would remove the batts from against the concrete and replace with foam boards.

"Can I simply make several cuts with a utility knife thru the plastic to ensure vapor permeability?" ------ No. “Furthermore, the amount of vapor which diffuses through a building component is a direct function of area. That is, if 90 percent of the building envelope area is covered with a vapor diffusion retarder, then that vapor diffusion retarder is 90 percent effective. In other words, continuity of the vapor diffusion retarder is not as significant as the continuity of the air flow retarder. For instance, polyethylene film which may have tears and numerous punctures present will act as an effective vapor diffusion retarder, whereas at the same time it is a poor air flow retarder.” http://apps1.eere.energy.gov/buildin...rica/35793.pdf

Do I need to install a vapor retarder? If so, where should they be placed?
Vapor retarders are generally required by building codes in most climates. Vapor
retarders are generally placed on the warm-in-winter side of the wall. This is the inside
of the wall in most climates. The use of vapor retarders in the southern states is optional
in some cases and in some applications should be located on the outside of the building.
For hot humid climates the North American Insulation Manufacturers Association
(NAIMA) make the following recommendations; “A reasonable recommendation for
humid (Gulf Coast) and cooler "fringe" areas is: Use either an interior or exterior side
vapor retarder with moderate permeance. Inset stapled (or unstapled) kraft facing, with a
permeance of about 1 perm, meets this requirement; foil and polyethylene do not; their
permeance ratings are much lower.” http://www.insulating-products.com/p...lation_FAQ.pdf


Be safe, Gary
__________________
If any ads are present in my answer above, I do not condone/support/use the product or services listed, they are there against my permission.
Gary in WA is offline   Reply With Quote
Old 03-30-2010, 09:36 PM   #7
Member
 
Join Date: Mar 2010
Location: New York
Posts: 1,764
Rewards Points: 42
Default

Basement mystery-insulation/vapor barrier


You are describing what they are calling a diaper. Unfaced fiberglass with a plastic sheet that holds vapor in the insulation. I would be inclined to take out a few sample sections first to see if you have a moisture issue but that is not a professional opinion.

Last edited by Jim F; 03-30-2010 at 09:39 PM.
Jim F is offline   Reply With Quote
Old 04-01-2010, 01:08 PM   #8
Member
 
Join Date: Jan 2010
Location: chicago
Posts: 110
Rewards Points: 75
Default

Basement mystery-insulation/vapor barrier


Quote:
Originally Posted by GBR in WA View Post
Insulations, Sheathings and Vapor Diffusion Retarders Sorry. Read from figure #9 through to figure #10, and notice those pictures. Another good study : http://www.swinter.com/services/docu...Insulation.pdf I would remove the batts from against the concrete and replace with foam boards.

"Can I simply make several cuts with a utility knife thru the plastic to ensure vapor permeability?" ------ No. “Furthermore, the amount of vapor which diffuses through a building component is a direct function of area. That is, if 90 percent of the building envelope area is covered with a vapor diffusion retarder, then that vapor diffusion retarder is 90 percent effective. In other words, continuity of the vapor diffusion retarder is not as significant as the continuity of the air flow retarder. For instance, polyethylene film which may have tears and numerous punctures present will act as an effective vapor diffusion retarder, whereas at the same time it is a poor air flow retarder.” http://apps1.eere.energy.gov/buildin...rica/35793.pdf

Do I need to install a vapor retarder? If so, where should they be placed?
Vapor retarders are generally required by building codes in most climates. Vapor
retarders are generally placed on the warm-in-winter side of the wall. This is the inside
of the wall in most climates. The use of vapor retarders in the southern states is optional
in some cases and in some applications should be located on the outside of the building.
For hot humid climates the North American Insulation Manufacturers Association
(NAIMA) make the following recommendations; “A reasonable recommendation for
humid (Gulf Coast) and cooler "fringe" areas is: Use either an interior or exterior side
vapor retarder with moderate permeance. Inset stapled (or unstapled) kraft facing, with a
permeance of about 1 perm, meets this requirement; foil and polyethylene do not; their
permeance ratings are much lower.” http://www.insulating-products.com/p...lation_FAQ.pdf


Be safe, Gary
I appreciate that, and I didn't mean to seem rude earlier.
My basement "diaper" stop about 6 inches from the floor. It is stapled around the windows and such.

Does it make a difference if the "finished" basement room is adjacent to an unfiniished storage area? In other words, would it be beneficial to keep the the back of the wall space open where the drywalled area stops.

There will be doors leading to the storage area, bear with my crude diagram.

Either way does the "diaper" need to come down even with the walls left open to the storage area??
[IMG]file:///C:/DOCUME%7E1/HP_ADM%7E1/LOCALS%7E1/Temp/moz-screenshot-4.png[/IMG]
Attached Thumbnails
Basement mystery-insulation/vapor barrier-diy.jpg  

Advertisement

bergerdude is offline   Reply With Quote
Reply


Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
At a crossroads in my basement project - waterproofing help needed callisto9 Building & Construction 35 10-28-2010 03:01 AM
Thoughts and ideas basement finishing and HVAC creamaster HVAC 1 03-10-2010 08:46 PM
Adding Subpanel for Basement - Few Questions mindle Electrical 28 01-07-2010 09:49 AM
Insulating basement ceiling - your recommendations? jtmann HVAC 8 11-24-2009 05:44 PM
can anyone identify this mystery basement plumbing??? pkovo Plumbing 6 03-08-2009 11:20 PM




Top of Page | View New Posts