# Can I frame over the builders insulation in the basement?



## ChaoticBliss (Oct 17, 2009)

Hi All,

I am planning on finishing a portion of my basement and I was wondering if I could leave up the builders insutation (pink insulation with plastic over it attched directly to the concrete covering about 60% of the wall) and frame over it? My plan was to use the rigid foam insulation to cover the bottom half of the wall, seal that to the existing insulation and then put my framing up against that. I know I will loose a little floor space but I am trying to save on some costs. Will this be sufficient? I find the basement warm enough as it is now.

Thanks


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## Gary in WA (Mar 11, 2009)

http://www.buildingscienceseminars.com/presentations/bbbd2008/Basements-New&Retrofit.pdf

http://www.buildingscience.com/docu...rol-for-new-residential-buildings?full_view=1
Be safe, Gary


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## Scuba_Dave (Jan 16, 2009)

Do you have a picture of this?
Pink fiberglass is not supposed to go right up against cement due to water vapor coming thru the cement


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## rustyedge (Aug 30, 2009)

My basement had insulation on about 60% of the wall as you describe but did not have plastic over it. I framed right up to it and did not add insulation to the bottm 40%. Basement has been finished 3 years now with no problems. I do have a couple areas with access so I can check behind the walls and so far everything has been OK. Maybe there is enough ventilation back there to keep enough air moving.


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## ChaoticBliss (Oct 17, 2009)

Scuba_Dave said:


> Do you have a picture of this?
> Pink fiberglass is not supposed to go right up against cement due to water vapor coming thru the cement


Here is a picture:

http://s278.photobucket.com/albums/kk114/GT666GT/?action=view&current=DSCN0793.jpg








http://i278.photobucket.com/albums/kk114/GT666GT/DSCN0793.jpg

The insulation is up against the concrete with the vapour barrier over top. I think this is to code in Ontario, Canada. I am to leave this and up and frame up to it since I find the basement warm enough as it is.

Thanks


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## Scuba_Dave (Jan 16, 2009)

The problem will be mold that will grow behind the sheetrock
That's a problem you will not see unless it gets really bad


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## ccarlisle (Jul 2, 2008)

Yup, that looks like code all right - minimum code,,,and we all know how good that is don't we?

How'd they get that fibreglass into the diaper?

There are some very interesting combination EPS/OSB or plywood panels now that you put directly against the concrete walls...see InsoFast


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## Scuba_Dave (Jan 16, 2009)

A better method is foam board up against the cement, then the framing
Any water vapor coming thru the cement will be trapped by the plastic
The water will have no-where to go
In dry areas this may not be a problem

But its better to avoid the problem 1st then have to tear walls apart to fix a problem


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## DIYChic (Oct 17, 2009)

*Here's pictures of our basement with SPRAY foam*

We framed our wall first... about an inch away from the wall and used treated 2x4 at the bottom in case of water into the basement.


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## Gary in WA (Mar 11, 2009)

You apparently do not understand the window egress thing. The window needs to be* 44" above the finish floor to the opening,* so children and adults can escape in case of fire, through an clear opening. The three windows pictured are the only means of escape from the basement if a fire is in the stairwell? They are* not forty-four inches or less above the floor* to the opening. Why would you put your family and friends at such risk after all the minimum safety code information given to you on windows and egress? 

Hint: the back of the studs will pick up moisture from the concrete as there was no thermal break by spacing the studs from concrete for insulation. 2x4 studs have a R-value of 4.38 (with 33 studs- 1-1/2" wide =50" of wall with r-4.38 insulation) that's a *4' wide x 8' tall * hole insulated to less than R-5, or the same as *1-1/4" *of fiberglass batting.
You could still install rigid foam board and a v.b. on the face for your very cold climate, but the studs would not dry to the inside....
Be safe, Gary


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## ccarlisle (Jul 2, 2008)

_"You apparently do not understand the window egress thing..."_

I didn't figure the poster actually built the house, nor did she say that she did. So are we saying the house isn't to code? :no:

IMO she did fine, leaving a one-inch gap between the studs and the concrete and filling in with foam. The foam provides the thermal break behind them...:wink:


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## Gary in WA (Mar 11, 2009)

Whoops! I missed the 1" away from concrete. Void the thermo barrier talk in my last half. But, ask your Building Department when finishing even a portion of your basement if you need egress. Around here you do, maybe it's a local thing.... The code says habitable space, page 19, under Basement egress IRC 310.1 Canada Code Check Building, free: http://rapidlibrary.com/index.php?q=national+building+code+of+canada
Be safe, Gary


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## ccarlisle (Jul 2, 2008)

Egress - from, for example, basements - is one area where fire codes enter into the Buildiing Code mess, to make existing differences between all the codes even more muddy. 

And remember the IRC was only adopted in the early 2000's I think and I have no information form the OP as to when her house was actually built and therefore which code it was built under. 

If the OP's house is in the province of Ontario, then that means "egress" was even less relevant - as the Canadian IRC doesn't put as much emphasis on egress as you in the US do. To say nothing of fire codes...

Having said that, my house in Montreal was built in 1960 and one window in the basement is exactly at 44"; not all - but at least that one.:huh:


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## ChaoticBliss (Oct 17, 2009)

Scuba_Dave said:


> A better method is foam board up against the cement, then the framing
> Any water vapor coming thru the cement will be trapped by the plastic
> The water will have no-where to go
> In dry areas this may not be a problem
> ...


 
In an effort to save cost, could I peel back the stuff the builder has put up, install the foam board against the concrete and then put the builders stuff back on top fo the foam and the frame over that? This would save me having to rip it all down (and dispose of it somehow) and put in new batt insulation.

Thanks


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## Scuba_Dave (Jan 16, 2009)

Yes I think that is do-able
And much better then leaving the fiberglass against the cement
You don't need really thick stuff
Just something to stop the water vapor & protect the fiberglass from water intrusion

Possibly you woud never have a problem, with the fiberglass against the concrete
But its a lot easier to spend a little time & $$ & do it right, rather then have to rip it out & do it over


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## Gary in WA (Mar 11, 2009)

1.3.5. Limited Application to Existing Buildings
1.3.5.1. Alterations and Repairs
"1) This Code applies to the part of an existing building that is altered and repaired.
If, in the opinion of the authority having jurisdiction, the alteration will affect the degree
of safety of a part of the existing building not altered or repaired, those parts of the existing
building shall be improved as required by the authority having jurisdiction.
2) If a building is altered or repaired, the level of life safety and building performance
shall not be decreased." From: http://web2.gov.mb.ca/laws/regs/pdf/b093-127.06.pdf

Ask your* local* Building Department, as I said earlier. Better to be safe than sorry.....
Be safe, Gary


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## sbmfj (Oct 3, 2009)

Water vapours have always confused me. 

So, in this example, youd...
1. affix the blue styrofoam boards to the cement. do you use tapcoms, or glue it?
2. Plastic sheets, aka vapour barriers, over the styrofoam.
3. Pink insulation stuff over the plasic
4. then frame. again, would you use tapcoms to get to the cement wall/foundation?

Thanks!!


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## ccarlisle (Jul 2, 2008)

Depends...the OP is in a cold zone where vapour barriers go on the warm side of the insulation. So:

1: yes, stick the foam with glue or use uprights and tapcons. Tape the joints.
2. then the other insulation - but here it'll be messy.
3. then free-standing stud wall, not attached to cement but to floor and ceiling joists.
4. then the plastic vb


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## sbmfj (Oct 3, 2009)

whats step 2, the messy insulation?
Never thought of the free standing wall stud ...Do you use an L bracket to attach the 2x4 to the floor, or another tapcom?

Im in MTL too. NDG to be exact. Maybe one day you can help me out if Im in a jam..lol

So you have suggested the vapour barrier (plastic) last. So, I would screw the drywall over the plastic?

and in a north eastern climate such as ours (Quebec, Canada), youd always want to put the vapour barrier (plastic) last, as a final shield?

Thanks!


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## ccarlisle (Jul 2, 2008)

hello from Pointe-Claire...

Here's the deal. It just looks to me that the OP has the bare minumum code for insulation and that meant blown in fibreglass surrounded like a diaper by the plastic sheet which holds everything in with tape. Now as soon as you take off the tape you'll have a mess of pieces of fibreglass at your feet...

If she wants to put more styrofoam, she'll have to take off the plastic thereby releasing all the fibreglass pieces to the ground - what a mess! 
And all stud walls in the basement mustn't touch the concrete or they'll transmit the cold through them, So they're attached to the floor with tapcons and throught the joists at the top with nails/screws. Put a layer of pink styrofoam rolls under all wood touching concrete. 

The vb is last, stapled to the studs and taped everywhere...drywall goes over that into the studs.

Drywall/plastic vb/studs/insulation/concrete up here in that order from the inside of the room.

PM me anytime for help.


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## ChaoticBliss (Oct 17, 2009)

ccarlisle said:


> hello from Pointe-Claire...
> 
> Here's the deal. It just looks to me that the OP has the bare minumum code for insulation and that meant blown in fibreglass surrounded like a diaper by the plastic sheet which holds everything in with tape. Now as soon as you take off the tape you'll have a mess of pieces of fibreglass at your feet...
> 
> ...


 
I actually did a test last night and cut open the diaper, the insulation under it is not blown in, it is solid pink insulation so it won't be as messy as I thought.


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## user64621 (Oct 16, 2009)

i personally never have tested vapor emissions that would come through a poured concrete wall, but has anyone ever done a calcium chloride test? 
I wouldn't think that it would be that bad, with proper exterior damp proofing + -usually- foam insulation on the exterior? (which doesn't sound like the case here)


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## Salem747 (Oct 16, 2009)

Have you looked into having it sprayed with foam? that would solve all of your problems in one foul swoop!


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## ccarlisle (Jul 2, 2008)

Phew! Thanks Chaotic for putting me straight...I looked and looked and all I saw was... fibreglass! So OK then, my eyesight is poor.

Good then it won't be a mess. 

Flip, my eyesight is really bad now I can't even find the picture! LOL


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## Gary in WA (Mar 11, 2009)

ccarlisle said:


> Egress - from, for example, basements - is one area where fire codes enter into the Buildiing Code mess, to make existing differences between all the codes even more muddy.
> 
> And remember the IRC was only adopted in the early 2000's I think and I have no information form the OP as to when her house was actually built and therefore which code it was built under.
> 
> ...




Just wanted to clarify a few things for any Canadians reading your statements about code. The site I stated has the Building Codes of Canada for free to download. Turns out, they are the exact same codes we use here in the States.:huh:What a hoot! This condensed cheat book, called Code Check Building is valuable for the minimum safety standards required. http://rapidlibrary.com/index.php?q=national+building+code+of+canada

Page 22 of the booklet has all egress codes for doors, decks, guardrails, bedroom egress, bedroom window sizes, and basement egress, not muddy at all. They are really handy to have, but you need to download them to see them. :yes: Remember this is an earlier book, the most recent one may have stricter changes and your local Providence may have addition ones. 
Be safe, Gary


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## ccarlisle (Jul 2, 2008)

Thanks for those links, Gary...:thumbsup:


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## sbmfj (Oct 3, 2009)

thanks for the explanations!!


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## silvergs (Oct 5, 2009)

ccarlisle said:


> hello from Pointe-Claire...
> 
> Here's the deal. It just looks to me that the OP has the bare minumum code for insulation and that meant blown in fibreglass surrounded like a diaper by the plastic sheet which holds everything in with tape. Now as soon as you take off the tape you'll have a mess of pieces of fibreglass at your feet...
> 
> ...


Hi ccarlisle, that was an excellent post and by coincidence I am in the exact same situation as the OP.

I just wanted to quickly clarify your explanation above.

Order of tasks to finish framing:
1. Take off the VB from the existing insulation
2. Leave existing insulation as is - what would hold it up (after I have taken off the VB)- assuming the existing VB is holding it up?
3. Add more insulation to fill up the bottom portion
4. Install frame against the insulation - how close to it can the studs be? pushing against it closely? Please be specific.
5. Install wiring
6. Install VB
7. Drywall

One last question regarding the tapcons - I guess this means I just need to get the appropriate carbide drill and don't need to rent one of the nailer guns - that shoot nails into concrete? That would be awesome if I didn't have to. What size of bit and nail do you recommend?

Have I missed anything?

Here's the thread I started with tons of pics and a plan I drew up in Visio - http://www.diychatroom.com/f19/not-...t-my-motivation-will-make-up-some-tips-54470/


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## silvergs (Oct 5, 2009)

I wanted to bump this thread up in the hopes that ccarlise will see it.


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## ccarlisle (Jul 2, 2008)

Well, I can tell you what I like to do in new basements: 2" of styrofoam board glued to the concrete wall, taped and foamed into place. Then a stud wall tapconned into the floor and screwed into the ceiling joists; at this time run the wiring. Then either pink or Roxul insulation between the studs. That's it. No vb... then gyproc.

Now in the case of the OP, you have that pink fibreglass in the way. Sure it's minimum code but it'll just get in the way, so remove it. They only need that plastic diaper vb becasue there is no foam thermal break on the walls...it's one or the other: thermal break OR vb.


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## silvergs (Oct 5, 2009)

ccarlisle said:


> Well, I can tell you what I like to do in new basements: 2" of styrofoam board glued to the concrete wall, taped and foamed into place. Then a stud wall tapconned into the floor and screwed into the ceiling joists; at this time run the wiring. Then either pink or Roxul insulation between the studs. That's it. No vb... then gyproc.
> 
> Now in the case of the OP, you have that pink fibreglass in the way. Sure it's minimum code but it'll just get in the way, so remove it. They only need that plastic diaper vb becasue there is no foam thermal break on the walls...it's one or the other: thermal break OR vb.


Hi ccarlise, thanks for the clarification.

In what sizes does the styrofoam come in? 
What specific kind of glue do I need to glue it to the wall?
What do you mean by "foamed into place"?
How are the bottom plates treated? Do I just wrap those in thick plastic sheet or do I need treated lumber?
Why are both the styrofoam and the insulation needed? Isn't the styrofoam enough insulation?

And lastly, this means that I can then use the existing insulation (assuming I have taken it off) and use it now between the studs?


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## ctkeebler (Nov 8, 2009)

Scuba_Dave said:


> A better method is foam board up against the cement, then the framing
> Any water vapor coming thru the cement will be trapped by the plastic
> The water will have no-where to go
> In dry areas this may not be a problem
> ...



Dave this is XPS insulation correct? How thick is it. The stud wall is directly infront of the insulation without any gap? Are you going to fill the void before the dry wall is attached. Also how are the board attached to the concrete wall?

Thanks sorry for all the questions, but Im looking to do this exact thing and want to do it right.

Tom


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## Scuba_Dave (Jan 16, 2009)

Actually that's just a pic I pulled off the Internet
I haven't looked into the specific rigid foam I will use
That project is probably 1-2 years away at least


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## ctkeebler (Nov 8, 2009)

Scuba_Dave said:


> Actually that's just a pic I pulled off the Internet
> I haven't looked into the specific rigid foam I will use
> That project is probably 1-2 years away at least


Okay thanks. You dont happen to recall where. I need to describe what I want to do to the inspector.

I appreciate the help.


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## Scuba_Dave (Jan 16, 2009)

Its from

http://www.homeconstructionimprovement.com

If you right click & select properties of the picture it shows you the location


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## Gary in WA (Mar 11, 2009)

If you want a picture of it in pink, page 13, photo #8: http://www.eere.energy.gov/buildings/building_america/pdfs/db/35017.pdf
That will explain it all to them as well. 
Be safe, Gary


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