Insulating garage with recycled insulation

[rgviewer]

I have a 24 x 24 garage that also has a really nice furnace in it. I can get the temps to above 70 no problem when it is -5 outside. My garage currently is not insulated, nor is it drywalled so when I heat it, I use a lot of fuel. Recently I got a lot of used insulation off of craigslist, enough to do all the walls and part of ceiling. It is mostly craft faced bat insulation and most of it is 16" x 48". My walls are 24" x 96".

I don't have the money now for new insulation and limit my time in the garage now. I started piecing the insulation together to fill my wall cavities But since there is now a vertical seam and a horizontal seam where they are pieced together I was worried about it loosing the R value..

So my idea was to piece together the kraft faced insulation and then cover the wall with 6 mil plastic vapor barrier. I figured this would improve everything, help with warm air escaping and cold air coming into garage and as an added bonus, it holds the insulation together until I drywall it.

I only have half of one wall done but today when I was working out there I saw moisture trapped inside the plastic vapor barrier between plastic and the kraft faced paper. I don't want a mold problem but not sure what is the best way to make this work. Should I not use the plastic vapor barrier or is it that now that I have both plastic and kraft that is my problem.
Any suggestions.

 

[kd3pc]

you can only have ONE vapor barrier....with kraft face and plastic, that makes two....

One idea is to remove all the kraft facing, and just go with the plastic...

best of luck

 

[rgviewer]

That was kinda what I was thinking, now that I see moisture. I just wanted someone's opinion. I wasn't sure if it was acceptable to use plastic but figured it would hold things together. I never thought about taking off the kraft paper. Will I loose much if any R-Value if I remove the paper backing as long as I use a 6 mil plastic.

I would almost think it would be better as it will also block air flow. I can hang it from top to bottom and span it at least 8 ft wide. Also I am stapling the plastic to 2 x 4. Is this the correct way to do it?

Thanks for any and all input

 

[ArkTinkerer]

Just take a razor knife to the Kraft face. A number of slits spread across the surface will let it breath.