Replies

1. GBA Editor
   Martin Holladay | Dec 29, 2015 04:34am | #1

   Bill,
   The main difficulty when trying to insulate a pole barn is establishing an air barrier. The air barrier is necessary to separate the conditioned indoor air from the outdoor air.

   We need to know whether this pole barn has a dirt floor, a gravel floor, or a concrete floor.

   I hope you thought ahead and installed some type of material on the exterior side of your 2x6 studs before you erected the walls, but I'm afraid you may not have done that. Taped plywood or taped OSB on the exterior side of the 2x6 walls would have been ideal, but even housewrap would have been useful. Did you install anything like that before you raised your walls?

2. 
   fordv10 | Dec 29, 2015 04:01pm | #2

   hello martin. no i did not wrap the building, what ever needs to be done will have to be from the inside.. the ground was sprayed for bugs an clear plastic laid down,then concrete poured. the walls are just prurlins an sheet metal. i think that i have to a barrier up first,seal it then install roxul?.. i,m not sure at this point if i will dry wall it or put up osb. i guess it is what it is.an i,ll have to deal with it. tk u bill

3. GBA Editor
   Martin Holladay | Dec 30, 2015 07:02am | #3

   Bill,
   I'm glad that the pole barn has a concrete floor.

   There is still a contradiction in your description. In your original post, you wrote, "The walls have been framed up 2x6."

   Then, in your second post, you wrote, "The walls are just purlins and sheet metal."

   So which is it?

4. 
   fordv10 | Dec 30, 2015 09:20am | #4

   sorry for the confusion. the pole barn is built w/purlins then sheetmetal, 2x6 walls were installed after the roof an garage door were done. tks bill

5. GBA Editor
   Martin Holladay | Dec 30, 2015 09:54am | #5

   Bill,
   The best approach would be to cut the nails holding the bottom plates and top plates of the 2x6 framing, so that the stud walls can be lain down on the slab. That way you can sheathe the exterior side of the 2x6s -- I would use OSB with taped seams if I were doing the work.

   Once that's done, you can raise the walls again and secure the bottom plates and top plates.

   You really need an exterior air barrier on your walls, or it's going to be extremely difficult to insulate your walls.

   If you follow my advice, you'll be ready to insulate the stud bays any way you want -- with mineral wool, fiberglass, or spray foam insulation.

   Alternatively, if you don't have the stomach to cut nails and lay down your 2x6 walls, you can sheathe the interior side of the 2x6 walls with OSB, and then tape the OSB seams. Once this work is done, you can install one or more layers of rigid foam insulation on the interior side of the OSB sheathing, followed by gypsum drywall.

6. 
   wjrobinson | Dec 30, 2015 10:36am | #6

   I would insulate the inside, Martin's last idea

7. 
   fordv10 | Dec 30, 2015 04:13pm | #7

   pulling down the walls would really be tough so the walls will have to stay..rather than osb could i use a product like prodex or something similiar??? thanks for your help,it puts me on the right path tks again.....

8. GBA Editor
   Martin Holladay | Dec 31, 2015 07:22am | #8

   Bill,
   Prodex is a radiant-barrier product that is often marketed by dealers who exaggerate the product's R-value.

   Prodex Total is 13/64 inch thick -- that's less than 1/4 inch thick -- and has an R-value of less than R-1. As GBA noted in an article about this kind of scam, some Prodex Total marketers claim that the product has an R-value of R-16. This is a lie.

   To insulate your wall, you need real insulation with a measurable R-value, not a radiant barrier.