[Bull]

I'm finishing the downstairs of my new barn this summer as my first major project.

When built, the structure was wrapped in Tyvek (actually, a product called Vortec, but same basic idea.) The wrap seams were not taped. The exterior siding is shiplap, and my plan is to shiplap the inside, too, since it's easy and this is a BARN, so I want it to look like one.

Home Depot had R-19 rolls of insulation on sale, so I bought them. They are kraft-faced. Now, because the building has the Tyvek/Vortec, do I want to slit holes in the kraft paper? If I don't, will I essentially create a trap for water inside the walls, between the kraft paper and the house wrap? I also bought some 8 mil plastic that I had thought of installing over the insulation, to keep drafts out. But, now that I am thinking about it, won't that also cause a water trap issue?

Barn is not currently heated, but it will be someday.

Thanks for your guidance.

[stags]

Bull, the kraft batt/building wrap combo should be no problem; that's s.o.p. in many areas. I'm not familiar with the Vortek brand but Tyvek, and similar products, are designed primarily as air-infiltration barriers and will control, but not prevent, moisture passage.

I would avoid using poly film. While it can be effective in very cold climates it can also cause problems during humid summer months or if the installation is not meticulous. If you do, never use poly over another vapor barrier; remove the kraft paper altogether or buy unfaced batts.

If you want to seal out drafts, get some spray foam cans and seal all penetrations to the exterior/attic as well as window/door jambs (low expansion foam). Also, seal wire runs through the studs especially any that run through unheated areas.

[Bull]

Thank you, Stags, now I know how to proceed. I will leave the kraft paper intact and skip the poly installation.

Do the house wraps themselves help to reduce drafts as well, in that wind cannot just blow through cracks in the building's siding?

[stags]

Originally Posted by Bull

Thank you, Stags, now I know how to proceed. I will leave the kraft paper intact and skip the poly installation.

Do the house wraps themselves help to reduce drafts as well, in that wind cannot just blow through cracks in the building's siding?

Yes, assuming proper installation of a quality product. That is thier primary function - most air infiltration is wind driven; the rest is by suction (inside-out or outside-in) resulting from the temp and humidity differences caused by heating/cooling.

When you decide to add heat, be mindful of what you use. Low-budget systems like cheap propane heaters, etc. can add tons of humidity to the interior. Better to do your homework and spend a little more for quality results.

[Bull]

The barn builders did a pretty good job of the Tyvec/Vortec installation, although they didn't tape the seams. No one seems to, based on the new construction projects I've seen going up over the years.

Thanks again for the 411, I appreciate it.