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4 Answers

Polyiso Interior Insulation in Old Barn

I am starting on the second floor remodel of a 19th c. barn, and I'm considering using polyiso panels on the interior side. I've never used rigid and non-rigid insulation in conjunction, and I have a few questions.

The Basics:

This will be a storage space and workroom. The barn is in Maine. The barn exterior is original horizontal siding (which I may be replacing but not until summer) over original vertical 1x sheathing (with some gaps). This is attached directly to the frame of the barn, which is open on the inside and roughly 5" deep.

My Plan:

Asked By ThreeBirdFarm | Mar 22 18
1 Answer

Best way to insulate an existing pole barn that has metal siding and no wrb?

I have read many versions of this question (as well as many answers) on your site, and at this point I am looking for the most current responses and solutions to this age old problem. I am well aware of the inherent pitfalls associated with pole buildings but it is what i have and i am hoping to make the best of it.

Asked By Darryle Mendes | Mar 21 18
16 Answers

Should I vent a cathedral truss with a metal roof and foam insulation?

Using 2 layers of 2 “ Poly foam under the roof strapping then 2” air space and 1 more 2” Poly going across the top chord of truss to eliminate thermal bridging.

Asked By User-7034059 | Mar 10 18
7 Answers

Open cell spray foam under roof deck

A couple years ago we converted our vented attic to an unvented/conditioned attic with open cell spray foam applied under the plywood roof deck. We even installed an HVAC vent in the attic to keep the RH in the attic similar to the rest of the house. So far everything seems fine but I've recently read about issues with open cell under roof decks, including one article on this website. I live in climate zone 4, asphalt roof over plywood deck. Should I be concerned about having a wet roof deck?

Asked By Michael Mohr | Feb 7 17
4 Answers

No basement, want no interior VOCs, looking for low cost exterior climate control for paints, caulking and their ilk

I have nearly finished construction of our slab-on-grade house in zone 5 MA.

We have neither a basement, an attic nor garage. All the interior space shares the same air, with a tiny utility room. Interior air quality is important -- the house is all pine and cement. No plywood, no mdf, no chipboard, no OSB; essentially, no glues or resins. No combustion equipment .. all electric. Very few plastics, no carpets, no paint. What we breathe matters.

Asked By Kenneth Gartner | Mar 23 18
6 Answers

Basement vapour barrier


Asked By user-6994354 | Feb 17 18
2 Answers

Necessity of smart vapor retarder in Tiny House on Wheels in Zone 4A?

GBA community,

Asked By Cam Kerr | Mar 23 18
5 Answers

Does interior ceiling strapping cause a moisture issue?

I am in climate zone 6 and am currently concerned about my insulation strategy on
a remodel of a 100 year old kitchen.The customer wants cathedral ceilings so I am trying to do my best

Asked By Eric Anderson | Mar 22 18
14 Answers

Outdoor mini split condenser unit in an insulated ventilated box indoors?

I need to cool (summer) and heat (winter) one room which is total 16.7 x 12.2 x 8.5 feet (1731 cubicfeet) (5.10m x 3.70m x 2.6m). I would need a unit between 2 or 3 tons.

Unfortunately I am not able to install the outside condenser unit outside of the building. That is the reason why I need expert advice.

Asked By purpleAnt | Mar 20 18
2 Answers

Rockwool (Roxul) sheet sizes. [2' x 4' or 4' x 8']

We're about to start insulating the foundation walls with Rockwool/Roxul Comfortboard IS 80.

In all of my reading I have seen theses boards come as 2' x 4' boards. Even then I have read of some difficulty handling.

Our supplier is suggesting 4' x 8' boards of the same product, but I am worried that this will be even more difficult to work with.

Has anyone here worked with Comfortboard for vertical exterior insulation and have experience witht he 2' x 4' or 4' x 8' board sizes? Any thoughts on the matter?

Asked By Ethan T ; Climate Zone 5A ; ~6000HDD | Mar 22 18
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