Alternatively, and more environmentally friendly, would be to just build a more or less conventional wall assembly but do it from the outside in--start with a good WRB sealed to the girts and posts, then add sheathing (ZIP system osb installed inside-out would allow you to air seal effectively from the inside), then frame the wall and insulate the cavities.
It's hard to give solid advice because every pole barn is different, especially at places like the floor-to-wall and wall-to-roof intersections. Do you have a good architect, engineer or builder friend nearby who could look at what you have and provide advice?
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Thank you again Michael! I know without standing in the building and looking at what I am seeing, it can be difficult to advise. When you refer to the flash/batt as we discussed, are you referring to the issue with condensation accumulating because there is not enough spray foam. It is my (very basic) understanding that if you use spray of rigid foam against the metal siding it has to be thick enough to prevent that dew point from happening on the inside of your foam. In other words, I have to have enough spray foam or rigid foam to keep the warm air away from the outside air???
Unfortunately I don't have any help around here. I actually checked with a pole barn builder and they said the way they are insulating their buildings is just to place batts against the metal siding and closing it up. When I asked about the condensation issue and moisture ruining the fiberglass batts, he said there would be moisture, and that is how it is designed to behave. He said it would dry to the outside. He claimed the insulating companies are the ones doing it that way for them??? Maybe I'm wrong, but what little i know is fiberglass doesn't like moisture. In fact I always thought there were only a couple of types of insulation (aside from foam) that even tolerated moisture.
So that's what I am dealing with. I certainly appreciate the advice and knowledge you are sharing. I know pole buildings are very difficult to seal/insulate, and I know I will never get my pre-existing barn anywhere close to 100%. I just hope to put my best foot forward while trying to come up with a reasonable solution that fits within the parameters of my building. Darryle
Darryle, yes, you need to be concerned with moisture condensing on the interior surface of the foam. You can read more about it in Martin's article here: -minimum-thickness-rigid-foam-sheathing, and in a Fine Homebuilding article I wrote: -homebuilding/why-flash-and-batt-makes-sense.
While I often learn things from tradespeople--in fact, I make a point of trying to learn something new from everyone I work with--I do not put blind faith in their understanding of building science. I've put significant effort into learning about the fine points of building science for over ten years and still learn new things regularly. That said, if your siding is either corrugated or rib-panel (aka agricultural style), it does have built-in ventilation channels; if those are open at the bottom, and especially if they're also open at the top, they can provide a lot of drying potential. If they're closed with flashing or trim strips they may still offer some drying; it's hard to know without seeing it in person or at least a photo or drawing.
Most insulation materials do ok with a little moisture accumulation now and then. If fiberglass or cellulose get saturated, though, they can compress and lose R-value. Mineral wool is more rigid and dries readily after being loaded with moisture. Foam, either open-cell or closed-cell (same resin, different blowing agents and different finished qualities) is not affected by water, but open-cell foam can hold, and pass moisture, while closed-cell foam blocks water in all forms, as long as it doesn't crack. (The pole barns I'm familiar with are not the most rigid of structures.)
Foam in all forms has a higher carbon footprint than other insulation materials, especially standard closed-cell sprayed foam and XPS rigid foam (the blue, pink or green type), so like most green builders and designers I try to minimize my use of foam, but sometimes it's the only thing that will do the job both effectively and affordably.
Abstract:Soft-story wood-frame buildings have been recognized as a disaster preparedness problem for decades. There are tens of thousands of these multi-family three- and four-story structures throughout California and other cities in the United States. The majority were constructed between 1920 and 1970, with many being prevalent in the San Francisco Bay Area in California. The NEES-Soft project was a five-university multi-industry effort that culminated in a series of full-scale soft-story wood-frame building tests to validate retrofit philosophies proposed by (1) the Federal Emergency Management Agency (FEMA) P-807 guidelines and (2) a performance-based seismic retrofit (PBSR) approach developed within the project. Four different retrofit designs were developed and validated at full-scale, each with specified performance objectives, which were typically not the same. This paper focuses on the retrofit design using cross laminated timber (CLT) rocking panels and presents the experimental results of the full-scale shake table test of a four-story 370 m2 (4000 ft2) soft-story test building with that FEMA P-807 focused retrofit in place. The building was subjected to the 1989 Loma Prieta and 1992 Cape Mendocino ground motions scaled to 5% damped spectral accelerations ranging from 0.2 to 0.9 g.Keywords: cross laminated timber (CLT); performance-based seismic retrofit (PBSR); FEMA P-807; soft-story; wood-frame; shake table testing; seismic retrofit 2ff7e9595c
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