I don't know why anyone would be spraying foam on the outside of a barn but foam hits a surface as a liquid and then immediately turns into a foam. Very little of the liquid is likely to adhere to the bicycle so the foam would expand from the wall surface outward and begin to envelop the bicycle and it would become firmly adhered to the wall if the foam is thick enough. But that much foam requires multiple passes and would be unlikely to be used for insulation purposes. Open celled foam often has a soft matte surface and closed cell foam has a harder surface with a slight sheen. Foam insulations stick to everything and are very difficult to remove. There are many videos of foam installations on YouTube. Here is a link that might be useful: foam video

I've found that rooms over garages are very hard to condition. there are a couple of ways to address this, walls shared with attic space are called kneewalls. on one side is living space (conditioned) on the other side attic space (extreme heat/cold). Southface has great info, check page 5 for visual of air sealing these walls. http://www.southface.org/default-interior/Documents/airsealingkeypoints.pdf with these attic rooms surrounded on 6 sides by extreme attic temps there are two ways to address them. one is pictured in link. convnetional insulation in stud bays, foam sheathing, caulked nailed & taped in place from top plate to bottom plate of kneewall. the detail on link also shows how to seal for air movement under floors of these rooms by using foam board, and placing it between floor joists & sealing air tight. I personally like to cut the foam board to fit tightly & air seal with caulk. I see people using great stuff..but am not a fan of the stuff myself. too much expansion to get a good seal, and over time, it shrinks. this is a process that is time consuming & detail oriented. easiest in new construction prior to any insulation being added to attic floor. more cost effective than spray foaming the walls and between floor area. but labor intensive. so its a easy fast process (spray foam) or a longer lower cost higher labor install with foam board. the benefit of creating an unvented semi conditioned attic space works great in my hot humid climate where in the summer attic temps reach 130+ degrees in attics. as we often put our ducts in the attic, the foam creates a less extreme temp for less heat gain. install of foam is crucial. temp mix has to be correct chemical mix has to be correct, temp of area sprayed is a factor. foam has to meet code requirements for your area. if code says R-30 in attic, enough inches of foam to reach that R-value has to be installed. seal has to be complete in an unvented attic. roof connection to attic floor has to be sealed. install should be level, no belly in or out between rafters. faces of rafters should be covered. none of that average fill stuff which means the spray can be less in some areas & more in others so that it 'averages' out to xx inches. low spots & voids will cause problems. testing for leakage, marking leakage sites with spray paint and having foam company spray to seal is the way I do my unvented attics. this all has to be established, in writing prior to any work being done. shop companies carefully. avoid 'average' fills, Kvalues Qvalues. R-values that is what code looks for. there is No exception for spray foam. I'm with Manhatten all the way on spray foam in walls. long payback when a better option is to put foam sheathing on exterior of walls & pay close attention to air sealing details. search southface site for air sealing pdfs..great stuff there! I've never recommended spray foam in walls after running the numbers for my climate & seeing 25+ year paybacks. and I've done these numbers lots of times, not just for one house. (btw hey Manhatten..long time no see) if you chose to use these details of air sealing for the tradeoff for this better insulation is SMALLER hvac system. it only makes sense people if you weight the benefits of upgrades against each other. get a load calc for the house including all types of insulation, window info, air tightness tight not leaky or average & the size needed lessens. bigger is not better, it is just lack of correct education in the trades & misinformatin to the homeowner to sell them more equipment than needed. you don't size the system for the 10 days a year of 50 people in the house & then pay for that the other 355 days. two stage units, variable speed air handlers are great things that vary with the needs of the house as they change. these are good investments. if you are truly interested in making your house efficient, hire an energy rater. specific to you information with inspections, testing & verification. unbiased working for you. resnet.us is a good place to start. new construction, existing homes we do it all. best of uck.

"madpebs87 "plus then you might actually have to seal some of the holes in the ceilings." Wouldn't you do this anyway? You foam the roof deck/rafters, do nothing to the ceiling for insulation, why would you not seal all the plumbing/lighting etc holes that go up into attic? Great thread (bookmarked) giving me lots of info when i build in 3 years in coastal ga." been out of town so just getting to answer this. when the attic is vented, you absolutely want to seal all openings between living & attic space. when the attic is unvented & foam sealed, then you want air exchange between living & attic space. you can get this exchange from not sealing the openings that trades make & never seal, or seal it up tight and dedicate an exchange air pathway. problem is...seldom does anyone seal these openings, so adding a dedicated pathway is redundant. people think they built tighter than they actually did in my experience. but it is all just a guess until you blower door test to see what leakage actually exists. build tight, ventilate right, and TEST to find out what performance actually is. OP, I have to defer to folks in climates with basements, as we have too high of a water table in La. for basements. I have no hands on experience with basements, best of luck.

Considering insulative sheathing has made it's way into prescriptive minimums, I think it's more of a requirement than allowment. The "+" value in wood framed wall R value below denotes insulative sheathing prescriptions. Typical framing results in walls where 20-30% of a wall's total area, has no cavity insulation, which drags down the entire wall area's performance. For owners or designers after the most "R per inch" insulative sheathing is more effective than cavity insulation as it better encapsulates framing and structural components. This potentially increases airtightness, reduces thermal bridging and keeps structural components warmer, reducing chances of condensation and rot. The last feature may be why codes are beginning to adopt insulative sheathing as best (minimum) practice and calculating the minimum insulative sheathing is important for wood framed walls in cold climates. In the warmer climate zones of 2 and 3, a 2x4 wall with 1/2" of insulative sheathing outperforms a 2x6 wall and is thinner. As for Open Cell foam in roofs, I agree it's a relatively new practice posing risk and the same is true for Closed Cell. That's why many experts recommend insulative sheathing on top of roof structural sheathing and why the traditional unconditioned attic is appealing, as long as it has an airtight ceiling plane (tough part) and a thick layer of loose fill insulation. Roof leaks are typically more common and damaging than condensation and I think closed cell complicates discovery and repair more than open cell, but in cold climates I would prefer closed cell. Martin's article sounding the alarm about modeling studies is useful, but I think the onus mainly falls on field results and the vast majority of open cell roof decks seem to be working fine, other than the unfortunate reality that most spray foam installations are below code minimum performance. A good friend of mine is building in TN and we just went through all this. He was able to get good pricing for a flash coat of closed cell against the bottom of the roof deck, followed by filling the rest of the rafter cavities with open cell.