I went crazy on insulation here in zone 6 with our new home build last year. Zip-R12 sheathing over 2x4 studs with 3" of closed cell between studs for R-30 walls on a single story home. 2" of closed cell spray on top of the ceiling drywall and 14" of blown fiberglass on top for R-60. Air tight, watertight and comfy in winter throughout with low energy bills. Some people say R-values of closed cell foam degrade in really cold temps but that just an inch or so the outer wall side while the other more interior foam inches retain its R-value because it isn't directly in contact with the outside sheathing and the really cold outside air temp. Insulation temps rise as it gets closer to heat and visa versa. Think people...
If memory serves me correctly, one of the biggest reasons you guys had so many problems with moisture in the walls was simply because of the long screws sticking in from the exterior that only had like 1/4-1/2in of foam around them that turned into little snowballs when winter hit. Had those been shorter screws, chopped off, had a thicker foam layer over them or used a smart vapor barrier you probably wouldn't have had any trouble at all. As much as it sucked though, that was definitely a great learning experience for me watching that fiasco. So thank you for that. I think I'm gonna go the way RRBuildings did their recent HQ build, with WRB plywood sheathing, mineral wool panels between the exterior purlins, 5.5in of mineral wool batts, and a smart vapor barrier on the inside. Seems, to me anyway, like a pretty solid and easy insulation package that also can't burn well.
That was just one of the issues. Another was the contractor not evenly covering the walls. There were places where he didn't even get a full 1" of coverage. Definitely like Kyle's approach as an alternative. Just make sure you seal up all your penetrations.
@@MrPostFrame Oh definitely. I'm hoping I can afford to build it like I would imagine Matt Risinger and Kyle would build a barndominium together: Monopoly framed (overhangs added after the building is weather-tight), full Zip from concrete footing to peak, every penetration get's it's own individual hole that is properly sealed, no roof penetrations (unless it's for solar connections or local code won't let me do a sanitary vent in the eaves), and route utilities in under the concrete floor rather than through the walls. That's not gonna be cheap.... One other issue that I tend to see a lot with typical spray foam insulation is that I often don't see much attention spent insulating the gaps between the exterior girts an the posts, especially at the four corners, which seams like a great way to leave a hole in the air/water-control that might take a decade or more to come back to haunt the owner. Also seems like one of the easiest and cheapest aspects to address, which seems extra weird to me.
Our spray foam contractor pays extra attention to make sure everything is filled in. There’s a lot of ways to build- money almost always dictates the options. We do our best to show a good combination of budget friendly + practices that are worth the spend when you’re working with a limited budget.
@@MrPostFrame As a good contractor should, and should be celebrated and promoted for it. I appreciate all that you guys do. I'm pretty sure at least 65% of the reason I'm so set on building our retirement compound using post-frame is because of watching your videos. Thank you. 😀
If you add the time expense with your insulation costs the benefit of spraying vs. the other option…. It makes more sense to go with spray. Going up and down a ladder using 8’ rolls as a DIY is next to impossible, so you’d need a lift= more money and time for a helper… spray foam… Materials and insulation are 1 expense… it’s probably not that much more after you consider everything that you need to do
Question. There is a build your own RU-vid channel that claims cc spray foam is flammable and shrinks up to 10 % and advises others not to use. Is any of this factual?
There are all different types of spray foam. Not sure what they are using so would need to see the video. I've put a torch directly on the spray foam for 5 minutes. It does char, but does not burn (flammable).
From what I've seen, most shrinkage issues come down to improper installation. Either the mix is off, there's a contamination in the mix, or the installer tried to spray lifts too thick to save time and the foam ends up not setting up correctly. All comes down to spending the time and money to find a quality installer that will take the time to do it right the first time rather than finding the lowest quote. As for flame resistance, most spray foams seem to include flame retardants these days, but some municipalities may require an additional Ignition Barrier be sprayed over the top of the completed foam install. I think the new IRC 2021 may be including that as well, so even if your municipality doesn't require it, it may not be a terrible idea to build to the next higher standard than required.
We are sharing a weekly video that’s a build series right now actually. Here’s the link to the playlist. Don’t hesitate to check out our channel to see what other videos are out! ru-vid.com/group/PL3QM32YjSVn3R9lYxAoEUh3M_tufjYEzj&si=HG7qCV62tBQig356
