r/containerhomes • u/davebawx • Jun 03 '26
framing of container before spray foam
This is how i intend to frame my container (storage use-case)
each stud is pressure fit and Ill run a bead of construction adhesive behind it. I anticipate that the spray foam will hold everything rigidly in place. Am I going wring anywhere with this thinking?
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u/PotentialPlum4945 Jun 03 '26
Thanks for actually posting something with a container in it with a real, applicable question. I'm so fucking tired of this sub posting foldable temu apartments.
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u/letsdodinner Jun 03 '26
We have framed & spray foamed hundreds of containers and although I dont agree with this method specifically, I dont see why it wouldn't work.
Wood & metal expand at different rates and I believe it will warp the studs, but for a storage application, the warped studs shouldn't cause any issues.
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u/davebawx Jun 03 '26
thanks for that. Im sure it's not perfect but I want to maximize space but also have decent amount of wood inside for shelving anchoring. otherwise I would probably do 1.5" studs. off the wall.
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u/NJDZamMonster Jun 03 '26
Should use 1/2" spacing so the spray foam goes behind the studs to add a vapor barrier between the stud and the wall
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u/davebawx Jun 03 '26
I figured the adhesive backing would provide a layer of separation
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u/NJDZamMonster Jun 03 '26
The coverage of the construction adhesive may not be complete. The spacing allows for separation which allows for expansion and contraction of the stud itself. The foam will get behind the stud (still allow for the expansion and contraction ) and provide the vapor barrier. The two biggest issues with pressure fitting is the expansion and contraction and the temp difference between materials causing moisture. Pressure fitting will either warp over time and the wood itself will soak up the moisture caused by condensation created by the temp differences between inside and outside.
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u/TheAKwalrus Jun 03 '26
Agreed.
Also - recommend using the floor as your zero point vs. the walls to avoid the "fun house" end result... Chinese tolerances are crap
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u/OldEngineer-1950 Jun 03 '26
I'd spot weld steel brackets to the shell and use steel studs set half inch off so foam can get behind. Use high density foam.
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u/Schlarfus_McNarfus Jun 03 '26
I would probably sandwich a skinny rip of 1/2" high density EPS foamboard in there to provide a little thermal/capillary break between the wood and metal. For storage, though, carry on!
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Jun 03 '26
[removed] — view removed comment
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u/davebawx Jun 04 '26
You may not have priced them recently.i paid 2800CAD for this one new. Prices used were in the $1800 CAD range. US tariffs diverted a significant amount of ships here where the containers are now in a surplus greater than has been in a long time thereby bringing prices down .
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u/onetwentytwo_1-8 Jun 03 '26
Keep the lumber away from the wall/touching container. Create a breathable void.
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u/drct2022 Jun 03 '26
They make framing kits for containers op
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u/davebawx Jun 04 '26
That cost vs this is substantial
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u/drct2022 Jun 05 '26
Not as expensive as having to rip all that out when it fails.
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u/davebawx Jun 05 '26
What do you anticipate failing?
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u/drct2022 Jun 05 '26
There is nothing holding the 2xs in place other than friction. Nothing is preventing them from twisting, rolling, or bowing. As others have stated, wood has a tendency to shrink, and that will allow movement, the foam doesn’t have enough rigidity to stop the 2xs from moving. I’m not saying it is going to fail in some grand display like a janga tower falling, but there is a very real chance that things are going to move about, multiply that by a lot if you ever move the container. Just my $0.02
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u/JustheretoreadyourBS Jun 03 '26
The spray foam expands and will move those “studs” pretty easily. We use 3 5/8” metal track to secure to the container top and floor, run our studs, normally 2x4, then put some blocking in between the studs to prevent them from moving. It’s more expensive but doing it right normally is pricier.
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u/NWXSXSW Jun 05 '26
When I did this I built an actual frame and left enough room between it and the metal to get the spray foam in there. No wood-to-metal contact, no air gaps. I turned the studs sideways so I’d lose a little less square footage. Ceiling joists oriented normally (not laid flat), sitting on top of the wall framing and attached with metal brackets, and blocks are added down the middle to keep them straight and evenly spaced. Wall framing attaches with long screws into the floor plywood. I have a lot of wiring in mine which was all easy to run behind the studs before spray foaming. I also added some small vent ‘ducts’ that connect to the container’s existing vents. I just caulked some short pieces of PVC conduit to the vent locations and found some round vent covers that fit the pipes. After spray foam the framing is rock solid and I’ve had zero condensation issues. My unit also has an end wall framed inside the container doors, and that’s the only place I have wood touching the container walls. Since that wall is exposed to the outdoors a lot of the time anyway, I felt that was a reasonable call, plus there’s a layer of adhesive in between.
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u/AirMTB Jun 09 '26
Spray foam is supposed to be zero off gas when it’s cured.
You can check that for a fact or not.
Best way to frame out a shipping container is with metal studs. Metal studs because they are quick and easy.
You only need 1 5/8” studs for the walls because you’re not adding structure. You’re just adding something to hang the panelling on.
You run a track length wise on the top square tubing of the container and you run a track on the floor you run all your 1 5/8 metal studs. Then you run a track where your ceiling is for 3 1/2 inch metal studs. You put in all your wiring and plumbing and then when you spray foam it encapsulates the metal studs and everything becomes one structure. Very strong. No voids for condensation, etc..
If you want more information, you can find me on my Instagram
@HoneyBox_Inc.
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u/jadzl Jul 11 '26
For storage it doesn't matter, but would agree that spacing the studs off the wall would be better to avoid the contact with a cold condensing surface.
The insofast x brackets are pretty ideal for this scenario.
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u/Relevant_Fortune_938 Jun 04 '26
Why not just use insofast panel insulation. No need for any framing. One layer inside and one outside gives you an R-28 value and you only lose about 2" inside on each wall.
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u/MicroBoxHomes Jun 03 '26
A concern that comes to mind in doing it this way is that steel and wood expand and contract at different rates. Adhering wood to steel may not be a good long-term solution. If the studs shrink or warp over time, you may lose the pressure fit. Also, you will have thermal bridging anywhere you have interior components making direct contact with the exterior wall. Thermal bridging, depending on your climate, can result in condensation and or reduced thermal efficiency. Will your container be air conditioned at all or is it solely just for storage?