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Insulating Underside of Shipping Container House w Dwgs

xplorer8's picture

Insulation Question

I have been trying to come up with method for insulating the underside of a shipping container house. Some of the constraints and design parameters below;

- containers (3x 40ft) will sit 3ft off the ground to create a space for accessing plumbing and to install insulation

- based on recent research, insulating between the metal C-channel beams won't help much due to the high thermal conductivity of the metal (at the same time I don't want to install any insulation above the wood floor to perserve as much interior height as possible), the research paper is by Roque and Santos found here

- currently thinking, just a thin spray foam layer along the underside of the wood floor between the beams to provide my vapour barrier, then glue on/attach somehow 6 inch EPS panels to the underside of the metal floor C-channel beams, skirting around the house to prevent unwanted pests in the crawl space

Other solutions to keeping the floors warm in the cool windy winters of Southern Ontario?

I have attached a preliminary set of drawings I produced myself.

As an aside, you can almost comment on having the ducted indoor minisplit unit in the attic, I think I might need to bring it into the house and just lower, say the hallway, ceiling to accomodate it??

Also if there is anything else you want to comment on let me know I would be glad to discuss, I am only at the design stage at this point so all changes are welcome and potentially helpful.


Container Discussion

I imagine the idea of a shipping container might be a bit odd for some and I can also see the benefits of a traditional superinsulated house with double seperated wall designs but here are some of my reasons for the container choice;

- shortened build time, the containers come with the door and window openings already framed in metal, I can simultaneously work on the roof and interior walls/finishes, also no exterior finishes are required (though I might add wood panels to reduce industrial look not sure yet)

- strength, these boxes are made to pitch and roll on the ocean in hurricanes with 50,000 lbs of goods inside, we have tons of 80-100ft trees on our yard and will be near Lake Huron meaning occaissional wind storms so chances of one falling is quite likely, a 3x3 in steel truss is going to have a much better chance of holding up that tree than a 2x6 truss, obviously cutting out large sections of the containers for the interior rooms will decrease its strength but adequate new supporting will be provided to counteract this and any sag potential

-vapour barrier, once the containres are welded together the opened interior is easily accessible to coat the entire interior (except floor) with a coat or two of spray foam against the metal container, providing a solid start to the R-value of the walls and providing my vapour barrier

- reduced foundation requirements, the containers can sit on just their corners but I would likely do mid-span as well, for our site we just need 12" dia concrete piers to a dense sand layer, the utility room will be a typical basement but given its size (8x10ft) it won't require much work compared to a traditional 1000 sqft basement

Best regards,


Build walls to the ground and (post #215662, reply #1 of 1)

Build walls to the ground and insulate them and the ground. 

Florida Licensed Building Contractor, 50 years experience in commercial remodeling, new homes, home remodeling and repairs and all types building maintenance.