Log In Register

Spray insulating a shipping container

  • Thread starter Thread starter iscrog4food
  • Start date Start date
  • Tagged users Tagged users None

Spray insulating a shipping container

iscrog4food 20 Replies 29,295 Views
Page 1 of 2 · Replies 1–20 of 21
iscrog4food

iscrog4food

Posts
629
Reactions
90
Joined
Aug 23, 2010
Points
28
I have a 40' high cube shipping container that I need to insulate to mitagate some condensation problems I have been having. I have been considering a closed cell foam type insulation but I would really like to hear from someone withe direct experience with this type of situation. I live in a cold weather climate and the container is in an uninsulated garage so it gets pretty hot during the summers. I would like to know if anyone has any reccommendations as to the best type of foam to use and what all is entailed. Any help is appreciated.
 
I have not done exactly what you wan to do, but I have a lot of experience in construction. Spray foaming is not going to fix your problem. Where I am is humid as hell. Right now it is somewhere around 70%, and we can't get away with spray foaming or making houses air tight, or they will drip water on the insides, and mold. Similar situation for you. The best thing to do is to lower the humidity with an A/C unit. Another cheap way to help out would be to have an exhaust(either timed/or hooked to a humidity type timer) that kicks on every once in a while, similar to a greenhouse. You need to treat this like a greenhouse, and you could probably solve your problem much easier. Think about spray foaming a greenhouse. Do you think there would be no condensation then? Absolutely not. Get on some greenhouse websites, and see what you can come up with.
 
You can frame out the inside with 2x2s and use the thick polystyrene 4x8 sheets from home depot,on the floor sandwich them between the existing wood and 3/4 inch plywood on top.You will still need a/c and dehumidification though.Being in the garage will help for sure.
 
There is alot less condensation if you insulate the container space because there is not as much temperature differential on the contact surfaces where the warm moist air hits the skin of the container...your basically building a sealed insulated meat cooler or igloo ice chest cooler..you still need a dehumidifier, but most sealed rooms do no matter what you do unless your a/c is suckin enough humidity out of the space to manage...you need 2 tons of a/c, possibly 3 tons but you might could get away with 2 tons only..mini splits are the way to go

The spray foam you use is a water proof closed cell and you need to get a insulation contractor to come in and do it unless you know what your doin and have the rig it is a pro job..you'll probably need to build out the walls so you can fill the cavities with foam and then cover with green rock, plywood, or panda

Here is Remo doin a little tour of a container setup...


Here is a decent setup
 
I have a 3 ton split and I intend on getting another 3 ton split as well. The UG vid is where I got the idea for the insulation. I was considering the polystyrene but I was worried about moisture building between the container and the insulation. Concerning the rig it seems at they sell kits to do it which include the gun for $600 for 600 board feet ( I'll need 2 kits I beleve). Pros are quoting twice that price to get it done plus the operational security hazard.
There is alot less condensation if you insulate the container space because there is not as much temperature differential on the contact surfaces where the warm moist air hits the skin of the container...your basically building a sealed insulated meat cooler or igloo ice chest cooler..you still need a dehumidifier, but most sealed rooms do no matter what you do unless your a/c is suckin enough humidity out of the space to manage...you need 2 tons of a/c, possibly 3 tons but you might could get away with 2 tons only..mini splits are the way to go

The spray foam you use is a water proof closed cell and you need to get a insulation contractor to come in and do it unless you know what your doin and have the rig it is a pro job..you'll probably need to build out the walls so you can fill the cavities with foam and then cover with green rock, plywood, or panda

Here is Remo doin a little tour of a container setup...


Here is a decent setup
 
I have not done exactly what you wan to do, but I have a lot of experience in construction. Spray foaming is not going to fix your problem. Where I am is humid as hell. Right now it is somewhere around 70%, and we can't get away with spray foaming or making houses air tight, or they will drip water on the insides, and mold. Similar situation for you. The best thing to do is to lower the humidity with an A/C unit. Another cheap way to help out would be to have an exhaust(either timed/or hooked to a humidity type timer) that kicks on every once in a while, similar to a greenhouse. You need to treat this like a greenhouse, and you could probably solve your problem much easier. Think about spray foaming a greenhouse. Do you think there would be no condensation then? Absolutely not. Get on some greenhouse websites, and see what you can come up with.


Where I am it is dry as hell 30% rh most of the year. I have a sealed room with a 3ton split but the condensation is building because when it is cold outside and warm in the container the differential causes moisture to build onthe roof. Also I want to avoid running the split full blast when list are off to save electricity because my garage gets to 100 ish degrees during the summer.
 
You can frame out the inside with 2x2s and use the thick polystyrene 4x8 sheets from home depot,on the floor sandwich them between the existing wood and 3/4 inch plywood on top.You will still need a/c and dehumidification though.Being in the garage will help for sure.

The flor has thick wood and is fairly well insulated. I am more worried about the walls and roof.
 
I've used closed cell spray foam on many projects and it works great, the perm rating is excellent. The one down fall is the it does not do a good job of stopping sound. I would recommend adding some type of sound baffling to stop the transfer of noise.
 
I've used closed cell spray foam on many projects and it works great, the perm rating is excellent. The one down fall is the it does not do a good job of stopping sound. I would recommend adding some type of sound baffling to stop the transfer of noise.

This raises the interesting possibility of stacking multiple coatings to solve different problems. Perhaps a moisture barrier first, followed by insulating foam, and finally a sound deadening formula on top? The last layer could also be a moisture barrier, and could be white to serve as a reflective surface... 'paint', I think they call it.... j/k but seriously, is this making sense to anybody else?
 
This raises the interesting possibility of stacking multiple coatings to solve different problems. Perhaps a moisture barrier first, followed by insulating foam, and finally a sound deadening formula on top? The last layer could also be a moisture barrier, and could be white to serve as a reflective surface... 'paint', I think they call it.... j/k but seriously, is this making sense to anybody else?
Many insulations have a vapor barrier on them. The paper facing is usually a vapor barrier. So when you see it in basements with the paper side down, that's wrong. People should be using unfaced batts for that application. It's cheaper anyway. There really isn't any moisture transfer in situation above though. The differences in temp are causing the condensation due to the fact that the relative humidity is, well relative. Although at 90 degrees it may feel pretty dry, that same air with the same amount of moisture in it cools. At cooler temps the air cannot hold the same amount of water and the cooler surfaces condensate it. With a good insulating barrier, the surface on the hot side will stay close to the hot temp and vice versa.
 
Underground and others here are absolutely correct- when they suggest insulating as a direct response to condensation, they're solving the underlying problem.
 
Many insulations have a vapor barrier on them. The paper facing is usually a vapor barrier. So when you see it in basements with the paper side down, that's wrong. People should be using unfaced batts for that application. It's cheaper anyway. There really isn't any moisture transfer in situation above though. The differences in temp are causing the condensation due to the fact that the relative humidity is, well relative. Although at 90 degrees it may feel pretty dry, that same air with the same amount of moisture in it cools. At cooler temps the air cannot hold the same amount of water and the cooler surfaces condensate it. With a good insulating barrier, the surface on the hot side will stay close to the hot temp and vice versa.
Underground and others here are absolutely correct- when they suggest insulating as a direct response to condensation, they're solving the underlying problem.

So would glueing down sheets of rmax do the same thing if I tape the seams?
 
Rmax and aluminum seal tape is how I do a few of my rooms and it works great ..not sure about gluein them directly to a container wall though
 
I have been reading up on it and it is really hard to find an answer pertaining to this application. Spray foam will cost double what rmax will and I know that will work 100% with the moisture. I am just worried about water building between the rmax and the container wall. I need to make this decision soon.... I'm leaning toward the spray foam..
 
Have you thought about using sheets of extruded polystrene, glue it to the the container. Tape all the joints with the proper tape. Buy a foam gun made to seal around doors and windows. ( kinda like great stuff) however with the metal gun you can use a little or alot. The gun is $40.00 and the cans of spray foam are $10-$12 I pay about $1.00 per board foot of installed closed cell foam. I believe the kits you are looking at will cost at least twice as much. A sheet of extruded poly is $22.00 per sheet or .70 cents per square foot.
 
If ya don't care what it looks like, how about framing the outside with treated wood, weatherproofed OSB, and batts of insulation? It might look a little strange to have a wooden box sitting in your yard, but probably no stranger than a metal container... Metal is just a terrible exterior material to insulate- in my grows I actually frame out smaller rooms inside of a larger uninsulated metal structure and leave at least an inch of space between the walls of my grow and the outside.
 
Have you thought about using sheets of extruded polystrene, glue it to the the container. Tape all the joints with the proper tape. Buy a foam gun made to seal around doors and windows. ( kinda like great stuff) however with the metal gun you can use a little or alot. The gun is $40.00 and the cans of spray foam are $10-$12 I pay about $1.00 per board foot of installed closed cell foam. I believe the kits you are looking at will cost at least twice as much. A sheet of extruded poly is $22.00 per sheet or .70 cents per square foot.
Have you thought about using sheets of extruded polystrene, glue it to the the container. Tape all the joints with the proper tape. Buy a foam gun made to seal around doors and windows. ( kinda like great stuff) however with the metal gun you can use a little or alot. The gun is $40.00 and the cans of spray foam are $10-$12 I pay about $1.00 per board foot of installed closed cell foam. I believe the kits you are looking at will
cost at least twice as much. A sheet of extruded poly is $22.00 per sheet or .70 cents per square foot.

The spray foam kits are also $1 per board foot. Rmax wouldn't save much money and I am concerned with water forming in the gap between the 4x8 sheets and the container wall and moulding. I'm pretty sure I'm just gonna nut up for the spray foam.
 
If ya don't care what it looks like, how about framing the outside with treated wood, weatherproofed OSB, and batts of insulation? It might look a little strange to have a wooden box sitting in your yard, but probably no stranger than a metal container... Metal is just a terrible exterior material to insulate- in my grows I actually frame out smaller rooms inside of a larger uninsulated metal structure and leave at least an inch of space between the walls of my grow and the outside.
I do care what it looks like haha. Also I live in the country where everyone has huge barns and shipping containers and tractor trailers ect.
 
Page 1 of 2 · Replies 1–20 of 21
Back
Top Bottom