Insulating My Pole Barn - need help

[srs]

Steve, here is a link to the Morton Building website, some info here as to how they insulate their buildings.


Our Features - Energy Performer® Package by Morton Buildings, Inc.

 

[BuilderML]

Hi Steve,
The moisture in the air you are worried about comes from warm air. A vapor barrier needs to be installed on the warm side of the wall and or ceiling to stop the vapor from getting into the wall cavity. Tyvek is NOT a vapor barrier. Use a 6 mil poly as a vapor barrier and make sure you seal it to the floor with a draft stop caulking and tape all your seams with a builders tape. Any holes in plastic will allow moisture to go thru.
Steve i am sorry to say but i think your looking at this the wrong way. I am not trying to be rude by saying this but if your not going to do it right do not do it at all as it will come back and bite you in the end. When building something it will NOT be cheap only thing i can say is that your budget was figured wrong so do not try to cut corners or buy cheap materials to "just get it done".You will only waste your money. Styrofoam should be kept to make coffee cups and thats about it. Now with your project i would hold off until you gets the funds to do it right.
Here is what i would do:
1) Use a closed cell spray foam on walls and ceiling min. of 2.5 inches will allow you not to worry about the vapor barrier as the thermal break happens within the foam itself you will have no condensation issues.
2) You can spray right onto your metal panels but that will cause problems if for some reason you would need to fix or replace a panel due to damage in the future. If your not worried just spray right over.
3)Cover the foam with what meets your local building codes as it is very flameable. You may be able to just spray a fire resistant paint over the foam if it is allowed in your area.
Yes it is expensive but like i said save yourself problems in the future.

Good luck Steve
Like i said i am not trying to be rude just be wise when spending your money.
Talk to a reputable local contractor or building official and get his input on your project for your area

 

[Jnasystems]

I am in a similar situation. I have a 32x42 metal pole barn and found a guy that sold me 400 sheets of 4x8 2.5" thick styrofoam insulation. The plan was to install it in 2 layers to give me 5" everywhere. There was some fiberglass insulation already there - about 2" thick. I figured that I would get to about R30 over all. So with that said, what is wrong with styrofoam? I do plan to put up some plastic after the insulation is all in, but I didn't have plans to cover that at this point - maybe one day. Am I creating a fire hazard? Will there be damage done to the building that I haven't thought of? Does it need to have a fire barrier right away? I don't have much in it at this point since I got the foam for $300, but if there is excessive risk, I can still change direction.

Thanks

 

[BuilderML]

HI Jnasystems
One of the big concerns with using foam is how toxic the fumes will be if fire is ever present let alone the fact how fast it will spread. The fumes will take you out in seconds. Leaving plastic exposed will do the same thing if a fire is ever present. They do have a plastic made for applying over unfaced batt insulation that is fire retardant and is used in applications when no wall covering will be used. Sorry i can't comment on 5" of styrofoam it is not a practice i have ever used and i don't want to give you the wrong info.

 

[KennyG]

Definitely you need to get a good fire barrier as soon as you can, but that goes with any foam. My biggest problem with styrofoam is that it's not very consistent (which is why it's cheaper) and it's hard to cut and get a clean edge which makes it hard to get a good seal between the sheets. Work with some polyiso (which has almost twice the R value) and you'll see the difference. That said, you've got it and you got a great price so go for it, but plan on putting a sheet plastic vapor barrier on the inside and then cover it with a fire barrier. You can't leave the plastic or foam exposed permanently. That's just too dangerous.

We've talked about the inside finishing before and drywall, OSB, and metal liner panel all have their advantages. If you're not wired or adequately wired already, think about doing all your wiring in conduit on the wall surface. It will make fitting the foam panels a lot easier and give you a better seal. I learned this the hard way.

 

[yanmars]

I will start by saying this may not be the correct way but this is how I did mine. I have a 40x81 Cleary building. It has a 1 foot ventilated overhang all the way around and at the peak a continuous cap to let the warm air out.
I got about 3500 square foot of used rigid foam roof sheeting, 3 inches thick for $300. I cut the 4x8 sheets to fit between the ceilings nailers 2 foot on center. I used screws in the nailers to hold them up but I cut them so close to size that they nearly held themselves in place.
I got new offals of Pink Dow rigid foam in 1/2 thick. On the side walls I attached them the same way but in two pieces for 1 inch thick. I staggered the seams. I did my 5 overhead doors the same way. The side wall insulation was under $150. The screws were fairly expensive but overall I think I had about $600 total in the project.
I did this because on a few days it would rain inside. Condensation formed on the bottom of the cold roof and then would rain down. Now maybe it just rains down on the rigid foam and is making a mess in there, the hope was there was enough insulation to avoid the condensation. The building certainly is more uniform in temperature and certainly cooler in the summer. I have a dirt floor at this point and no heat or electric in it.
Certainly not saying it is right, only how I did it. If a problem it would not be hard to remove, take the screws out.

 

[zmansmac]

When I moved to my present house in SE Michigan 11 years ago the 24 x 32 x 12H pole barn was going to be my new woodworking shop, so it had to be insulated so I could use it year round. I happened to get a good deal on some "seconds" plywood to keep costs down. I nailed 3/8 thick to the ceiling and screwed 5/8 thick to the sides after putting in 6 inch fiberglass insulation on the sides. I blew in about 12 inches of cellulose in the ceiling. But I did make an access hatch with 4 inches of rigid foam. In the two front sliding doors I glued 2 inch rigid foam between the 2 x 4s. And then I mounted sections of the garage seal stripping on the inside by the sides of each door and along the top (this also helps keep even small critters out as I have never even had a mouse inside). Drywall could be used for the ceiling and sides but the plywood worked better for me since I have all kinds of bins, parts cabinets and wood racks mounted to them. The insulation was all purchased at the same time I added some fiberglass and cellulose to the main house and so was able to claim it as an energy credit. I have a small ceiling mounted Reznor natural gas heater that doesn't have to run to often to keep it at 62-64 degrees in the winter. The other plus is on a 90 degree summer day it stays in the low 70s as long as I keep all the doors closed. I did not add a vapor barrier and have not had a problem with humidity. And after all the plywood was up I sprayed the sides and ceiling with white paint. My ten double 4 foot florescent fixtures give plenty of light with the white paint.