Insulation of pole barn

[86Vette]

Hi all! I am going to have 4" of open cell foam sprayed on the walls and under side of the roof of my pole barn a few weeks. Wish I could do closed cell but can't afford the additional cost. In any event, my question is this - I plan to hang metal for a ceiling later on. Should I somehow insulate the top of the ceiling too...or is the spray foam on the underside of the roof sufficient? My contractor friend told me the ceiling probably could not handle the weight of loose cellulose insulation. The building will be heated and cooled so I want to do whatever I can to lighten the load on the equipment and make it run as little as possible. Any thoughts would be appreciated.

 

[readhead]

Is the foam being sprayed directly on the metal sheeting? Have you looked into the issues of foam sprayed on metal? I would highly recommend you do some research.

 

[86Vette]

I actually just saw a post on this subject indicating it can be problematic to spray directly on the metal. What measures can I take to ensure the foam does not separate from the metal over time?

 

[readhead]

It won't separate. It traps moisture and the metal siding and framing will begin to rust. I am a metal building contractor and I have seen this kind of damage. It has taken several years since spray foam became popular for this kind of damage to show up but now I am seeing it quite often. I think spray foam is a great product but not for this application.

 

[86Vette]

I've googled the issue and and as with most things, you find about as many people saying it's a problem as you find say it's a myth. I found this commentary on the issue from a spray foam contractor who is also from Iowa (but I am not using) -- https://iowasprayfoam.com/moisture-myths-and-spray-foam/

Bottom line, I've already paid half the money down and I'm moving forward with it. I guess I'll just have to hope for the best.

 

[readhead]

It's a spray foam company so of course they say that. Another problem is replacing or repairing damage. The sheet is glued to the building and can be almost impossible to remove. We will not do repair or remodel work on spray foamed buildings.

 

[Joe_K]

It's a spray foam company so of course they say that. Another problem is replacing or repairing damage. The sheet is glued to the building and can be almost impossible to remove. We will not do repair or remodel work on spray foamed buildings.

That’s why I had cellulose blown in the ceiling and I’m doing R23 Rockwool batts in the walls.

 

[bullnerd]

Im kind of curious about this also.

Getting back to OPs original question.

If you foam the underside of the roof, then install metal ceiling panels, then heat the space. If you have a vented eave or ridge, will moisture condense on the ceiling?

I guess the building will have to be totally sealed?

I know what I'm trying to say...but I cant type it! lol!

I used fiberglass blankets and am blowing in the ceiling.

 

[LifeLongWNYer]

I started a similar thread a few days ago, but saw this on my way to check mine.

One suggestion I've just received, is to put a sheet of Tyvec building wrap on the metal siding prior to spraying the foam.....is this "news or noise"?



.

 

[readhead]

I've seen mixed results with tyvec. In smaller sections it seems to work but in larger sections I have seen some problems with the tyvec sagging. In a typical house it is usually being applied to OSB or plywood in stud bays. Blanket insulation is still the best bang for your buck. I find that a lot of people nix the insulation to save money thinking they will do it later. They find out that it is usually harder and more expensive to do it later.

 

[whitemamba]

I was thinking about spray on foam for inside of my pole building, I already have building skinned what is my option to insulate?

 

[stm317]

I started a similar thread a few days ago, but saw this on my way to check mine.

One suggestion I've just received, is to put a sheet of Tyvec building wrap on the metal siding prior to spraying the foam.....is this "news or noise"?



.

If the building isn't up yet, it's much easier to wrap the framing with Tyvek before installing the siding than it is to try and do it after the fact. Technically, you want to have a moisture barrier (Tyvek, etc) between the metal and insulation anyway, no matter what kind of insulation you're using. Having it there with spray foam just prevents it from seeping out of every seam, and allows the metal to be removed much more easily if needed.

I've heard that some foam installers won't spray onto anything like Tyvek or double bubble on the underside of a roof. They express concern that the weight of the foam might cause sagging/failure. You, your builder, and your insulation guy need to all be on the same page

 

[jimp]

I was thinking about spray on foam for inside of my pole building, I already have building skinned what is my option to insulate?

Not to hi-jack the thread, but put 2X4 wall purlins on the inside and skin it with panel liner, fill the void with insulation. Results in nice clean interior and efficient.