Another insulation question

[wantacoe]

I am finally ready to insulate my pole building. I have searched the internet and am more confused then ever. One article says to never use fiberglass insulation in a steel building but I see a bunch of places selling fiberglass and advertising it as for a metal building. This is for a completed building so the stuff that goes on before the outside steel is not an option. Also, this is an old building and nothing is near square so the 3.5" foam board I have is out. I need something that is easy to cut to fit. Any ideas? Thanks

 

[FredWanaker]

closed cell spray foam contractor. Won't be any room for the moisture in the air to get behind, condense and rust / mold

 

[wantacoe]

I forgot to mention that I read a couple articles that said spray foam should not be used in a steel building.

 

[fuggle]

I wouldn't worry about spraying your metal building. I didn't. I sprayed mine. You are not the first to mention about "a couple articles" saying not to foam metal. Not sure where that comes from. There was a discussion in another thread about it. My foam contractor sprays metal buildings all the time. And I got the idea from a guy who sells metal buildings. There aren't any other good insulation options. I looked for a long time and didn't like what I found.

 

[Firebrick43]

I have personally seen two metal building have major structural/steel damage due to spray foam applied directly to the metal. One had to have the whole corner of the building replaced, including metal, girts, and post. The other had roof damage(rust) and some purlins. All the steel R panel manufactures warrantees are void if spray foam is applied directly. If you do want to use spray foam provide something like tyvek to spray on.

As far as fiberglass, while not as good per inch as other forms of insulation I fail to see any issue? I would bet that someone telling not to use fiberglass is hawking something else like spray foam and not disclosing that info.

The best solution I IMHO is to put 1.5" xps or eps foam between the girts(2x4 on the outside of the post). This easiest to do while construction is going on. you can buy xps prescored. Place you first girt, and then put on your 18 or 24" of foam depending on girt spacing. Set your next girt on top and continue. Its not terrible if the shell is already up as you can rip the foam to width and slide it into position. but you will miss a little spot on the back side of the post.

Then hang a blanket of fiberglass that is the width of the bay(available special order or at insulation jobbers)

 

[duneslider]

I think you should go with Havlock insulation. It solves all your problems, is environmentally friendly, works great, absorbs harmful chemicals naturally to improve air quality, manages moisture, absorbs sound, cheaper than spray foam. I don't see any disadvantages to the Havlock.

Anyway, the Havlock is great stuff but I would probably just go with the fiberglass stuff.

 

[racecougar]

Right. Why aren't we supposed to use fiberglass exactly? I'd be interested to see the article.

I did fiberglass batts in my walls and blown fiberglass in the ceiling. Three years later, and I'm still completely pleased with the results.

 

[Bert_]

Fiberglass is the most common thing out there. It is a fine insulator, but you have to get the building air sealed first. Fiberglass does not stop air movement.

 

[meathooker]

Did closed cell on mine. Love it. 2” walls and 3” ceiling.

 

[kj_mustang]

I have personally seen two metal building have major structural/steel damage due to spray foam applied directly to the metal. One had to have the whole corner of the building replaced, including metal, girts, and post. The other had roof damage(rust) and some purlins. All the steel R panel manufactures warrantees are void if spray foam is applied directly. If you do want to use spray foam provide something like tyvek to spray on.

I have used two different metal suppliers for buildings, Central States and Fabral. Just read their warranty information on both and neither state anything about voiding if spray foam is used. They have the same voidable clauses as I am sure most all the manufacturers do. 2" closed cell spray foam applied directly to all the Fabral panels on my building almost 8 years ago. Zero issues.

 

[Firebrick43]

I have used two different metal suppliers for buildings, Central States and Fabral. Just read their warranty information on both and neither state anything about voiding if spray foam is used. They have the same voidable clauses as I am sure most all the manufacturers do. 2" closed cell spray foam applied directly to all the Fabral panels on my building almost 8 years ago. Zero issues.

Central States warranty

Line 6 of the "This warranty DOES NOT APPLY in the event of" sub section.

"• Presence of damp insulation or other corrosive materials in contact with or close proximity to the panel."



Fabral Warranty

"4. To perforation of panels caused by (a) corrosive fumes or condensate of harmful substances generated or released inside the building, or (b) damp insulation or other materials in contact with or close to the roofing or siding panels."



R panels ridges are there not only to provide stiffness but also to provide ventilation behind the panel when oriented vertically. Also in standard pole construction fiberglass never touches the metal. Even if you install EPS or XPS between purlins there is a drainage plane and ventilation still there.

Spray foam if there is wind driven water or a leak under an exposed fastener(and there will be without a doubt) that water is held there. As it freezes and thaws it burst the cell wall of the foam and it absorbs more and more water, holding it against the metal never drying out. Ask anyone that has been around boats for any time and they will tell you about saturated floatation spray foam adding 100's of pounds to a boat.

As for the 8 years, sounds about right. My coworker is sort of a nut for radiant heat and we talked about building construction quite often and he was an ardent supporter of spray foam just like you. We had several debates about it and several years (12 yr old building) later he sheepishly came and told me about the whole corner being damaged requiring metal, wood, and post replacement. Should we blame the spray foam??? Definitely its a water intrusion issue caused by leaks. Problem is there is not such thing as a long term leak free exposed fastener building. Every pole building I have been in with any age has cracked washers and seeps here and there. They are inconsequential for the most part as there is ventilation to dry it out quickly but its still there.

 

[wantacoe]

I was thinking that if I used foam I could first line the building with plastic, that way the foam would not be in the raised portions of the panels so it would have the proper ventilation. Thoughts?

 

[Firebrick43]

They don't recommend plastic as it doesn't bite into it, they recommend synthetic roofing felt or tyvek. I would probably go with the synthetic roofing felt personally.

Even better is to fill the cavities between the girts with xps foam (cheaper than spray foam and still pretty easy) and then spray the the xps/girts.

 

[fuggle]

Central States warranty

Line 6 of the "This warranty DOES NOT APPLY in the event of" sub section.

"• Presence of damp insulation or other corrosive materials in contact with or close proximity to the panel."



Fabral Warranty

"4. To perforation of panels caused by (a) corrosive fumes or condensate of harmful substances generated or released inside the building, or (b) damp insulation or other materials in contact with or close to the roofing or siding panels."

Neither of these statements apply to spray closed cell foam. It is neither corrosive nor is it wet.