I am currently in the midst of converting a pole building with steel exterior to a workshop that I can use year around. The building is actually very similar to a Morton styled building for those of you familiar with that particular brand.
My question is the application of closed cell sray foam. Or would an open cell be just a benefical? I would appreciate any and all comments as I’m new at this and need some expert advise.
My goal is to heat the building which is 24 ft deep and 48 foot long. Roof is a 4/12 pitch. The Iowa temps do dip down there in January and I’d like to be able to heat the work space with minimal costs.
Thank You
Replies
Greetings FWJ,
This post, in response to your question, will bump the thread through the 'recent discussion' listing again which will increase it's viewing.
Perhaps it will catch someone's attention that can help you with advice.
Cheers
Most Morton building have a vinyl covered fibeglass insulation under the steel panels. Even a lot of wood frame pole barns use the same stuff as insulation.
Having worked on a lot of commercial steel frame and sided buildings, I am not a real fan of that type of insulation. It works but not very well IMHO.
If that is what you have, I don't think spraying foam over the existing insulation would work very well. I have seen that vinyl coating stretch, sag, and split open over the years occupancy.
Now if you have bare steel showing from inside it may be the way to go. I'm not foam informed, but there are several people her that are. They'll be along at some point to give you some good suggestions.
Give a little more detail of the construction/insulation if you can.
Dave
Dave:
Thank you for your reply. I've actually changed my plans on the use of foam insulation due to the budget and the expense of the foam.
The building was actually bare on the inside and I've gone ahead and installed 2 x 6 studs around the walls on 2 ft centers to accept the fiberglass insulation and paneling / sheet rock.
I think I can assomplish the same R factor as with the foam.
Again, I thank you for your reply. I'm very much a novice at the carpentry and all of the various construction methods and or best practices.
Frank
If there is moisture generated in the building, make sure you install a good vapor barrier and seal all gaps and openings. Particularly in the roof. If there will always be lots of exhaust air, this may not be an issue.
I've peeled back fiberglass insulation w/ a vapor barrier on it in a ceiling application to find the entire underside of the metal roofing covered w/ frozen droplets of water ... which isn't an issue until they thaw ... then you have major problems.
May not be an issue, but if it is, it would be good to think about it now rather than be surprised later on. Moisture will ruin your insulation and could also wreck your structure.
Mark Williams
Mr Energy / Dick Russel:
Thank you both for your response. I plan on useing the celulite insualtion for the ceiling which I plan on blowing in as soon as I get the sheet rock installed. The roof is wood with asphalt shingles and I can't detech any leakage from the rain or snow thus far. Shingles were replaced two years ago.
I do have one bay of the garage that I want to install a 4 post auto lift in and that will require complete access to the upper area. That particular bay area will be same as a vauled ceiling and I had planned on installing sheets of the foam insulation up agains the plywood roof sheeting. Was planning on installing a thickness of 3 inches.
Do you forsee any problems with the foam sheet installation as a means of insulation that area? I appreciate any any and all information as I don't want to have problems with moisture in the future.
Thank you both for your valued input.
Maybe hold back the insulation from the plywood/deck itself ... leave your vent space above it. Is your roof peak vented? If not, the vent space may provide little benefit. Do your eaves have vents?
It may not be an issue if there isn't a lot of moisture generated inside (e.g. frequently pulling in a car w/ snow/ice on it and letting it sit there) and/or the overhead doors are frequently opened. ... but then you don't know how it might be used in the future ... hence part of the reasons for codes being blind to what you intend to use it for ... now. Maybe chat w/ your builidng official? Some may be comfortable w/ that, others not. Sometimes that may trigger a permit when you didn't intend to do that.
"I think I can assomplish the same R factor as with the foam."
Not with FG batts. FG batt simply allows free movement of air within it. Differences between densities of cold air next to the outside and next to the inside are substantial, and convective loops are induced. These are like little conveyor belts, carrying heat to the outside. This doesn't happen with foams or dense-packed cellulose. If not using a closed-cell foam, you'll have to be careful about sealing the edges of whatever is over the insulation so you don't have free movement of inside, humid air into the cavity.
Is there any existing insulation under the roof?
If there is, it can be a pain to butt to with new work. Not impossible, jsut a pain.
If you have bare structure, then you likely can just spray foam the entire assembly of new wall framing and panels and existing roof (complying with whatever rules your AHJ has, of course).
The vinyl-faced roll insulation typically used with metal buildings is not bad, but it's not a "snug" sort of feeling inside, either (which may be a catch-22 of commercial building than a flaw in the insulation design).