If you're planning a new build, insulation is one of those decisions that's worth thinking about early in the planning process.
If you just want to see the cost for insulation type plus labor, then read our article here on How Much Does Insulation Cost.
If you plan to heat or cool your building, work inside it year-round, protect temperature-sensitive equipment, etc., the right insulation will make a big difference.
Which insulation is right for your build? The answer depends on how you're going to use the building, your climate, your budget, and whether you're insulating the walls, ceiling, or both. There are several insulation options available for post-frame buildings, including fiberglass batts and rolls, spray foam, blown-in insulation, rockwool/mineral insulation, foam board, and reflective insulation.
In this article we're looking at spray foam vs fiberglass insulation. We'll give you a complete breakdown of each option and cover the most FAQs about them.
Spray foam is a great and often-used option for insulating a pole barn, particularly when air sealing and filling gaps are important considerations for the building's use. Spray foam is applied as a liquid and expands and hardens into an insulating material. Closed-cell spray foam generally has a higher R-value per inch than open-cell foam.
Spray foam installation can be more complicated than installing fiberglass insulation. We recommend using a professional spray foam installer unless you have experience working with the material.
This is a question that comes up often. Spraying foam against steel can be done in some applications, but the building design and installation method matter. Temperature changes can cause metal siding to expand and contract, and improperly installed foam systems can create problems with adhesion or condensation.
We recommend discussing the application for each individual situation with an experienced builder or insulation professional before deciding to spray foam directly against the metal panels.
Fiberglass blanket insulation is one of the most common insulation options, for pole barns and many other builds alike. Batts and rolls are designed to fit between the framing and can be installed in walls and ceilings. They're also relatively affordable and are a practical option for some DIY projects.
Standard fiberglass blanket insulation typically provides approximately R-2.9 to R-3.8 per inch, while higher-performance products can provide approximately R-3.7 to R-4.3 per inch.
Fiberglass does require proper safety precautions during installation. Gloves, long sleeves, eye protection, and appropriate respiratory protection should be used whenever you're working with fiberglass insulation.
There isn't one insulation type that's automatically best for every building project. Each has advantages and disadvantages depending on where it is being installed and what you're trying to accomplish.
R-value measures an insulation material's resistance to heat flow. Generally, a higher R-value means greater resistance to heat transfer.
The right R-value depends on several factors, including:
Milmar's insulation guidance recommends a minimum of approximately R-13 for walls and R-38 for ceilings.
For any building that you plan to insulate, choosing an insulation system appropriate for the local climate is very important because buildings may need to deal with significant temperature swings throughout the year. For example, insulation needs in Southern Indiana are different than insulation needs in Northern Michigan.
If you want to heat or cool your pole barn regularly, insulating both the walls and ceiling is the more complete and practical approach. Insulating only one portion of the building will leave other areas "leaking" the AC or heat.
A vapor barrier or condensation-control layer is often an important part of a pole barn's building plan, particularly when you're dealing with a metal roof.
Metal panels can experience condensation when warm, moist air meets a colder metal surface. Depending on the building (design, climate, and ventilation), this can lead to moisture dripping.
Reflective insulation or a properly designed vapor/condensation-control system can help address this. The exact assembly matters, though. A vapor barrier is not simply something that should be added anywhere without considering how the entire wall or roof system handles moisture. For that reason, it's smart to plan insulation, ventilation, and condensation control together.
Insulation isn't the only part of keeping a pole barn comfortable. Air leaks around doors, windows, wall transitions, roof penetrations, and other openings can allow conditioned air to escape and outside air to enter.
That's why a good insulation plan considers:
Note: Milmar includes rodent guard with its pole barns. While rodent guard isn't insulation, it helps seal the bottom of the building, keeps rodents out, and helps block drafts around the base.
The right choice ultimately comes down to what you're asking your building to do.
You may not need a full insulation package. You may not need any insulation! It depends on your year-round use of the space.
Wall and ceiling insulation can make the building much more comfortable, particularly if you're planning to heat it. And if you plan to heat the build, having insulation will of course make the build more economical in the long run.
You'll want to put more thought into the entire building envelope, including insulation, air sealing, condensation control, and the HVAC system.
Your insulation needs will depend heavily on the building's use and whether temperature control is necessary. Feel free to contact our team to ask about your specific use-case and what they would recommend.
Insulation becomes an important consideration because the building is functioning as a home. Your insulation, air sealing, vapor control, windows, doors, HVAC system, and other components should all be designed carefully.
A big mistake you can make with a new build is treating insulation as an afterthought. If you know from the beginning that your building will eventually need some type of insulation, tell your builder during the design process. That gives you the opportunity to plan the framing, ceiling, interior liner, doors, windows, ventilation, electrical, and insulation as one system. It doesn't have to even all be done by the builder you are using - you can always add later. But designing the build with future plans in mind is always your best option.
Check out these linked topics to learn more about pole barn and garage designs, how much does it cost to build a garage, and our last insulation costs and options article.