An Overview of
Metal Building Insulation

If you're thinking about insulating your metal building or structure, there are a few factors to consider. You know you want to keep the cool air in during the summer, and the warm air in during the winter, but what kind of insulation should you use? Do you need a vapour barrier? And just what is an R-value?


Norsteel has enlisted the help of metal building insulation-expert, Robert Tiffin, National Accounts Manager for the industry-leading insulation manufacturer Silvercote, to help describe some of the common forms of metal building insulation. Continue reading below for an overview of everything you need to know when it comes to insulating your metal building.

What is Insulation?

Insulation is any material used to cover, line, or separate which also prevents or reduces the passage, transfer, or leakage of heat, electricity, or sound. There are many types of insulation available on the market, but depending on your local energy codes and the intended use of your structure, you may be forced to use a particular form of insulation.

There are four main types of insulation used in metal building structures:

  • Glass wool (aka Fiberglass);
  • Mineral wool;
  • Spray foam (check with metal building manufacturer on whether your structure can accommodate this form of insulation);
  • Polyisocyanurate (sometimes called "Poly-iso") rigid board insulation.


As mentioned, depending on compliance requirements in your specific climate zone, municipal or regional codes may call for combinations of insulation products including faced glass wool and poly-iso rigid board. If the use of rigid board is cost-prohibitive there are alternative assemblies which meet the requirements of the standard/code.

Fiberglass Insulation with foil facing

Fiberglass insulation with a foil facing.

What is Facing?

Put simply, facings are barriers which are attached to insulation to protect the surface of the insulation, hold it together, or act as a vapour retarder (see image above of fiberglass insulation with a foil facing).


Most commonly however, manufacturers attach a facing to act as a vapour barrier and/or air barrier. Facings are engineered to protect insulation from physical abuse, control moisture migration, and where necessary to meet fire codes and standards. Vapour retarders can be composed of vinyl, polypropylene, polyethylene, foil, or metalized polyester.

Why Insulate My Metal Building?

In simple terms, insulating your metal building will help keep the heated interior space warmer in the winter, and air-conditioned spaces cooler in the summer. Regardless of where you live, if you plan on using your metal building for human occupancy of any kind, it is generally recommended that you insulate your strcuture.


Here are just a few potential benefits that come from insulating your metal building:

  • Insulation reduces energy costs (in a conditioned building);
  • Insulation prevents moisture condensation. When temperature and dew-point are at the right combination, you will have condensation build up on your building's roof and walls. This could result in water raining down in your building;
  • Insulation helps with acoustical performance, reducing noise levels. Most forms of insulation have acoustical and sound absorption properties which reduce interior reverberations and prevent transmission from exterior;
  • Insulation helps maximize your return on investment (ROI). The insulation acts as a barrier between metals, that in the presence of condensation could otherwise lead to rusting.
Mineral Wool metal building insulation

Mineral wool insulation.

Spray Foam metal building insulation

Spray foam insulation.

Poly Iso metal building insulation

Poly-iso board insulation.

Oh, and What is an R-Value?

R-value refers to the ability of the insulation to resist thermal transmission (conductive heat flow). The higher the R-value, the greater the insulating effectiveness.


Single and multi-layer faced and unfaced cavity fill glass wool is the most typical seen in conventional construction. (R2.9 – R3.8 per inch (25.4 mm)). By far the most common type of insulation sold for prefab Steel building systems, is fiberglass laminated blanket insulation. Easy to install and cost effective, blanket insulation is available in several R-Values for both roof and walls.


Mineral wool is primarily composed of basalt (volcanic/igneous rock), and commonly used in fire-rated wall assemblies.  It has a higher R-value per inch than glass wool. (R3.0 – R3.3 per inch (25.4 mm)).


Poly-Iso board has a high R-value per inch so is good for use when needing a consistent, uncompressed or continuous insulation where limited space is available. (R6.2 per inch (25.4 mm)).


Spray foam insulation materials can be sprayed, foamed-in-place, injected, or poured. Foam-in-place insulation is blown into wall cavities to insulate and reduce air leakage. Some installations can yield a higher R-value than traditional insulation for the same thickness, and can fill even the smallest cavities, creating an effective air barrier. (R3.6 – R4.3 per inch (25.4 mm)).

Speak with your metal building manufacturer for their recommendations, as factors such as energy codes, cost, installation techniques should all be considered before making your decision.

About the Author

Robert Tiffin is the National Accounts Manager for Silvercote, an industry leader in custom insulation solutions. Robert drives change daily in the Metal Building Industry in his Architect Committee Chair role with the MBMA, as the Marketing Chair of the MBCEA and other industry/policy committees within NIA, ASHRAE and SEEA. In August 2014, Robert became the National Accounts Manager of Silvercote - a leading manufacturer, laminator in custom insulation solutions for the industrial, commercial and residential industry. Prior, Robert was active in the management and daily transactions of the Metal Building Inside Sales Team, and Strategic Accounts.


While at Guardian Building Products Group from 2001 to 2014 (before the KNAUF acquisition) Robert was elevated from an Inside Fiberglass Sales role to Manager of the Eastern US Building Materials Traders with a challenge to increase sales productivity. Robert motivated a collaborative sales and distribution team to build unique customer relationships that delivered significant revenue and market share growth.


Robert Tiffin Headshot Silvercote

Robert, and his wife, Barbara, have two amazing college age kids, and live in the Upstate of South Carolina.


Contact Norsteel Today!

Today’s Pre-engineered steel buildings are energy efficient by design, engineering and construction. They are used for a multitude of unlimited purposes. This dictates that every prefab metal building system has individual requirements in terms of insulation. Pre-engineered metal buildings are compatible with several insulation options. All of these increase thermal efficiency and provide sound resistance.


Whether you are only interested in accounting for condensation, or whether you are heating a retail outlet or restaurant; it is important to discuss your heating and cooling requirements with your Norsteel Building consultant so that you can explore all the options available to you.


If you're considering insulating your metal building, you need a team of experts who can help navigate functionality, costs, and local building requirements. When you engage Norsteel we become your partner throughout the entire construction process. Click here to contact us today for a free, no obligation quote on your next building project!


Robert Tiffin Headshot

Robert Tiffin
National Accounts Manager, Silvercote