What Types of Metal Building Insulation Systems are Available?

Selection of Metal Building Fiberglass Insulation –

Proper installation of insulation is vital for a metal building in terms of energy conservation, interior climate control and overall sustainability. Insulation can minimize condensation and regulate indoor ambient temperatures, which are crucial features to moderating metal building facilities. Both cold and heat are conducted easily throughout metal buildings because they have no inherent R-Value rating without optimum insulation systems.

When seeking insulation for metal building, the term ‘R-Value’ is crucial. The ‘R’ refers to resistance to heat flow. The greater the R-value, the higher the competency there is in the insulation product. The thickness of fiberglass is directly proportional to the R-Value. (The relative thickness of fiberglass is equivalent to increased insulation power)

Single-layer Insulation systems include up to 6” R-19 fiberglass blankets which can be installed on top of purlins and sandwiched between the outer panels. Longer fasteners are required for 6” fiberglass for over the top of purlin applications. The range of Single Layer R-Value systems spans from R-8 to R-30 (from 1-5/8” to 9.5”)

Double-Layered Insulation systems provide optimal insulation; providing enhanced energy conservation. The range of Double-Layered R-Value systems span from R-29 to R-30 (from 3” to 9.5”)

Insulation Facing

A vinyl or polypropylene material is laminated over the fiber-glass blankets and provides vapor retarder benefits. More often than not, the facing is white. That is not always the case however, as black facing is used occasionally within the industry. This protects the insulation from condensation and imparts a refined appearance to the fiberglass insulation. The range of insulation facings below includes Light to Heavy Duty.

WMP-VR is a Light-Duty economical insulation

WMP-VR-R is Standard-Duty insulation, with 50% increased bursting strength and a polyester backing.

WMP-10 is Standard-Duty insulation with a metalized polypropylene facing.

WMP-50 is a Heavy-Duty insulation, which is twice as heavy, also with a polypropylene facing and has a higher abuse resistance.

GYMGUARD is a Heavy-Duty insulation with a fiberglass-polyester woven back with exceptional high-impact strength


Tabs are used to create the finished seal at the seams of the insulation. New construction commonly uses 1-6” tab and 2”-3” are more commonplace in retro-fitted applications. A mutual preferred option is a taped tab with pre-applied double face tape on the tab for a quick seal to the joints.

Banding Systems

Banding systems are normally used in single-layer retro-fit applications or in double-layer applications for new construction. Double-layer systems offer the highest R-Values. Upgraded insulation packages are more economical over the long-term (up to R-38); offering the highest energy conservation and banding systems are preferred whenever attaching insulation to structures that require climate control. The double layer thickness is commonly determined by the depth of the metal building purlin. For instance 8” deep can accommodate 8” R-25 fiberglass insulation and 12” can accommodate 12” R-38 fiberglass.

Retro-fit Systems

For existing buildings, retro-fit packages are available when upgrading the insulation system in an existing metal building, pole barn or pole building and can be installed to cover unsightly torn existing insulation. Factory pre-cut to fit, white vinyl-faced fiberglass blankets are placed in-between the metal roof purlins and held in place by steel strapping or for pole buildings a nail with a large white plastic washer. Roof purlin spacing on a metal “red Iron” building is variable (5’ on center and 8” depth is common). Retro-fit white faced fiberglass enhances interiors and provides an additional insulating value of with single layer blankets up to 9.5” R-30 performance. This system design attains the highest insulating value to the structural components of a building. We recommend that you chose an insulation thickness that fills the purlin cavity to avoid an airspace that may create or hold condensation.

Foam Insulated Panels –

Over the past few decades, insulated panels have become increasingly popular in metal building construction. These panels provide exceptionally high r-values, superior moisture and sound control, and unmatched thermal performances, all while reducing labor time and costs. The pre-engineered panels are manufactured and delivered to site ready for erection. With a variety of thicknesses and metal finishing options, foam insulated panels are excellent choices for any metal building project.

Dual Layer Insulation Kit
Metal Building Insulation Install