Rising energy costs and a heightened global focus on energy efficiency mean getting the most out of your heater and reducing structural heat loss is more critical than ever. One of the most effective ways to achieve these goals is through insulation; one of the most cost-effective ways to insulate the space you’re building or designing is with a polyisocyanurate installation for your roof.

A Breakdown: Polyisocyanurate

Known as “polyiso” for short, polyisocyanurate installation is one of the world's most widely used building materials, accounting for more than 75% of the insulation used in commercial building construction in North America. 

It’s most commonly used as continuous insulation for roofs or as a protective roof cover board. A closed-cell, rigid foam board bonded to facers on both sides of the board, polyiso is predominantly composed of organic materials, including polyol, a blowing agent and polymeric methylene diphenyl diisocyanate [MDI]. 

This formulation, coupled with its use with different facers, imparts several benefits to the user: 

  • compatible with a variety of roofing systems;
  • third-party certified long-term thermal performance;
  • low global warming potential blowing agents, and; 
  • industry-wide Environmental Product Declaration [EPD]. 

Given all of this, it is no surprise that polyiso is the most widely used product for low-slope commercial roofing.

While polyiso is essentially equal to gypsum — a popular alternative — in features like moisture resistance, fire resistance and other uplift properties, the advantages of polyiso are stark: it is lighter, easier to ship, and simpler to maneuver around a roof. In fact, polyiso cover boards can protect the underlying insulation from roof traffic and allow the roof to be used for renewable energy systems such as a rooftop solar power system. 

Polyiso also provides a high R-value, the unit of measure indicating how effectively a product insulates. High R-values mean the material is better at its job, an inherent benefit of polyiso cover boards. With contemporary energy codes instituting minimum insulation requirements, polyiso is an excellent choice to meet and even exceed those standards.

Easy to Install, Good for the Environment

Installing polyiso insulation on any roof will contribute to the building’s overall thermal efficiency, making it more fire-resistant and helping cut energy costs. The global warming potential [GWP] of the blowing agents used when manufacturing polyiso insulation is essential when evaluating its environmental impact. 

GWP compares gases to determine their global warming impact, specifically how much energy the emission of one ton of a particular gas will absorb relative to one ton of carbon dioxide in a given amount of time. 


North American manufacturers use pentane, a hydrocarbon with zero ozone depletion potential [ODP], and low-GWP blends, known as pentane, to produce polyiso insulation products. Pentane’s GWP value of less-than-10 means polyiso insulation products produced and sold in North America comply with climate regulations that restrict the manufacturing or installation of products with higher GWPs. 

Science aside, this means contractors can confidently recommend polyiso insulation products knowing they comply with any regulations. By effectively creating protective air barriers on top floors, sealing off a building from the outside elements, and decreasing the need for large heating and air conditioning units, polyiso saves energy in more ways than one. 

The unique structure of polyiso leads to its exceptional fire-resistant properties. Isocyanurate chemical bonds lead to high-temperature invulnerability of nearly 390 degrees Fahrenheit, more than double that of most insulation foams. This makes polyiso less susceptible to surface burning and can help prevent flames from spreading. With the stringent criteria of codes related to fire performance in commercial buildings, contractors will have much more flexibility when insulating roofs with polyiso.

Polyiso insulation has always been a leading choice for commercial roofs, and new technological advancements in the formula continue to make it more economical and environmentally friendly. 

Polyiso insulation has always been a leading insulation choice for commercial roofs, and new technological advancements in formula makeup continue to make it more economical and environmentally friendly. Elevate’s ISOGARD polyiso insulation is one such solution for commercial roofing challenges. Its thermal performance is up to 40% better than major competitors when tested by an independent third party in cold temperatures, 40 degrees Fahrenheit, 4 degrees Celsius, applications according to ASTM C1289 standards.

When building or designing roofs this winter, consider polyiso insulation to save on energy costs while staying warm.