When insulating a roof, it's important to educate your commercial clients about the significant financial and environmental benefits of properly installed, energy efficient roof insulation.
On average, 30% of energy used in commercial buildings is wasted, according to the U.S. Department of Energy. In fact, just by upgrading existing commercial roofs with energy efficient insulation, commercial building operators could save more than $65 billion in energy costs over the next 30 years.
As a roofing contractor, there is incredible opportunity for business growth when you harness the national shift toward more sustainable building practices. It can potentially help you to broaden your markets, increase revenue, build customer satisfaction, and reduce carbon emissions for the planet.
Here's a look at the finer points of commercial roofing insulation, including materials, installation best practices, considerations around navigating budget and cost drivers, as well as maintenance logistics.
Types of Roof Insulation for Commercial Projects
The best roofing insulation for a commercial project isn't all about cost. The most common insulation materials—ISO, XPS, and EPS—each have unique qualities that can guide your selection based on variables like local climate, roof weight load requirements, local building code, and customer budget.
Polyisocyanurate (ISO)
Closed-cell foam ISO insulation, which is typically sandwiched by glass fiber-reinforced cellulosic felt facers, reinforced mat facers, or coated glass facers, is favored for its versatility, energy efficiency, and durability.
R-value: Known as offering the highest R-value per inch, ISO was traditionally preferred for temperate climates, since lower temperatures could decrease thermal efficiency. More recent technology has created ISO products that offer high-performance thermal efficiency in nearly every climate. For example, the EnergyGuard™ NH Polyiso Insulation is a flat, non-halogenated polyiso insulation panel with low-temp, stable R-value at 40 and 75 degrees mean temperature, which helps it contribute toward sustainability certifications.
Compressive strength: ISO offers a range of compressive strength, based on project need. For example, both the EnergyGuard™ HD and EnergyGuard™ HD Plus Polyiso Cover Board have R-values of 2.5, (higher than any non-polyiso cover board). Made with high-density polyiso foam core and coated glass facers (Grade 1: 80psi, Grade 2: 110psi, and Grade 3: 140psi) they protect against the elements, moisture, and traffic.
Other benefits: Fire resistance, and new levels of moisture and mold resistance.
Expanded Polystyrene (EPS)
Both EPS and XPS have a polymer base, but different manufacturing processes. EPS is manufactured using a blowing agent and steam to mold the final product. That said, this material may have lower moisture resistance due to cell structure, so be sure to check building and environmental needs.
R-value: Typically lower R-value than both ISO and XPS, making it better suited to warmer climates. Averages may range from 3.6 to 4.2.
Compressive strength: EPS offers the lowest load-bearing capacity, so it may not be advisable for commercial roofs with greater load-bearing capacity needs, like large-scale HVAC equipment or heavy traffic.
Other benefits: Often a lower price point, making the upfront cost more accessible.
Extruded Polystyrene (XPS)
Unlike EPS, which uses steam in manufacturing, XPS is manufactured from blowing agents, heat, and an extruding machine. As a result, XPS is typically considered to be more durable and often preferred over EPS for high moisture situations and/or heavy load-bearing capacity.
R-value: Although ISO could typically offer higher R-value psi than XPS, it didn't have the same consistent thermal performance as XPS in colder climates. Now, some ISO can perform with the same thermal consistency as XPS, offering greater energy efficiency year-round and in many climates.
Compressive strength: XPS may offer standard grades from 25-40 psi, and high-density grades up to 100 psi—which is suitable for heavy commercial building load requirements like solar panels, HVAC systems, etc. Of note, newer technology has brought some ISO offerings (such as EnergyGuard™ HD and EnergyGuard™ HD Plus Polyiso Cover Board) into competition with XPS with regard to compressive strength.
Other benefits: Durable and moisture resistant.
Cost Factors to Consider
The cost of insulating a roof with the proper material can vary based on project size, insulation thickness, and product type. For project guidance, turn to experts like your local GAF Territory Manager or the GAF Building & Roofing Science team.
Educating customers about available cost savings and the long-term ROI of proper insulation can be supported by sharing powerful data like these analyses from PIMA:
Installing an energy code-compliant roof replacement in Climate Zone 2, Tampa, Florida (R-25) is estimated to generate whole-building energy savings of 2% to 3% annually depending on the building type. This translates into energy cost savings per square foot of $1.72 to $2.73 and carbon equivalent emissions reductions per square foot of approximately 18 to 32 lbs.
Installing an energy code-compliant roof replacement in Climate Zone 4, New York City, New York (R-30) is estimated to generate whole-building energy savings of 5% to 10% annually depending on the building type. This translates into energy cost savings per square foot of $2.55 to $4.90 and carbon equivalent emissions reductions per square foot of approximately 32 to 81 lbs.
Proper Installation Techniques
Quality roofing insulation only operates at maximum efficiency when installed precisely, following manufacturer guidelines. Here is a helpful GAF video that walks through the steps involved:
Prioritizing Maintenance and Inspection for Longevity
You can position yourself as a commercial roofing leader by offering ongoing support to customers with routine inspections and regular communication. Catching minor issues before they grow into problems can save you—and your clients—time and money.
Indicators that a commercial roof may need repairs could include:
Blistering or bubbling
Sagging
Decreased energy efficiency or thermal inconsistencies
Visible damage
Damaged flashing
Leaks or moisture collection
Any other abnormalities
Helping Commercial Clients Understand Their Insulation Needs
As a roofing contractor, knowing the right insulation type and proper installation techniques for every situation can provide an incredible opportunity for business growth. As a commercial roofing contractor, you're uniquely positioned to educate customers about long-term ROI, sustainability and building longevity, and the reduction of harmful emissions. Plus, you can potentially increase client satisfaction and reduce callbacks when the roof operates efficiently.
Curious to learn more? Discover GAF commercial roofing insulation insights and explore premium products like GAF EnergyGuard™ Polyiso Insulation.
