Last updated: October 10, 2026.

Roof color is often treated as an aesthetic choice, but surface properties also affect how much solar energy a roof absorbs. That is the basic idea behind “cool roofs.”

Reflectance and Emittance Are Different

Solar reflectance describes how much sunlight the roof reflects. Thermal emittance describes how effectively the surface releases absorbed heat. Both influence roof temperature.

Light Color Helps, but Technology Matters Too

Some products use reflective pigments or coatings that can improve solar performance without looking bright white. Product ratings are more useful than judging performance by color alone.

Climate Changes the Value

A roof that reduces summer heat gain may be more valuable in a hot climate than in a heating-dominated climate. DOE also notes that cooler roofs can increase heating needs during cold seasons in some situations.

The Roof Is Only One Part of Comfort

Attic insulation, air sealing, ventilation and HVAC condition all affect indoor temperature. A reflective roof will not compensate for major problems elsewhere in the building envelope.

Replacement Timing Matters

If the roof is already near the end of its life, comparing reflective options may make sense. Replacing a sound roof early just for energy savings can be a very different financial decision.

What We’d Ask a Roofer

• What are the product’s solar reflectance and thermal emittance ratings?
• Are those initial or aged values?
• How does the product perform in our climate?
• Does the warranty differ from standard roofing?
• Is the reflective option a large price premium?

Related reading: Roof checks before a major storm · Attic moisture and roof ventilation

The Bottom Line

Cool roofs can reduce solar heat gain, but the best choice depends on climate, roof condition, product performance and total project cost—not simply choosing the lightest color available.

Sources: U.S. Department of Energy — Guidelines for Selecting Cool Roofs; DOE Energy Saver — Cool Roofs.