Underlayment Lives in a Tough Environment

Under metal roofing, the hidden underlayment can experience substantial heat.

That is why products specifically rated for high-temperature roofing applications exist.

Polyglass, for example, markets high-temperature self-adhered underlayment specifically for steel, aluminum, copper, and other high-temperature roof coverings.

Why Not Use Any Underlayment?

Products have different:

• Temperature ratings
• Adhesives
• Exposure limits
• Installation requirements

The selected underlayment needs to be compatible with the roof system above it.

Is Underlayment the Main Metal Roof?

No.

It is a secondary layer beneath the panels.

But it can contribute to water management if moisture reaches beneath the metal.

Why Does Installation Matter?

Underlayment still needs correct:

• Overlap
• Flashing integration
• Surface preparation

Compare Systems, Not Just Panels

A metal-roof quote should identify more than the visible steel.

The Best-Looking Metal Panel Still Depends on the Layers Beneath It.

Envirotech Exteriors plans the roof as a complete assembly, including underlayment, panels, flashing, fasteners, and ventilation.