Why Is One Small Area of Siding Melting?

The siding is not near:

• A barbecue
• A fire
• An exhaust vent

Yet one area looks:

• Wavy
• Shiny
• Distorted
• Partially melted

Look across the property.

A neighbouring or nearby window may be reflecting concentrated sunlight onto that wall.

Can Window Reflection Really Get That Hot?

Yes, under unusual conditions.

CertainTeed’s installation guidance warns that concentrated sunlight reflected from glass or other highly reflective surfaces can create enough heat buildup to distort or melt vinyl siding.

Why Is the Damage Localized?

The reflection may focus sunlight onto a relatively small area.

As the sun changes position, the concentrated path can move.

Is This the Same as Normal Siding Warping?

No.

Normal buckling often relates to:

• Fastening
• Expansion clearance
• Installation

Solar-reflection damage is a heat-concentration problem.

What Can Be Done?

The reflective source should be identified before simply replacing the damaged siding.

CertainTeed suggests strategies such as interrupting the reflected sunlight with appropriate screens, awnings, or landscaping.

Replace the Damaged Panel—and Address the Heat Source That Damaged It.

Envirotech Exteriors can help distinguish installation-related siding distortion from localized heat damage.