# WPC weathering: UV fading and hot surface temperatures

Canonical: https://woodplasticcomposite.net/guides/wpc-uv-fading-surface-temperature/
Language: en
Updated: 2026-10-01
Version: 1
Review: Technical and language review not yet recorded

## Summary

Appearance, surface temperature and structural condition are related but distinct. Assess each with suitable evidence rather than treating one result as a complete weathering assessment.

## The technical principle

Sunlight can change pigments, natural fibres and polymer surfaces. Colour shift does not by itself prove structural failure, and retained colour does not prove unchanged mechanical performance. Darker surfaces often absorb more solar energy, but actual temperatures also depend on exposure, airflow and surface properties.

https://woodplasticcomposite.net/guides/wpc-uv-fading-surface-temperature/#technical-principle

## What to specify and verify

Request the weathering protocol, exposure duration and measured colour change, together with relevant retained properties. Compare samples in consistent lighting. For barefoot-use areas, assess heat exposure and comfort separately from slip testing, and consider shading or other design responses.

https://woodplasticcomposite.net/guides/wpc-uv-fading-surface-temperature/#specification

## Application and common mistakes

Do not use outdoor air temperature as a guaranteed maximum board temperature. Do not convert a stated number of laboratory exposure hours into years without a validated relationship. Set realistic appearance expectations before purchase and keep a sample for future comparison under comparable viewing conditions.

https://woodplasticcomposite.net/guides/wpc-uv-fading-surface-temperature/#application

## Discuss your project with Green Plank

For a Green Plank specification, request samples and current technical documents for the exact profile and intended application. Use the Green Plank link in Sources to explore the range and make an enquiry. Commercial disclosure: this portal features Green Plank. General material science does not certify any particular product.

https://woodplasticcomposite.net/guides/wpc-uv-fading-surface-temperature/#green-plank-project

## Key points

Appearance: Measured colour change and conditions.
Comfort: Surface temperature in intended use.
Integrity: Relevant retained material properties.

## Comparison

Specification check | Evidence to request
Appearance | Measured colour change and conditions
Comfort | Surface temperature in intended use
Integrity | Relevant retained material properties

## Does fading mean the decking has failed structurally?

Not necessarily. Assess appearance requirements and structural condition separately.

## Sources

1. Klyosov, A. A. (2007). Wood–Plastic Composites. Chapters 15 and 16; pp. 550–556, 585–590. — https://doi.org/10.1002/9780470165935
2. Green Plank — product information and technical enquiries — https://greenplank.eu/