Trex RainEscape® Post Flash

Seal Around Deck Posts for Complete Water Protection

Trex RainEscape® Post Flash is a smart finishing touch for your Trex RainEscape Under-Deck Drainage System. Designed to create a watertight seal around deck posts that penetrate the system, this flexible flashing prevents water from leaking through post openings—protecting the area below from moisture, stains, and long-term damage.

Product Features:

• Seals Post Penetrations – Prevents water intrusion where deck posts pass through the drainage system

• Flexible, Conformable Design – Fits tightly around standard post sizes and adapts to the shape of your installation

• Durable and Long-Lasting – Made from tough, weather-resistant material for years of protection

• UV and Weather Resistant – Built to withstand harsh outdoor conditions without degrading

• Clean, Professional Finish – Provides a neat appearance while adding essential protection

Specifications:

• Fits: Standard 4" x 4" posts

• Material: Flexible weatherproof polymer

• Color: Black

• Application Surface: Trough openings around vertical support posts

• Compatibility: Designed for use with Trex RainEscape troughs and overall system

Installation Tips:

• Slide over post before installing the decking surface

• Apply after cutting the trough to fit around the post

• Secure with Trex RainEscape Butyl Caulk or Tape to ensure a watertight seal

• Use in combination with other RainEscape components for full drainage system coverage

Finish your under-deck drainage system with Trex RainEscape Post Flash to ensure every detail is sealed and protected—so your outdoor living space stays dry, clean, and long-lasting.