This quantity of boards will cover up to sq ft

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Constantly improving on their innovative RainEscape drainage system, Trex offers Post Flashing for 4 inch x 4 inch wood posts to further prevent moisture penetration. The snug-fitting collar slides over a 4 inch x 4 inch post and is secured with a bead of RainEscape caulk (sold separately) as well as RainEscape butyl tape (sold separately). A post sleeve can fit over the wood post and the Post Flashing. If there isn't a post sleeve, you can trim the Post Flashing to the same height as your deck boards to completely conceal the Post Flashing.

Give us a call at 1-888-824-5316 and our team of project planners will help you estimate how much of everything you'll need.

The Trex RainEscape deck drainage system is designed for easy DIY installation, whether your joist spacing is 12-inch or 16-inch on-center.

Please note, this system can only be used for new projects; it cannot be installed on an existing deck.

DecksDirect # 6272

Trex RainEscape Post Flashing Installation Instructions (2.14 MB) 

Trex RainEscape Installation Sheet (2.23 MB) 

Trex RainEscape Installation Instructions (9.50 MB) 

Trex RainEscape Warranty (19 KB) 

Pack SizeEach
Compatible Post SizeNominal 4 in x 4 in
Overall Dimensions
(width x depth x height)
6-1/2 in x 6-1/2 in x 3-1/2 in
Inside Dimension3-1/2 in x 3-1/2 in
Material TypePVC
Included AccessoriesNone
WarrantyView Trex RainEscape Warranty Information
Questions & Answers