How the AmeriDex Dryspace System Works
Integrated PVC decking and Dexerdry seal stop water at the surface and create dry, finished space below.
The Two-Part System
One product. Two engineered components working together.
Cellular PVC Deck Boards
Premium cellular PVC core with a proprietary ASA cap. Will not rot, splinter, or warp. Authentic grain. Generational lifespan.
Dexerdry Integrated Seal
Automotive-grade TPE seal engineered to lock between every board. Diverts every drop of rain and snowmelt off the deck and away from the framing below.
How It Works in 3 Steps
Frame your deck like normal.
Standard joist layout, standard framing, no special substructure. AmeriDex installs on a conventional frame at 16" o.c.
Install AmeriDex boards with the integrated Dexerdry seal.
Interlocking fit creates a continuous water-diverting deck surface.
Water sheds away. Under-deck space stays bone dry.
Rain runs across the deck, gets carried out by the seal, and falls clear of the joists. The space below stays dry, finished, and usable.
Why New Construction Only
AmeriDex is engineered into your build from the joists up. That is exactly why it works. Retrofit drainage systems hang underneath your deck and fail. AmeriDex is the deck.
Specs At A Glance
| Board | Cellular PVC with proprietary ASA cap |
| Seal | Dexerdry automotive-grade TPE |
| Profile | Tongue-and-groove with integrated water-diverting seal |
| Lengths | 12 ft, 16 ft, 20 ft. Custom lengths available on request. |
| Joist Spacing | 16" o.c. residential |
| Fasteners | Starborn epoxy-coated screws or stainless screws and plugs (sold separately) |
| Warranty | 25-Year Residential, 10-Year Limited Commercial |
| Fire Rating | Class A flame spread (ASTM E84) |
| Application | New deck construction only |
Frequently Asked Questions
Everything builders, dealers, and homeowners ask before specifying AmeriDex.
What makes AmeriDex different from other under-deck drainage systems?
AmeriDex is an above-joist, integrated system. The waterproofing happens at the deck surface itself, not in a tray hung underneath the framing. Competing retrofit drainage systems are added below an existing deck as a tray or panel hung from the joists. AmeriDex is engineered into a new deck from the joists up, which is why your joists, beams, and ledger stay dry for the life of the structure.
Can AmeriDex be installed on an existing deck?
No. AmeriDex is engineered for new deck construction only. The Dexerdry TPE seal locks between every board as the deck is installed, so it has to be built into the project from the start. Trying to retrofit it onto an existing deck would require removing all of the existing deck boards.
What is the Dexerdry seal and what is it made of?
Dexerdry is the integrated drainage seal that ships between every AmeriDex deck board. It is made from automotive-grade TPE (thermoplastic elastomer), the same material category used in car door and window seals. It is engineered to flex through years of thermal cycling without cracking or losing its watertight fit.
What are AmeriDex deck boards made of?
AmeriDex boards are premium cellular PVC with a proprietary ASA cap. They will not rot, splinter, or warp, and they carry an authentic wood grain finish. They are made in the USA.
What joist spacing does AmeriDex require?
AmeriDex installs on a conventional 16 inches on-center joist layout for residential applications. No special substructure, sleepers, or sub-framing is required.
What lengths and colors are available?
AmeriDex deck boards are stocked in 12, 16, and 20 foot lengths and in seven PVC colors. Custom lengths are available on request for projects with non-standard runs. You can request free samples to see all seven colors in person.
What is the AmeriDex warranty?
AmeriDex carries a 25-year residential limited warranty and a 10-year limited commercial warranty on the deck board system.
What is the fire rating of AmeriDex deck boards?
AmeriDex cellular PVC deck boards carry a Class A flame spread rating under ASTM E84, the highest flame spread classification for building materials. That makes the boards a strong fit for projects in wildfire-prone regions and for jurisdictions that require Class A surface burning performance on the walking surface.