25-yr residential / 10-yr commercial warranty Free quote + free samples

Build the deck. Keep the space underneath.

AmeriDex is the only above-joist Dryspace system where the cellular PVC boards and the patented Dexerdry seal lock together at install, so 100% of rain runs off the deck instead of into your joists.

Made in Linden, NJ 25-year residential warranty Patented Dexerdry seal
See how the system works

Deck Board Colors

Visualize the perfect finish for your AmeriDex system.

AmeriDex Driftwood cellular PVC deck board color sample

Driftwood

Solid
AmeriDex Khaki cellular PVC deck board color sample

Khaki

Solid
AmeriDex Slate cellular PVC deck board color sample

Slate

Solid
AmeriDex Beachwood cellular PVC deck board color sample

Beachwood

Variegated
AmeriDex Chestnut cellular PVC deck board color sample

Chestnut

Variegated
AmeriDex Redwood cellular PVC deck board color sample

Redwood

Variegated
AmeriDex Hazelnut cellular PVC deck board color sample

Hazelnut

Variegated
American Made Produced in the USA
Integrated Waterproofing Seamless protection
Premium PVC Decking Durable and low-maintenance

This is happening above your head right now.

Every rainstorm sends water through the gaps in a normal deck. It soaks the joists, rots the framing from above, and drips on whatever is below. Composite boards do not fix it. They hide it. Most homeowners do not see it until a contractor pulls a board in year 12.

AmeriDex is the only system that stops it on day one.

See how AmeriDex stops it

Why an above-joist Dryspace system wins

The AmeriDex water-diverting system stops every drop at the surface, before it ever touches your joists or beams.

Cross-section of the AmeriDex board and Dexerdry seal assembly: two cellular PVC deck boards with a Dexerdry TPE seal compression-fitted between them, V-shaped drainage gap below Your deck
becomes its own roof
Every drop diverted
at the surface
Dry living space
that lasts the life of the deck
AmeriDex assembly cross-section: cellular PVC deck boards locking onto the Dexerdry TPE seal

Above-Joist vs Below-Joist: The Real Difference

Most under-deck drainage systems are retrofits. AmeriDex is engineered into the deck itself.

An above-joist deck drainage system stops water at the walking surface. The waterproofing happens between the boards, on top of the joists, before a single drop reaches the framing. AmeriDex is built this way. Cellular PVC deck boards lock onto the Dexerdry TPE seal as the deck is installed, so 100% of the rain is diverted off the deck and away from the structure.

Below-joist, retrofit drainage systems are different. They are tray, panel, or membrane assemblies hung underneath an existing deck after the boards are already in place. Water still falls through the gaps in the deck boards, soaks the joists and beams, and is caught in a tray below. Over time, those wet joists can rot, fasteners can corrode, and stains can bleed through onto the panels.

If you are building a new deck and you want a real dry space under the deck, integrated above-joist drainage is the only way to keep your framing dry for the life of the structure. See the full above-joist vs below-joist comparison, read the deeper above-joist deck drainage explainer, or learn about AmeriDex and the patented Dexerdry seal behind the system.

See what your under-deck space can become

Outdoor kitchen. All-weather lounge. Year-round play zone. The same square footage you already paid for, finally usable in any weather.

Outdoor Kitchen: covered cooking and dining zone that stays usable in rain
Lounge Area: turn the space under your deck into an all-weather living room
Kids Play Zone: give kids a dry place to play, even when the weather does not cooperate

A piece of the system, on us.

Tell us where to send it and we will mail you a real cut of an AmeriDex board and a piece of the Dexerdry seal. Hold it. Bend it. Pour water on it. Show it to your builder.

No one will call. No follow-up unless you ask for it.

Ship my free samples

What does it cost not to have AmeriDex?

A new pressure-treated frame in 12 years runs into the thousands for an average NJ deck, plus tear-out of whatever sits on top of it, plus the lost use of the yard during the rebuild.

The AmeriDex Dryspace System is engineered so you only build that frame once. For most NJ-shore homeowners, the system pays for itself the first time the neighbor's deck has to come down.

Spring NJ install windows are filling.

Most AmeriDex builders book their season early. Get on the calendar now and we will match you with an authorized AmeriDex installer near you.

AmeriDex Dealer Portal