Updated July 9, 2025

WP-35 ALX™ Deck Drain: Designed for Superior Waterproofing Performance

When it comes to professional-grade waterproof deck systems, every component matters — including the drain. That’s why Westcoat developed the WP-35 ALX™ Deck Drain, a purpose-built drain engineered exclusively for use with our ALX and ALX Pro Waterproofing Systems.

Why Choose the WP-35 ALX™ Deck Drain?

This is not your typical store-bought drain. The WP-35 is a high-performance, marine-grade stainless steel drain, designed to integrate seamlessly into the ALX system for long-term waterproofing performance.

Key Features:

• Made from 26-gauge, marine grade 316 stainless steel for maximum corrosion resistance
• Includes a 4” round, bronze high-flow grate — made in the USA
• Large 12″ x 12″ flange and 4″ bowl with over 5.15 square inches of open flow area
• Meets ASME-A112.6.3 standards
• Easy to install and built for the ALX System’s exact specifications

This drain offers a premium solution for multi-family buildings, commercial balconies, rooftop decks, and any elevated surface using Westcoat’s ALX or ALX Pro systems.

Seamless Integration with ALX and ALX Pro Systems

The WP-35 Deck Drain is an integral part of our waterproofing system architecture. Whether you’re using ALX or ALX Pro, this drain is installed directly into the system layers — contributing to a durable, monolithic finish that enhances drainage without compromising waterproof integrity.

General Installation Overview

The WP-35 is installed after the sheet membrane is in place. Then the WP-25 Metal Lath is laid over the drain area, and our TC-1 Basecoat Cement is applied with WP-81 Cement Modifier. A 2” clearance is left around the drain cap to maintain proper slope and access.

For ALX Pro, WP-47 Fiberlath is used along with WP-90 Waterproofing Resin for additional reinforcement and flexibility. In both systems, the final Slurry, Texture, and Topcoat layers are installed up to the edge of the drain cap for a clean, functional finish.

For full installation instructions, consult the ALX or ALX Pro System specifications.

Resources for Specifiers and Installers

Looking to specify or install the WP-35? These downloadable resources are available to support your next project:

• WP-35 ALX Deck Drain Product Specification (pdf)
• WP-35 ALX Deck Drain Flashing Detail (pdf)
• ALX Standard Waterproofing System
• ALX Pro Waterproofing System 

How to Order the WP-35 ALX Deck Drain

The WP-35 is available exclusively through Westcoat. To learn more or place an order:

📞 Call us at 800-250-4519
📩 Or contact your local Westcoat Representative

Optimized for Performance. Backed by Westcoat.

From product innovation to field support, Westcoat is committed to delivering complete waterproofing systems — down to the last detail. The WP-35 ALX Deck Drain is another way we ensure your projects perform under pressure.