What is a Puddle Flange? A Complete Guide

A puddle flange, sometimes called a leak control flange, is an essential construction product that ensures a secure connection between waterproofing membranes and drainage systems (DWV – Drain Waste Vent). Required by Australian Standard AS 3740-2010, puddle flanges are vital in preventing water leaks and protecting surrounding structures from moisture damage.

There are two main variations: those designed for tiled floors and those intended for vinyl floors. Each performs the same fundamental role but is adapted to interact with the different flooring systems.

Tiled Floor Puddle Flanges
A tiled floor puddle flange is generally manufactured from PVC and is approximately the size of a dinner plate, providing a generous bonding area for waterproof membranes. Installed within a rebated section of the floor substrate, it creates a sealed, “tanked” area that directs water toward the central outlet, which connects directly to the plumbing system. Once tiling is complete, an adjustable spigot allows the grate to sit perfectly flush with the finished surface

Modern designs have improved installation efficiency. For example, Allproof’s Cyclone and Tilt-a-Grate flanges feature adjustable spigots for easy alignment, while the Revolver system incorporates a removable gully bucket, ideal for areas where cavity depth is restricted.

To complement the flange, a wide variety of grates are available. Stainless steel designs, such as Allproof’s Elegance, Wakatipu and Kaiteri series, combine durability with refined aesthetics, including lid-style grates that conceal waste outlets for a discreet and sophisticated finish.

Linear Shower Channels
Linear shower drains are increasingly popular in modern bathrooms, offering clean lines and efficient water management. Installed against a wall or at the threshold, they require a single-direction floor fall, reducing tile cuts and installation time.

Allproof’s Vision Series uses a rectangular puddle flange for dual-barrier protection against surface and subsurface water, while the SC Series incorporates the flange directly into the stainless steel channel for a fully tanked, integrated solution. Both systems support removable grates, including tile insert options that create a seamless appearance.

Vinyl Floor Puddle Flanges
Vinyl flooring integrates waterproofing and the finished surface into one continuous layer. The puddle flange is rebated into the substrate, with the vinyl membrane dressed into the flange and secured by a clamping ring to create a watertight seal. A cam-lock grate completes the installation.

While PVC flanges are commonly used, commercial settings often specify cast bronze for added durability and longevity. Grate finishes include chrome on brass, polished brass and stainless steel, allowing for both robust performance and an aesthetic match to the surrounding environment.

The Importance of Puddle Flanges
Whether for tiled or vinyl floors, puddle flanges are fundamental to maintaining building integrity by preventing leaks and meeting mandatory compliance standards. High-quality designs, such as those produced by Allproof, ensure long-term reliability, straightforward maintenance and compatibility with a variety of grate and channel systems.