Step 3: Select the Right Type of Linear Drain System

Once the waterproofing method has been identified, the next step is to select the linear drain system best suited for the project.

In its most basic form, a linear drain system is comprised of the channel and the grate. The layout of the shower area and the waterproofing technique employed on the job determines the kind of linear drain channel that can be used on any given project. There are four basic types of linear drain systems: the fixed-length linear drain, the site-sizable linear drain, the fixed-flange linear drain, and a universal linear drain.

The desired aesthetic coupled with drain placement within the shower area will inform the selection of the decorative grate.

Fixed-Length Linear Drain

A fixed-length linear drain channel is constructed from one single piece of either PVC or stainless steel, depending upon the manufacturer. These fixed solutions also feature a predetermined outlet location, which is either positioned in the center of the channel or offset, and the channels are pre-pitched in the direction of that outlet.

A fixed-length linear drain does not allow for on-site flexibility. When the system arrives to the job site, the size of the drain channel cannot be modified, nor can the location of the outlet be changed. Due to its inherent lack of flexibility, the fixed-length linear drain solution may not be the best choice for a custom home or high-end renovation, but it is a perfect fit for projects that prioritize speedy installation, such as large multifamily or hospitality applications. Since barrier-free applications require a wall-to-wall application of the linear drain system, especially when the drain is placed along the threshold of the shower, custom fabrication may be necessary to achieve the dimension of the shower opening.

Site-Sizable Linear Drain

Site-sizable linear drains allow for more flexibility during installation because both the length of the channel and the location of the outlet can be modified on-site. In fact, the length of the channel can be cut on-site, and the outlet can be located anywhere on the channel run, offering installers the ability to accommodate construction tolerances that can occur during a job.

Site-sizable linear drains may be available in either a PVC or stainless-steel channel. Some local municipalities such as New York, Chicago, and San Francisco require all-metal plumbing components, so the stainless-steel site-sizable linear drain would be acceptable.

A site-sizable linear drain is a good fit for a project that will be installed with traditional waterproofing.

Fixed-Flange Linear Drain

In a flanged linear drain system, the channel shape is different than the channel used in a fixed-length or site-sizable drain. As the name may imply, the channel in this system features a 1-inch flange on all four sides.

This type of linear drain is necessary when modern waterproofing techniques are used. With this system, the liquid waterproofing is either painted onto the flange edge or the fabric is glued to the edge, making the shower watertight. The tile is then applied directly on top of the channel’s flanges.

While the fixed-flange solution is designed to accommodate more modern waterproofing methods, the channel does not offer on-site flexibility. The channel arrives in a fixed length and is pre-pitched toward the centrally located or offset outlet. Similar to a fixed-length linear drain, custom fabrication may be required to achieve a wall-to-wall installation that prohibits water from traveling to the dry side of the bathroom.

Universal Linear Drain

A universal linear drain features a pre-pitched channel with a set length and central outlet location. This type of linear drain system can be specified without knowing the waterproofing technique that will be used on the job: the system works with either a shower pan liner or with liquid/fabric bonded waterproofing methods. This type of linear drain is not compatible with lead pan, copper pan, or hot mop waterproofing applications. Again, this type of linear drain is a set length and may not be appropriate for a threshold installation.

Flush-to-wall installations describe projects where the linear drain is installed flush against the shower wall.