What is a Flange on a Shower Drain?

The term flange is often misused when it pertains to the shower pan industry. In this blog we will set the wording and application or What is a flange on a shower drain?

The Actual Definition of a Flange

The flange is a type of connector that is used to connect different types of parts in plumbing systems. In the shower pan world it is often used to describe the drain itself, which leads to some confusion. So here goes a bit of clarity to what the pieces of the drain are.

Pieces of the Drain

The drain as a whole is called the drain body. It may consist of as little as two pieces and up to four or more! What the pieces are called varies with who you ask even in the plumbing field! The definitions I will give get your point across and let you know if what you are purchasing will met your requirements for the project at hand.

• The drain and all its pieces can be referenced as the Drain Body
• The bottom part of the body which attaches to your drain line and P-trap can be referenced as the Bottom Flange
• The second part which needs to be bolted to your Bottom Flange can be referenced as the Top Flange and it serves as the Clamping Ring because it has a positive connection, via the bolts, to the Bottom Flange that can sandwich the layer(s) of the membranes between the two. This sandwich effect is required by code in almost all shower pan applications
•  The finish screen is what you see when your shower has been finished, it can be a simple round, square screen, linear style with grate or other insert material. There are many choices and styles to choose from, but it all starts with choosing the proper drain body to achive the results you are looking for!

Drain Installation

Now that we have the information we need on the parts of the drain body, a brief overview on the proper installation. (See our video for a more detailed presentation)

• The drain bodies bottom flange should be set in place directly on the sub floor and securely held in place by straps in the case of wood subfloor or encased a minimum of 2 inches concrete when filling the plumbing box on slab.
• Make sure the top flange is level.
• Some drain styles have screw holes that can be used to secure the drain to the subfloor

Although just a small part in your overall project the drain choice and style correctly picked for your needs is something that needs attention, all the small things done to your needs gives the final project the satisfaction of a project well executed!

Not all installations are the same and remodeling your bathroom may bring on special circumstances that may limit the style of drain you can use. Drain placement, curb height desired, size of shower, and a few other factors will come into play. Getting your requirements to your contractor and gathering your options from start to finish will help make your shower install the way you want it.