4 Questions You Need To Answer Before Buying A Roof Drain


Like most industrial products, over time, roof drains can break down. Cracks, breaks, rust and corrosion are all culprits that can eventually lead to leaks.

Whether you’re in the market for a replacement drain, or you need multiple for a new project, here’s a list of what to consider before making a purchase.

1. What Make and Model Do you Need?

Zurn roof Drains

There are a number of different drain manufacturers, each offering quality products. If you’re working on a new building and are uncertain of which commercial drain brand to use, contact our expert who can walk you through which product is best for your roof’s design and material.

If you are replacing a drain, but don’t know which manufacturer or model to buy? Ask our Drain Wizard. It will ask you a series of questions (including some related to step 2) and locate your drain based on your answers. You can then purchase the product online and typically have it shipped within 24 hours. 

2. What Are Your Drain Dimensions?

How to measure a roof drainDifferent drain models come in different sizes, each primarily determined by how much water needs to flow through it. There are specific size aspects of a roof drain that need to be defined before purchasing.

The following videos will teach you exactly how to get the dimensions you need:

3. What Are Your Options? 

Flat Roof Drain Options

Most drains come with a variety of options to ensure they work for the roof material and design. Make sure to list out any drain options that may vary from the standard drain. For example, below are some of the options offered by Zurn:

4. What Are Your Outlet Requirements? 

In order to create a tight seal with the plumbing, the drain will also need the correct outlet type.

Determine if you need:

  • Inside Caulk (IC) – Often specified where the drain body is positioned on the pipe. The bottom of the outlet is sealed with oakum and the connection is then completed according to local plumbing codes.
  • Threaded (IP) – The iron pipe threaded connection is an old industry standard. The female (NPT) threaded outlet is often specified on industrial and institutional applications.
  • No-Hub (NH) – This is the most widely used connection. A no-hub connection is achieved by butting no-hub soil pipe, or plastic pipe, to the bottom of drain, and securing it with a NH joint clamp.
  • Neo-Loc (NL) – A unique labor saving compression gasketed connection designed to simply push on the stub end of the pipe. The neo-loc drain body and gasket can be utilized with plastic, steel, no-hub and service weight soil pipe. 

Once you’ve answered these questions you can have confidence selecting the right roof drain. If you need more detailed information and help with selecting a roof drain, contact our trusted advisors at 800-635-0384.