How to Set Up PEX Radiant Heat for Floor Heating

What You'll Need
PEX Tubing
PEX Manifold
PEX clamps
Subfloor Materials of Choice
Hand tools

One of the most popular heating options in new construction as well as remodels is the PEX radiant heat. This heating method runs water through "pex" tubing that is installed in the flooring of the room or home. The water is heated to a temperature that radiates heat throughout the room, while staying safely enclosed PEX tubing in the subfloor. PEX tubing has been around since the '60s, but wasn't widely used or highly regarded until recently. It is currently being used in all kinds of plumbing applications, particularly to route hot or cold water to various fixtures throughout the home or building. It is almost exclusively used for radiant floor heating, as it will last decades, and is extremely efficient. Here you will find the information needed to set up PEX for radiant floor heating.

Step 1 - Determine the Amount of Tubing Needed

First you will want to make sure that you have enough tubing for your project. First, determine the layout of the tubing. Generally, the tubing can be arranged in a variety of different configurations, but it is almost always laid out in rows or loops sixteen inches apart. Measure the length and width of the room or area that you will be adding the radiant heat to, Use these measurements to determine the amount of the PEX piping that you will need.

Step 2 - Selecting a Manifold

One of the most important parts of the radiant floor heating system is the manifold. The manifold will allow you to turn certain areas of the heating off and on. If you create several different "zones" for the radiant floor heat, you will have greater control over the heat that is produced in the room. Select a manifold that will support the number of zones that you will have planned for, plus a couple of extra. Once you start planning and realize the benefit of different zones, you will likely discover that you will need more than you thought.The PEX will ultimately be connected to the manifold, which controls the flow of hot water to the heating system.

Step 3 - Choose a Subfloor

Selecting a subfloor can be a bit of a challenge. If you do not already have PEX installed in your concrete slab, it can be a daunting process to consider adding it. If you are building a new construction home, you should add the PEX to a concrete slab for use in the future, even if you do not have plans to currently heat the area. At least it will be an option to utilize in the future if you should change your mind. If this is a remodel, there is a particular type of subfloor product that is specifically designed to work with PEX radiant floor systems. This is a gypsum subfloor product that has pre-fabricated grooves in it so that you can easily lay the PEX, then install the final flooring on top.