Installing Radiant Floor Heating: Everything You Need to Know

Radiant floor systems are composed of various components, both small and large. In this post, we’ll explore the essential equipment required, the installation process, and the best flooring types for radiant heating systems. Let’s dive in!

What Equipment is Required for Radiant Floor Heating?

1. The Boiler

Selecting the right boiler is crucial. Conventional boilers operate at higher temperatures, reducing efficiency and requiring protective measures. Modern boilers, however, are engineered for lower water temperatures, enhancing energy savings and comfort. They adjust the water temperature based on outdoor sensors, effectively operating on “cruise control.”

2. Boiler Components

Several small components work with the boiler and floor loops, including:

• Circulator Pumps: Force hot water through the plumbing system.
• Expansion Tank: Absorbs the initial pressure increase when the boiler heats up.
• Pressure Relief Valves: Prevent boiler explosions by releasing pressure if other controls fail.
• Air Elimination Components: Capture and remove air from the hot water piping.
• Dirt Separator: Collects and removes dirt particles from the system.
• Mixing Valves: Temper outgoing domestic hot water or control floor heat temperature.
• Service Valves: Allow system servicing without a complete shutdown.
• Zone Valve and Controllers: Manage hot water circulation through multiple heating zones.

3. Tubing

We use PEX tubing for slab or thin-slab applications and Watts Radiant’s Onix tubing for complex bends. Onix is versatile, does not require additional accessories, and is quiet due to its stability under temperature changes.

4. Manifolds

Manifolds distribute water through the system and are central to radiant, snow-melting, and hydronic applications. They include individual shut-off valves for specific areas without affecting others.

5. Controls

Standard forced air heating thermostats aren’t suitable for radiant floor systems. We prefer Tekmar radiant thermostats, which use Pulse Width Modulation and Indoor Temperature Feedback technology to maintain a steady floor temperature. They also offer options for floor temperature sensors to protect hardwood floors and maintain comfort in rooms with large windows.

How to Install Radiant Floor Heating

Radiant heating systems can be installed using wet or dry construction methods and are compatible with various floor coverings, including hardwood, carpet, vinyl, ceramic tile, and natural stone. Here’s a breakdown of each method:

Wet Construction Methods

• Concrete Slab: Lay a radiant insulation panel on a gravel base, route the tubing, and pour concrete over it. Suitable for basements, garages, or snow and ice melt systems.
• Over Pour: Lay tubing on a subfloor, secure it, and pour lightweight concrete over it. Ensure insulation underneath the tubing to direct heat upwards. Ideal for floors above basements or thick concrete slabs.

Dry Construction Methods

• Below Subfloor Staple Up: Fasten radiant tubing to the subfloor’s underside with clips, with insulation below to direct heat.
• Below Subfloor Panels: Install pipes in joist spaces under a suspended wood floor, using heat transfer plates to increase efficiency.
• Above Subfloor Panels: Install pipes in grooved conductive panels on the subfloor. These systems offer faster response times compared to wet systems.

By understanding the necessary equipment and installation methods, you can ensure your radiant floor heating system performs optimally and enhances your home’s comfort.