Can a person install a radiant heating/cooling system by themselves? How difficult is the installation process?

Have you ever considered installing a radiant heating or cooling system in your home but wondered if it’s feasible without professional help? In this guide, I will walk you through the process of installing such a system, detailing the challenges, the tools and materials you need, and the steps involved. By the end, you’ll have a better understanding of whether you can undertake this project yourself or if you need to seek professional assistance.

DIY Installation: My Experience

When renovating a new space, I decided to install a radiant heating system to ensure comfort and energy efficiency. Below, I’ll share the process I followed and how it turned out in my new renovation.

Installation Process

Below ground, I installed loops of 1/2 inch PEX above four inches of foam insulation using plastic staples intended for attaching PEX to foam. The PEX tubing lay beneath the rebar used to reinforce the 4-inch concrete pad poured for the floor. To create efficiency, I made four zones, each spiraling around the perimeter and winding to the center of the room before making a U-turn and following the path between the inward spiral back out to the source. The four loops joined at a pair of factory-made copper manifolds with ball valves, through which I did not add zone controls, opting instead to simply adjust the ball valves. One manifold could have incorporated thermostat-controlled zone valves.

Pump and Heat Exchanger Setup

The one-inch copper manifold was bushed down to 3/4 inch, and from there, 3/4 inch PEX tubing ran to a pump and a flat plate heat exchanger. The boiler produced a fluid ranging from 156 to 160 degrees Fahrenheit. I used antifreeze in both the boiler and the floor loops to ensure safety and prevent freezing. The boiler side of the heat exchanger had a tempering valve, keeping the fluid being passed to the floors around 110 degrees F. Two pumps—one on the boiler side and one on the floor side of the heat exchanger—were controlled by a single thermostat through a pump relay AR-822, designed specifically to control circulator pumps. The floor temperature was regulated to avoid being too hot, reaching about 90 degrees F on return. However, due to the design of the loop spirals, each square foot of floor received one warm flow moving toward the center and one cooler flow returning, ensuring even heat distribution.

Old Part of the House: Unfinished Cellar

In the old part of the house, within an unfinished cellar, I utilized a pile of aluminum plates, approximately the thickness of aluminum in a soup can, specifically designed for installing PEX radiant floor systems below a floor. These plates, about one foot by 15 inches, fit a U-shaped tunnel across the width that could be slipped over 1/2 inch PEX tubing. The 15-inch dimension allowed the plates to be stapled between joists on 16-inch centers with regular steel staples. The PEX tubing was supported by these plates and placed between the joists. Subsequently, 2-inch foil-backed foam was foamed between the joists to insulate the PEX and direct the heat up through the floor to the rooms above with minimal heat loss to the cellar. Ideally, the plates should cover one-third to one-half of the bottom surface of the floor above.

Old Floor Surface: Existing Materials and Adaptation

In our old house, the floor above was composed of one layer of 1/2-inch boards placed under the cracks between 3/4-inch boards, with hardwood floors above. The PEX tubing was attached to manifolds as in the new sections of the house. While the system has provided comfortable heating for over a decade, the original rooms in the old part of the house were heated with baseboard radiators. Though these are still in place and controlled by separate thermostats, they are rarely used due to the lower required temperature (at least 150 degrees Fahrenheit) needed for effective heating, necessitating no tempering valve.

Conclusion

Installing a radiant heating or cooling system can be a complex but rewarding project. Understanding the process, selecting the right materials, and following the steps outlined here can make it a feasible task for DIY enthusiasts. Before starting, consider the feasibility based on your home’s layout and existing structure. Consulting with a professional for a detailed assessment can also help ensure the system’s efficiency and safety. Installation can be challenging, but with proper planning, it can save you significant costs and provide a sustainable heating and cooling solution for your home.

Key Takeaways:

Radiant heating and cooling systems can be installed DIY if you follow specific steps and use the right tools and materials. The process involves detailed planning, including the plumbing, insulation, and heat exchanger arrangement. Ensure the system is energy-efficient and maintains a comfortable temperature through proper temperature control and design.

With these tips and insights, you’re better equipped to decide whether to tackle a radiant heating or cooling system installation yourself or seek professional help.