Comfortable, efficient heating for residential and commercial spaces. Don't fear the cold floors anymore.
What do people love about radiant heating?
- Radiant, sometimes called under-floor, heating is a way to heat a building by circulating warm water through a network of RAUPEX® piping, typically embedded in concrete.
- The warm surfaces radiate to the objects and people in the space, creating a comfortable environment.
- You don't need to step out of the shower on to a freezing tile or sit in a different part of the office to avoid a forced-air draft anymore!
The Milwaukee Art Museum showcases fine art and an unseen masterpiece in radiant heating design.
If a thermostat reads 70°F (21°C), will everyone in the room be comfortable? Probably not. The temperature of the surfaces around you, air speed coming out of your vents, humidity and air temperature are factors that your heating or cooling systems can address. Your clothing and metabolic rate also contribute to your comfort. Together, these are the six primary factors that influence human comfort. With radiant, you can control more human comfort variables. Specifically, you can adjust the actual surface temperatures of the objects in a space by emitting heat through a network of PEX pipes hidden in the floors, ceilings or walls. By changing the temperature of the surfaces around you, less of your comfort depends on the temperature and velocity of the air in a room.
Save ~30% on your heating bills with well-designed radiant systems.
Do you like your bedroom a different temperature than your bathroom? With radiant, you can create many zones in your building. That means you could maintain a warm floor in a bathroom, while keeping the adjacent bedroom cooler.
Flexibility in architectural design
Architects love radiant, because you can reduce the HVAC clutter in a space. Architect Frank Lloyd Wright even used radiant in his iconic Fallingwater House. Radiant heating is often used for floors, but can also be installed in walls and ceilings.
Low supply water operating temperatures and large surface areas are key for reducing fuel consumption. In best cases, the water for a radiant system is warmed by energy-efficient, condensing boilers or renewable energy sources.
How it works
Heat emission from the human body occurs mainly via four mechanisms: radiation, evaporation, conduction and convection. Humans feel most comfortable when they can regulate at least 50% of their heat emission via radiation.
As an example, you feel warm when you stand in direct sunlight, even on a cold day. While the air temperature may be cold, the warm radiation from the sun feels nice. With radiant heating, the entire floor of your home can be a warm heat source, radiating heat to warm your skin. As an added bonus, all of the objects on the floor warm up, so no more ice cold chairs.
Human comfort is a complex topic. Experts at ASHRAE have developed a building standard focused on human occupancy. Robert Bean, host of healthyheating.com also has great explanations for how all of the complexities of comfort work together.
Radiant distribution piping & connections
Whether you are a residential contractor needing to distribute hot water to radiant manifolds or baseboards, or a commercial contractor needing to distribute hot water to a snow melt system or cooled water to a chilled beam system, anywhere you're using hydronics, PEX pipe can be the distribution method.
REHAU account manager Donna VanMeter explains why PEX is a highly workable, robust and quick-to-install piping system in an article for PHCP Pros.
While forced-air is essential for ventilation and humidity control, it makes sense to cover more of the building’s sensible heating load with radiant. Water carries 3,500x more heat energy than air. HVAC designs that use a hybrid radiant and downsized/optimized forced-air system are an excellent way to address high-performance buildings, without sacrificing occupant comfort. Radiant excels in large commercial spaces, with high ceilings. Warehouses, hangars, schools, offices and zero energy targeting buildings are great fits for radiant.
Learn more about radiant
How does radiant make it in to so many zero energy buildings? Watch this 8-minute online seminar for more radiant background, energy efficiency and comfort topics.
Radiant heating articles in publication:
- What Hydronics Contractors Can Learn From Plumbing Contractors PHCP Pros 05.2021
- Growing Demand for Warehouses is Fertile Ground for Radiant Heating Radiant Comfort Report 05.21
- Collaborative planning enables tight radiant heating/cooling installation timeline at university Plumber 01.20
- Radiant: More than just a luxury home building option Plumbing and Mechanical, 11.19
- VAV vs Radiant: Side-by-Side Comparison ASHRAE Journal 05.14
- Radiant Design for Performance IE3 05.14
- The Path to Near Net-zero is Underfoot HPAC 02.14
- REHAU Radiant Heating and Cooling Systems Deliver on Energy Efficient Goals PM Engineer 01.14
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