A radiant hot water heating system was installed under a new concrete floor slab above the old foundation. It was coated with epoxy — light gray for the common areas, white for the bedrooms and bathrooms — then finished with matte polyurethane.

Thanks to passive solar and radiant floors, the metal-clad home is comfortable year-round.

The radiant-heating system's pipes and gauges hide in a closet.

Perhaps the greatest challenge of the project was trying to pack so many energy efficient features in under a budget. Not only does the bathroom feature NuHeat radiant floor mats but all water is heated with a GE Hybrid Heat Pump Water Heater, saving on heating expenses by around 67%.

A Woolly Pocket planter hangs on the steel beam above a polished-concrete floor warmed by radiant heat.

In the winter, radiant heating keeps the house cozy while reducing the costs and the pollutants associated with traditional forced air.

The Airstream's height and length were extended for comfort and ease, and an HVAC system was installed with hydronic and radiant floor heating.

The red wall cabinet was designed by August. The floors throughout the home were replaced with wide, salvaged heart pine floorboards with radiant heat.

ANACAPA Architecture designed Minimalist Urban Residence with California's temperate climate in mind. Radiant heat cement floors that extend into the study keep the home warm on cooler days.

The pour moves on to the living room where the red PEX radiant heat tubing is evident.

Pouring the garage floor. There is no radiant heating in the garage and so none of the red PEX tubing here.

Ceramic floors with radiant heating and cozy wall sconces top off the distinctive appearance, smell, and sound.

The corrugated steel siding and roof reflect the radiant heat from the desert sun.

MicromanagementA Weil-McLain gas-fired boiler and underfloor radiant heating keep the house comfortable year-round—as do the individual programmable thermostats installed in almost every room, seven in all. That means the couple can lower the heat in rooms they use less frequently while keeping things toasty in the places they spend the most time. It’s a smart way to maximize energy efficiency through Alaska’s disparate seasons. weil-mclain.com

The bathroom floor is grey porcelain, equipped with radiant heating. A cedar wall adds a different kind of warmth to the space.

Rian and Melissa Jorgensen's 2 Bar House in Menlo Park boasts all the usual green design suspects: energy-efficient lighting, good insulation, renewable material finishes, radiant heat, and the roof is pre-wired for future PV panels. Still, one of the homeowner's favorite aspect of green design is the living roof planted with succulents, aloe, viviums, and ice plants.

Walnut ply millwork by Ashley Woodturning and polished concrete floors with radiant heating appear throughout the residence.

The main living area is open and fluid. The polished concrete floors have radiant heating.

To the architects’ surprise, the original radiant heated floors that were run by a single-zone system were still working throughout the year they lived in the house prior to the renovation. However, since they were more than 60 years old, Jay and Melissa abandoned the old system and installed a new radiant heating system with thermal mass polished concrete floors.

The renovated cottage is light and airy. The flooring is re-milled oak barn siding. The house is heated with a hydronic radiant system.

The bathroom features radiant heating to keep you warm on the cooler winter days.

Interiors include an open floor plan, high ceilings, radiant heat, and hardwood floors throughout.

Radiant floor heating, a high-efficiency boiler, a heat recovery ventilator, and a convection wood stove work to conserve energy.

Each bathroom in Huys is decked out in Chambolle stone slab, from flooring to countertop to wall tiles. Piet Boon-designed lighting illuminates a Duravit sink, Dornbracht fixtures in matte platinum, and a Kaldewei soaking tub. The floors are equipped with radiant heating by NuHeat.

The home features silent and cozy radiant floor heating—a very forward-thinking feature—and there is not a single heating vent or visible outlet in sight.

The metallic skin and white surfaces amplify the home’s radiant golden glow—even at night.

Reclaimed Douglas fir lines the 11-foot-tall ceilings, while stone-tiled floors with built-in radiant heating are located underfoot.

Listing agent Sherri Kielland explains that in order to preserve the radiant heated floor, she chiseled the original floor off while cataloging all the stones. After laying down the new radiant heated bluestone floors, she pieced it back together like a puzzle. She also dug a well under the kitchen area to house the mechanicals of the house.

The living room couch is from Élément de base. Radiant heating is built into the polished concrete floors (Atelier B).

“The sun rises behind the house and heats up the concrete mass during the morning, and [comes] through the front of the house in the afternoon; if need be the radiant energy warms up the house when temperatures drop in the evening,” says Thorsteinsson. Thanks to the thoughtful process, the couple was able to leave out the air-conditioning, and the house’s under-floor radiant heating system has turned out to be almost superfluous.

Polished concrete floors with integrated radiant heating are used throughout the home, while the walls are lined with white-painted wood planks.

In addition to a radiant floor heating system, a Cheminees Philippe Radiante fireplace keeps the home toasty and warm. The artwork pictured is ‘Commonalities’ by Kate Tucker.

Large vintage pendants from an old ship suspend above the dining table, crafted by Dave Ball of Jacob May in Oakland. The radiant-heat flooring is reclaimed barn wood from Tennessee. The artwork that hangs above the cabinet and conceals a television was created from pieces of wood painted by local artists during a party hosted by Marka and Joe, who elected to leave the living area's large metal structural beam exposed.

Lynch installed a radiant heated system, passive solar elements, and a gas system that’s backed up by forced air.

Inside, the flooring is radiant concrete, and the home is further warmed with a clean-burning Flores 8 stove by Buntfires. In fact, the entire house is conditioned without the use of fossil fuels.