For most people, pampering in the bathroom means extras that enhance the senses. A feast for the eyes might include a luminous Carrara marble floor or a vanity that’s designed to look like a 17th-century, French baroque-styled dresser. Sore muscles and an aching back will find relief in the massaging power of multiple shower heads or the healing power of steam produced in an enclosed shower compartment.
But a perk that’s often overlooked will help you start every day from November to May on a high note — radiant heating under your bathroom floor. Instead of the jarring sensation of cold tile on your bare feet, you walk onto a warm floor that’s heated to about 80 degrees. As the heat spreads up through your torso, it gently nudges you into a new day.
Radiant-floor heating as an enhancement for a luxury bathroom is relatively new. Carolyn Thomas, a certified bathroom designer with Jennifer Gilmer Kitchen & Bath in Chevy Chase, said she turned to radiant-floor heating to address an ongoing issue with marble floors. Though visually stunning, marble and other natural stones are cold to the touch, and during the winter Thomas often saw homeowners cover large areas of their bathroom floor with throw rugs, especially when the space was over an unheated garage and poorly insulated. Despite the obvious benefits, radiant heating was not an easy sell initially.
In 2008, only about 20 percent of Thomas’s clients opted for it. But those early adapters raved about it to their friends, shelter magazines began to tout its virtues and now many more people want it, she said.
Radiant heat can also be installed under a shower floor and bench. Though seemingly unnecessary, the hot water of a shower does not heat all the floor area in the larger shower compartments that are common now, and Thomas said an unheated marble shower bench is “a mighty cold place to sit while you shave your legs.”
Characterized by heating specialists as “supplemental,” radiant-floor heat for a bathroom is intended to enhance the space, not to act as the primary heat source. In the Washington area, most of the systems are electrical, and, as with any type of radiant heating, they warm the space slowly, requiring at least 90 minutes to heat the floor to a comfortable 80 to 84 degrees from a standby temperature of 70. With a programmable thermostat that turns the system on while you’re still asleep, the floor will be “toasty warm” when you begin your morning routine; afterward, the thermostat can power the system down for the rest of the day.
How much does this luxury cost? It depends on the size of the bathroom and the actual area to be heated — you need it only in the places where you will be walking or standing; the area under the bathtub, vanities and the toilet can be excluded.
Paul Lappas, a remodeling contractor based in Bethesda, said the heated area for a master bathroom in a house that was built between 1930 and 1980 is about 30 to 40 square feet. A radiant heating system for a space of this size would cost about $1,200, which would include the programmable thermostat and installation of a new circuit by an electrician. After 1980, master bathrooms ballooned in size; the heated area for a radiant floor is nearly twice as big, and Lappas said his charge for installing a radiant heating system is about $2,400.
Kurt Welch, another remodeling contractor also based in Bethesda, said he often works on even larger bathrooms with radiant-heating floor areas in the 120-to-140-square-foot range. For these spaces, the cost of a radiant heating system runs about $2,500 to $3,000. Radiant heating for a shower floor and bench must be installed separately with different wiring; the cost for this, including a second thermostat, adds about $1,000, Welch said.
Radiant-floor heating for master bathrooms in new construction in the Washington area is offered only by high-end builders and not as yet a “must-have” option.
Toll Brothers offers radiant heating in its Estate and Executive Series homes in both Maryland and Virginia; for about 130 to 150 square feet of heated area in a master bathroom, the cost can range from $5,500 to $9,000. Up to 30 percent of buyers have opted for the feature.
Keswick Homes, the custom home division of Brookfield Homes, also offers this option; about half the buyers select it. Keswick’s master bathrooms are even larger than Toll Brothers’ with about 200 square feet of heated area. The charge for installing radiant heating under it ranges from $6,600 to $8,800.
Katherine Salant has an architecture degree from Harvard. A native Washingtonian, she grew up in Fairfax County and now lives in Ann Arbor, Mich. If you have questions or column ideas, she can be contacted at firstname.lastname@example.org or www.katherinesalant.com.