A.Kevin Stack, a certified home energy rater in Syracuse, N.Y., responds: The traditional open-hearth fireplace has a lot of charm and is often at the top of the typical new-home buyer's wish list; it is also inefficient, creates a break in the thermal envelope, and generates both indoor and outdoor air pollution.

For these reasons, the energy codes in many states — including New York's Energy Conservation Construction Code (102.7) — require that solid-fuel fireplaces be installed with tightfitting noncombustible fireplace doors to control infiltration losses. New York's building code also requires factory-built and masonry fireplaces to be equipped with an exterior air supply to assure proper fuel combustion, unless the room is mechanically ventilated and controlled so the indoor pressure is neutral or positive.

Unfortunately, these requirements can be both expensive and difficult to implement — while providing limited benefits.

Still, here in the Northeast, I've found that the aesthetic value of a masonry fireplace is strong enough for many buyers to be willing to overlook these concerns. So when homeowners want a conventional fireplace, my first recommendation is that we mimic a traditional-style hearth but install an EPA-certified fireplace insert. If they demand the real thing, we build them a Rumford with tightfitting glass doors, provide the required makeup air, and advise them of the problems and limitations they may encounter.