QUESTION: Our old front door looks bad and we can feel a draft near it on windy days. We need to install a new, more efficient one. We like the look and security of steel doors, but doesn't the metal waste heat?ANSWER: I have installed and tested every type (steel, wood, fiberglass, and carbon fiber) of front door in my own home and my preference is clearly an insulated steel door. I particularly liked the clean appearance, the airtight seals and the added security steel offers.Even though steel does conduct heat, insulated steel doors are one of the most efficient of all designs. The steel skins are thin and there is an insulating thermal break between the indoor and outdoor skins to block the direct flow of heat. The interior of the door is completely filled with insulating foam.Another significant advantage of a steel door is it is magnetic. This allows refrigerator-door-type magnetic weatherstripping to be used on the frame.When the door closes, the seals snap tightly to the door.One of the primary factors indicating quality and strength of a steel door is the thickness of the steel skins. Sheet steel thickness is designated by its gauge rating.When comparing steel doors, keep in mind a lower (24-gauge vs. 26-gauge) number indicates a thicker steel skin. You should be able to find this specification shown somewhere in their sales brochures.I would recommend installing a prehung steel door that includes the door frame and hinges. The frame will be made properly for an airtight seal with the door.The following companies offer steel entry doors: Jeld-Wen, (800) 535-3936, www.jeldwen.com; Pella, (800) 883-6677, www.pella.com; Taylor Door, (800) 248-3600, www.taylordoor.com; Therma-Tru, (800) 537-5322, www.thermatru.com; and Weathershield, (800) 222-2995, www.weathershield.com.Send inquiries to James Dulley, Butler Eagle, 6906 Royalgreen Dr., Cincinnati, OH 45244 or visit www.dulley.com

QUESTION: I just bought an older home that has an oil furnace. It still works, but I think a new one would be more efficient. We have gas available, so should I get a new oil one and should I switch to gas from oil?ANSWER: The energy market is very unstable now and it is difficult to predict its future. Both oil and gas are in short supply. Since the existing oil furnace in your home is still working, wait to replace it until the energy markets settle down. At that point, your contractor can make better long-term payback estimates.James Dulley has a degree in mechanical engineering. His Sensible Home column appears in 400 newspapers.