Q: Storm doors: Are they really necessary? — S. Starr, Larchmont.
A: This seemed like a question about energy efficiency, so I plunged into the web and found a site called ENERGYguide.com that began by informing us that “doors are necessary for access” — a point I think we can all agree on. That fact established, the site then offered more useful information, which suggested that good weather stripping and a tight seal are more to the point than a storm door. On the other hand, if you have an old, wooden door, ENERGYguide.com suggests that a storm may, in fact, help conserve energy.
Somewhat confused by R-values and door thicknesses, and not knowing what kind of door we’re discussing here, I called Frank Branca, general manager of New Dimensions Remodeling, Inc. in Mount Kisco. “The simple answer is that if you don’t have an overhang or roof above the existing door, then a storm door will give protection against snow, sleet, and driving rains,” Branca says. “If your door is exposed to weather, it will take a beating unless you have a storm door.”
If you do have a porch, or an overhang that measures at least four by four feet, your door is pretty well protected from the elements. As for the energy question, insulated fiberglass or steel doors are better at keeping the cold out than wood ones, but Branca says that most exterior doors these days are weather stripped and efficient no matter what they’re made of. If there are drafts coming through gaps in the frame, “then you have an older door that’s shrunk and you should replace it,” he says. A tight seal is what you’re after.
If you live in a house that predates thermal glass, man-made sealants, and other mod cons and your front door has a window, a storm door will cut down on heat loss. Or you could switch to a new door with a low-E glass windowpane. Many utility companies offer a free inspection to see where warm air is escaping. French doors and patio doors can leak heat, even those with thermal panes, but insulated draperies in winter may be an easier remedy than adding storms. “If you want a headache, put storms on French doors and see how aggravating that is,” Branca says.
Your question suggests that you’d prefer not to have storm doors—and Branca appears to agree that they’re inconvenient. “Going through two doors, it’s nothing but aggravation. You’re carrying bags, you open the door, you put the bag down to open the other door, it’s snowing, the bag’s getting wet…”
So, if an exterior door has a tight seal and is well protected from whatever Mother Nature is up to, the answer is no, a storm door isn’t necessary.