We like doors,” says Ken Moeslein, CEO of Swing Line Windows/Legacy Remodeling, in Pittsburgh. “And a lot of our competitors hate doors.”

Roughly 75% of the storm and entry doors that Swing Line sells are add-ons to a window sale. That wasn't always the case. When the company first started carrying entry doors, its salesforce needed to be sold on them. Sales reps, Moeslein observes, often “turned up their noses” at a door lead, preferring their shot at a house full of windows. Then one salesman started selling $10,000 or $15,000 a month in entry doors, and everyone wanted to know how he did it.

BARRIERS TO ENTRY Apart from salesforce reluctance, other reasons why window companies shy away from entry doors include: the need for showroom space to display them, big-box competitors with low prices, and the challenge of finding installers.

Gary Arcieri, owner of Elegant Entries, in Deer Park, N.Y., a “door company that installs windows,” says his one-man door installation crews encounter numerous obstacles — rotten wood and the presence of electrical wiring, for example — that require carpentry skills more sophisticated than those needed to pop in a window.

Stanek Windows, in Cleveland, solved that problem by finding a crew that specialized in door installation, since crews that did both tended to give doors short shrift. “They're specialists, and it keeps it organized,” general manager Sven Kramer says.

HAND IN HAND For Stanek Windows, doors and windows go “hand in hand,” Kramer says. Customers who are “tightening up the house” with new windows can hardly ignore the door, or doors. Customer confidence and trust help to sell them. “Once the customer is sold on your company,” he points out, “other products are easy to sell.”

Dealers say that consumers buy entry doors for one (or all) of three reasons: aesthetics, energy savings, and increased security. At Swing Line Windows, the tie-in is to energy savings: You've just bought X number of triple-paned windows that will reduce heating bills by 35% or 40%. Now what about that old entry door, leaking heat through cracks?

For Arcieri, style is the biggest reason why consumers buy. “A lot of times salesmen will just sell the front door,” Arcieri says, “That's telling me [that the homeowner] is interested in style — or they would have bought the back door, too.” Security — a steel door set in a steel frame — comes in second.

Kramer says that many Stanek Windows customers buying doors are doing so for the simplest reason of all: Something is wrong with the door they have.