For the Niles family a home elevator was a necessity. It meant they could remain in their house in Woodbridge, Va., and allow a child with a neuromuscular disorder to independently negotiate all three levels.

But when the elevator was installed, other uses surfaced. “Now that we have it, we started to realize our visiting parents with aging knees can get to the bedroom without climbing the stairs,” said Cheryl Niles. And when cargo needs to move between floors, like the recent artificial Christmas tree, bins of decorations and spools of lights, she added, “my husband and I use it as a giant dumbwaiter. I think we moved it all by sending the elevator up three times.”

It also means the Niles’s house is prepared for the day when the aging knees of Cheryl and husband Sean become an issue. “We have made it so my husband and I can stay here as long as we want to,” she said.

Thanks largely to an aging population that wants to remain in their own homes rather than move to a retirement community, residential elevators are becoming commonplace. “I don’t have a formal report, but I would say we have seen about 10 percent growth every single year over the past three years,” said Katrina Maheu, marketing director for Savaria, which claims to be the largest lift manufacturer in North America.

Vince Butler, a Clifton, Va., remodeler with a specialty in aging-in-place construction, said he has seen the demand for home elevators evolve over 25 years. “It went from a necessity item people were almost embarrassed to have to a luxury item that only wealthy people had.” Now, he said, it’s a common request by over-40 remodeling clients.

Home elevators may be more common, but reliable sellers and installers aren’t.

Regulation and oversight are spotty, experts say, so buying a serviceable and safe elevator requires some due diligence. But there are steps you can take to help protect yourself from fly-by-night manufacturers and sketchy installers, which is crucial to safety. Especially if you have children — your own or those of visitors — who are particularly susceptible to life-threatening injury from deficient home lifts.

“In the residential elevator sector there are few state inspection departments enforcing turnover and annual inspections, and to me that’s a problem,” said John Koshak, a forensic consultant and expert witness at Elevator Safety Solutions. “By far the highest number of incidents are in the residential installations.”

There are a wide variety of elevators available, from $20,000 closet-like boxes that move floor to floor to all-glass models with automatic doors and advanced safety features that can run six figures.

The cost of the elevator itself is a relatively small part of the expense of putting one in, however. To install a shaft and sometimes a mechanical room is a larger undertaking. “If it’s an existing house and we have to go in with a whole elevator it’s in the $50,000 to $70,000 range, and $20,000 of that is the elevator,” Butler said. The additional cost comes from modifications commonly required to reroute heating and cooling systems, and by adjustments to the foundation and roof. “It’s a challenging job to do,” he added.

For that reason, and because the elevator shaft may reduce space inside the house and generally mess with the flow, “usually the elevator is part of a larger project,” said Ellen Hatton, an architect with BarnesVanze Architects in the District, which sees “a fair amount of demand” for elevators.

Even people who aren’t ready for an elevator now often plan for one as a part of an addition or new construction, she said. In those cases they build a shaft, but floor in each level for use as storage. “We will cut in the shaft with closets stacked floor to floor, then the builder can come in and install the elevator later,” Hatton said.

In some cases a bump-out can be put on the side of a house for the shaft, but homeowner associations may have something to say about it. In the case of the Niles family, the shaft was added to the outside but was approved because they matched the facade so it blended with the existing structure.

The other potentially large expense is fitting out the elevator cab. “Do they want it bare bones, or we’ve done some with etched glassed panels, different wood species — it can become fairly involved,” said Michael Menn an architect, builder and aging-in-place specialist headquartered in Northbrook, Ill.

For the Nileses, the idea was to make the elevator look as if it had always been in the house. To visitors, it appears as a door at the end of a hall, no different from any other. “Most people who come into our home don’t realize there is an elevator there,” Cheryl Niles said. The interior is finished to look like an extension of the hallway that leads to it.

Homeowners too often give short shrift to safety because they are unaware of the risks, experts say.

A Washington Post article last year reported that an unknown number of child deaths have occurred because small children can fit in the gap between the exterior door and the interior door of the elevator cab. They could be crushed by the elevator moving in either direction.

The article said that the industry opposes safety regulations even though there is a simple solution to the threat of crushing. Regulators at the Consumer Product Safety Commission have failed to take aggressive action on behalf of consumers.

The danger is easily avoided by adding a $200 barrier, sometimes called a space guard, to the inside of the outer door, said Robert Shepherd, executive director of the National Association of Elevator Safety Authorities. “The space guards work.”

Ron Rucker, president of the Accessibility Equipment Manufacturers of America and of Neoteric Elevator Concepts, did not respond to several emails, nor did any residential elevator sales organization contacted for this article.

The full extent of the danger is hidden, said consultant Koshak, because, as with many liability lawsuits, “the secrets are sealed,” he said.

Safety begins with the choice of an installer. “We strongly advise against picking the equipment or the manufacturer before finding the right contractor,” Cheryl Niles said. “This was one of our biggest mistakes.”

She said the contractors recommended by the lift companies were solely focused on the mechanics of the installation. “They had no interest in how it would affect the flow and layout of our house,” she said. “You could kind of think of it as not hiring your favorite plumber before you find a general contractor for your bathroom remodel.”

Hiring an architect or contractor with experience in aging-in-place projects is probably a good starting point. They should both know about elevators and be more attuned to design. One place to find them is through the National Home Builders Association Certified Aging-in-Place Specialist directory.

If you prefer to use a specialist installer instead of an architect or builder, don’t get references only from homeowners. “I would ask what builders are you installing these for,” Butler said. “Builders tend to be more critical of their trades and installers than a homeowner.” You also want someone with at least five years of experience, and who is a member of an industry group that provides training such as the Accessibility Equipment Manufacturers Association.

Although there are different elevator mechanisms — hydraulic, chain driven, counterweighted and so forth — there is little point in debating the merits of each because your home layout will dictate the sort of elevator that is possible to install. “You don’t choose the elevator, the elevator chooses the customer,” Butler said. “The mechanical space is the driving force.”

Don’t scrimp on basic safety features. “Always get an elevator with an automatic door,” said Koshak, which prevents potential child entrapment. And in many cases the space filler is still worth it, he said.

Whether an inspector is required or not, hire one. “Not all installers are motivated by safety,” Koshak said. “They are motivated to get in, get out, get paid.”

When you buy, get an elevator made for the Massachusetts market. The state has a high safety standard, which requires special doors on those elevators, Koshak said. It will come with mechanical drawings that show installers how to achieve a minimal gap between the inner and outer doors.

Safer operation may cost a bit more, but as much as adults need elevators, kids are fascinated by them. “The kids in the neighborhood like it,” Cheryl Niles said. “There is one little girl who likes to ride it. She just comes over and rides.”

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