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Prefab 'In-law' Cottages Mix High-tech Features, Comfort

New freestanding modular home additions aim to provide the right kind of space for aging in place.

The ABCs of ADUs

Photo courtesy of FabCab

FabCab is a timber-frame kit home with universal design features. Click photo for more information

Eric Santolicito, 35, of Billerica, Mass., had a plan for looking after his parents as they grew older: The family man bought his sixtysomething parents’ home, demolished it and put up a new prefab house with an in-law suite on the lot.

“It was a win-win situation,” Santolicito says. “We cut our expenses for owning and maintaining two separate, older homes. Now we all have a new house with separate living quarters, and we stayed in the neighborhood where my sisters live, too. My parents were able to downsize a bit. They now have living, dining, bedroom, bath and kitchen spaces in about 800 square feet — much less for them to clean and maintain. I can look after all the yard work. And now we have the best on-site child care for our two little ones.

The ABCs of ADUs

Photo courtesy of MEDCottage

MEDCottage features options for advanced medical monitoring equipment. Click photo for more information.

See Also: Custom Prefab ADUs

“Building this house the way we did — it has alleviated a lot of stress for everyone in the family,” he says.

Not everyone is in a position to build a new home to support multigenerational families. But a number of manufactured housing producers are introducing new prefab home additions with features to support aging at home or near family members. Known in the building industry as ADUs (accessory dwelling units) and in consumer media as “granny pods” and “in-law apartments,” the new self-contained units incorporate barrier-free, universal designs and options that include electronic monitoring and medical care equipment.

All are largely built or prepared for assembly in a factory, trucked to a building site and set on a foundation, which manufacturers claim cuts construction costs and time from initiation to occupancy.

FabCab, a Seattle-based manufacturer of timber-frame kit homes, offers ADUs ranging in size from 300 to 1,800 square feet. A Salem, Va., startup called N2Care will begin manufacturing the MEDCottage — a portable ADU for temporary or extended care at home with options for high-tech medical monitoring and security equipment — in January 2011. And The Home Store — a long-established manufacturer of high-end modular homes in the Northeast — is now offering freestanding, custom-designed “in-law” units.

Are ADUs a Good Solution?

“From many angles, the ADU concept is a sound one,” says Susan M. Duncan of the National Resource Center on Supportive Housing and Home Modification at the Ethel Percy Andrus Gerontology Center at University of Southern California. “An ADU occupies the same space as an apartment but makes it into a private, freestanding home. Privacy is something we all strive for. And families are happier because the TV can be as loud as you want without disturbing the grandkids doing homework,”

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Jane Marie O'Connor, of 55 Plus, LLC, in Charlemont, Mass., a building industry consultant, sees at least a potential pitfall in ADUs for those in need of care: “One key element that can still be missing would be human contact. Living in or near the home of an adult child who is likely gone all day provides little or no stimulation if there is no opportunity for socialization, which many assisted-living facilities are good at providing.”

O’Connor believes that ADUs can be a viable alternative, “but not without consideration. Make the choice with thoughtful purpose, and don’t plan to just park somebody there. Plan how to help her stay engaged in the wider community.

“And don’t forget that at-home health care always takes a toll on the caregiver. Again, plan ahead for support and relief from care duties,” O’Connor says.

ADU Costs vs. Conventional Additions

Are ADUs less expensive than comparable home additions built in the conventional way? If you’re able to put an ADU on your property, the answer is probably yes.

Since prefab additions are relatively new, cost data for direct comparison with conventional home additions aren’t available. Instead, we have to work with comparisons between new prefab and homes  built on site. The consensus among cost estimators is that prefab costs less than stick. How much less?  — an online building cost reference tool — says that “modular construction costs 5 to 25 percent less than traditional homes built on site.”

Construction costs vary widely by region and local market conditions. Remodeling is generally more expensive on a square-foot basis than new

construction because contractors must price-in unknowns they may encounter in modifying or building on to an existing structure. Installing an ADU is more like new construction than remodeling. Therefore, savings for a freestanding modular ADU could be much greater compared with a conventional home addition of comparable size that includes a kitchen and bath — high-ticket items in home construction calculations.

The Potential Value of ADUs

One position in the cost versus value argument for ADUs holds that the total cost of installation — plus whatever you may need to spend for home health care professionals to look after sick or disabled relatives — might well be lower than costs for assisted-living or nursing home care, which generally run from $5,000 to $7,000 a month for an individual. There’s a corollary to the total cost argument for ADUs: While you can’t recoup money spent on assisted living or nursing home care, that’s not always the case with an ADU. When you don’t need the space for care, it can be repurposed as a home office, studio, rental unit, guest space or nanny quarters.

Corinne Fitzgerald of Fitzgerald Real Estate in Greenfield, Mass., and vice president of the Massachusetts Association of Realtors, agrees, but with caveats. “As long as zoning regulations allow and the space can be used for another purpose later, an ‘in-law addition’ is a good investment for families looking for a place to accommodate extended family, such as returning kids or parents.”

What is the marketability of an ADU down the road? According to Fitzgerald, how much of the initial costs you can recoup will depend on the real estate market in your area and how elaborate the addition or dwelling is.

“Don’t overimprove,” she advises. “And it’s absolutely critical to check local zoning regulations to be sure that if you are counting on using the space for a particular purpose later, that use is allowed.” She also recommends that you meet with a local Realtor to be sure that a planned addition won’t price your home out of the neighborhood. And before settling on an ADU or any addition, do your homework by looking at the cost of renting a separate space nearby for extended family compared with adding space at home.

Finally, Fitzgerald cautions, the dollar amount may not be the best deciding factor. “There’s much to consider besides the bottom line, including the quality of care for a loved one, travel time and the cost and wear and tear on the caregiver, not to mention your own peace of mind.”