Rhode Island firm 3six0 has converted the garage of a family home to make room for an in-law residence adjacent to the main house (+ slideshow).

The architects had previously renovated the residence in 2011, so were familiar with the family's needs and the project's site.

An existing garage and tool shed were converted to house the extension, which was created for the one of the client's elderly parents. The single-storey volume was previously connected to the main house.

Further west, a new garage was built, freeing up the front yard by diverting the driveway away from the main residence.

The result is a volume that branches off the house and is made up of three distinct massing elements.

"The wing is broken into three related yet distinct program masses – garage/tool shed, in-law residence, and home office," said 3six0.

The architects aimed to establish a visual continuity between the existing house and new elements.

"Western red cedar linking elements bridge the gaps between the different masses and relate to the vocabulary of the main house," they explained.

Between the new garage and in-law residence, a cedar wall creates a covered porch that allows residents to access both spaces.

The entrance leads into an open-plan living room and kitchen. This space is illuminated by a large southern-facing window.

"The location of the structure offered wonderful unobstructed views across the landscaped yard and down to the Pettaquamscutt River," said the studio.

The window is framed by red cedar elements that create an overhang. This prevents overheating during the summer months, yet allows sunlight into the home during the winter.

A modest bedroom is located in the eastern portion of the extension.

Given the residents' age, the entire addition complies with wheelchair accessibility standards. "The living spaces are ADA accessible, with no steps and rooms that are connected with wide pocket doors that are left open most of the time," said the firm.

A clean material palette was chosen on the inside, with wooden floors and white surfaces throughout. The north wall of the living rooms features floor-to-ceiling maple shelving that houses the residents' memorabilia.

"The interior was designed with simplicity in mind, for the homeowner's parents to enjoy the rest of their years," said the architects. "The space will also eventually be converted to a guest residence for visiting friends."

Other facilities designed for elderly tenants include a cluster of white cubes in Portugal that turn red in case of emergency and a monochrome gabled structure in Paris.

Photography is by Bob O'Connor.