GROTON -- As it celebrates 20 years in business, Platt Builders, 31 Adams Ave., has been awarded two national awards for superior craftsmanship.

The 2013 Chrysalis Awards for Remodeling Excellence recognize the nation's best work in 16 categories of residential and commercial remodeling. Platt took home both regional and national honors for "Residential Interior Under $100K" and for "Detached Outbuilding."

"Winning awards in multiple categories is difficult to do," awards director Ken Kanline said. "Not only does this speak to Platt Builders' versatility, but to their commitment to quality on every project."

Kanline added, "With these awards, Platt Builders has now won five national Chrysalis Awards in the past seven years, demonstrating their ongoing commitment to professionalism and excellence." (Earlier awards were for a kitchen, a bathroom and an addition.)

The company's latest award-winners are both local: one, a remodel of a failing carriage house, and the other, a redesigned master suite featuring a bedroom, bathroom and sitting room. Entries were judged on design, creative use of space and materials, and the degree to which the project enhanced the original structure.

The carriage house owner wanted a properly designed space to house his collection of antique Corvettes. The existing building had been damaged by rain and rot, so it was stripped to the studs, allowing for a roof extension, new insulation, siding, windows and a new concrete slab with radiant heat. The interior features hand-sanded vertical grain tongue-and-groove cedar accented with mahogany baseboards.

For the other project, the Platt team transformed a drab master suite into three bright, welcoming rooms of stylish comfort. Gone are unsightly sliders, small closets, outdated bathroom fixtures, old wooden paneling and an overpowering stone fireplace. In their place are stately new windows, a large master closet, pastel-painted walls, an elegant fireplace with a wooden mantle, custom, closed bookcases and a feeling of spaciousness created by a new vaulted ceiling in the den.

Company owner Halsey Platt says his team is thrilled by the awards.

"We take great pride in being able to deliver local service while earning national recognition," he said.