Sometimes you can add on without paying an energy penalty.

The owners of this 1960s ranch house loved their house but it wasn't configured to meet their needs. Despite its generous square footage, the house had only two small bedrooms for the family of four, and there was no casual living space for parents and kids to hang out separately.

As remodelers we encounter this all the time: people live in homes whose space plan is out of sync with their functional requirements. In most cases we strive— and indeed are able—to resolve this problem by redesigning existing spaces. But in this case we couldn't.

The house featured a large, open living room with a central chimney. Access to two small bedrooms was off one side of the living room, while a kitchen, den and porch were off the back. Chopping up the living room wasn't an option—both for structural reasons and because the owners wished to preserve the openness of their home. We saw no alternative but to add on.

At the same time neither we nor the clients wanted to increase the home's energy usage. In fact we were hoping that when all was said and done, the house would use less energy than before, despite the fact that there would be more space to heat and cool as well as additional electrical loads. 

It was a tall order: could we increase the home's size without increasing its energy footprint?

Gaining Living Space While Saving Energy

  • Gaining space exterior 2, after
  • Gaining living space exterior, before
  • Gaining living space exterior, after
  • Gaining living space basement, before
  • Gaining living space basement family room, after
  • Gaining Living space, new basement bedroom
  • Gaining living space, new basement stair
  • Gaining living space, new bathroom

Byggmeister's Solution

The key to meeting this challenge was a rigorous and integrated planning process with early-stage energy modeling accompanying design. As the architect (Anita Rogers) worked out the space plan, the energy consultant (Mike Duclos) analyzed how various scenarios could be combined with envelope and mechanical packages to not only hold the line on energy use but improve performance. We anticipate the plan we settled on will save 25% annually over pre-project energy use.

Functional requirements were met with two small additions, one at the front of the home and one off the side adjacent to the two existing bedrooms. These new spaces provided an additional bedroom on the main level as well as a new stair down to the basement. At basement level, the additions yielded a guest room,  a full bathroom and a laundry area. The existing basement, which is now easily accessible from the main floor, was refinished as a casual family room.

Anita designed the new spaces to be spare and bright, replicating the mid-century aesthetic. Every detail—from the open stair, to the light maple floors, to the detailing of the bathroom vanity—echoes the vintage and character of the original home.

We specified extremely high levels of insulation in the additions and took advantage of every opportunity to improve the efficiency of the existing house. We insulated the entire basement to the same levels as the additions; added 2" of exterior insulation to most of the existing above ground walls; filled the existing attic space with dense packed cellulose; and installed triple-glazed, high performance windows throughout.

We replaced the old gas furnace with a new high-efficiency furnace to heat the existing home. In the new spaces, we met cooling and heating needs with ductless minisplit heat pumps. A steady supply of fresh air is supplied by a whole-house heat recovery ventilation system.

As we do with all projects, we're tracking energy use to quantify the impact of our work. Not enough time has passed yet for us to know whether we achieved the projected energy savings, but we're optimistic. In the meantime, the clients are thoroughly enjoying the new functionality of their renovated home.

Project Location

Belmont, MA