The project added a third floor. Paul Irwin set the addition
back six feet from the original roofline so it would not
overpower the existing architecture.
The owners of this Dutch Colonial were content with their DC neighborhood and loved their big back yard. Even though they needed more space, they decided to renovate instead of moving to a larger home. It was the third time they would call on Landis Construction, the firm that had already completed two projects in their house (a master-bath addition and a basement renovation). The third project would be the most elaborate to date.
The owners were tired of their galley kitchen and wanted a larger, updated kitchen space incorporating an informal family room. They also wanted two additional bedrooms, another bathroom and a playroom for their two young children.
Designer Paul Irwin met with the owners and devised a plan. Extending a new kitchen/family room off the rear of the house made sense, but adding two new bedrooms in the back would dwarf the family’s splendid yard. “It made sense to add the bedrooms on a third floor,” Irwin says. He designed a plan that would stack a new staircase above the existing stair and create two new children’s bedrooms with a shared bath and extra storage space on a new third level. Existing attic space could be converted into a pint-sized playroom for the kids located off one of the bedrooms.
The homeowners approved the idea, and Irwin got to work finalizing the design and carefully planning the execution. He knew the plan presented a number of design and construction challenges, from creating adequate support for an entirely new level to opening up the existing roof and exposing the house to the elements during construction. “The engineering challenges posed by adding a third floor onto an existing house are not to be taken lightly,” he says. “Inherent in that, a lot of contingencies have to be planned for.”
One of Irwin’s goals was to assure that the pop-up addition would complement the home’s existing architecture and not appear out of proportion. “We did some three-dimensional studies of the house on the computer and saw the vantage points from the yard. Since it sits high on its lot, that was working in its favor,” explains Irwin. “It meant it would not appear top heavy from the street.” He set the addition back from the façade by about six feet, so that “the existing roof lines concealed it a little bit.”
On the main level, the plan converted the existing kitchen into a butler’s pantry and bumped the new kitchen/family room out the back of the home. An existing powder room would have to be moved ten feet to make way for the new kitchen. They would also install a hydronic radiant-floor system to heat the new wing.
Irwin and the owners selected a number of custom finishes in the kitchen, including black walnut countertops. “We hand-selected the
lumber from a mill in Pennsylvania,” he says. Carrera marble flanks the cooktop, while a farm sink completes the clean, simple look. A seating area faces the kitchen in the light and airy new space—a welcome change from the former galley kitchen.
The third-floor addition was far more complex. To be sure the existing foundation could support the load of an additional level, the team had to embed two 20-foot steel columns into the existing walls of the home. They also had to build a new floor system above the existing attic—a clear span with 16-inch-deep trusses from one exterior wall to the other—that would also help bear the weight of the addition without imposing additional loads on any existing interior walls.
Though Irwin prepared for the worst, the entire build-out went smoothly. His crew, directed by project manager Andrew Kerr, was able to embed the steel beams by simply making a few holes in the exterior of the house rather than demolishing finished walls. “We were able to install the columns in one continuous piece. It was a nice surprise,” he says.
Rather than building conventional framing on the third level, which would have left the house exposed for a long period of time, Irwin proposed that they frame the third level with structural insulated panels, also known as SIPs. SIPs are made from solid foam insulation sandwiched between two sheets of oriented strand board and have high insulation value. “The whole idea was to minimize site time. We were exposing the house and all of its furnishings to the weather. Speed was a big issue,” says Irwin, “so we had the SIPs pre-cut and delivered to the job site.”
Everything went as planned and even the weather cooperated. “Kerr had ripped off the roof and the whole house was vulnerable. The crew worked some long days to get the floor system and walls up so that it would stay dry,” Irwin recalls.
“We were blessed with some good weather. We had a whole-house tarp that could cover the house.The entire construction phase took about six or seven months. The wait was well worth it for the homeowners, who feel like they gained a new house in the process. The project won Landis Construction a 2005 Contractor of the Year award. But to Irwin, the best news is that most visitors can’t distinguish between the old and new parts of the house. He says, “It’s really difficult to add a third floor to a house and have it come out well. I think it’s fair to say that most people would say it belongs there.”
During construction, the last remnants of the original
roof remained as the team worked to remove it. if it
rained…we mapped out back-up plans for disasters
that fortunately never came.”
Crews hoisted and prepared to install a custom site-built
flitched beam to be connected atop the embedded steel
columns placed in the existing exterior walls.
The rear addition encompasses a new spacious kitchen with
black walnut countertops and a farm sink.
The former kitchen before the remodel.
The old kitchen was transformed into a butler’s pantry with
plenty of storage and a wet bar.
with a custom door.
A new staircase leads the family up to the third floor.
The playroom was created in the home’s existing attic space.