Case Study: Slide-By House by Estes Twombly + Titrington

Situated on the edge of Massachusetts near the border with Rhode Island, the eponymously named Westport was the westernmost port of the Massachusetts Bay Colony. It’s blessed with a rich history of agriculture and fishing, and a forked river offers miles and miles of nautical views. All these conditions still surround the Slide-By House, which Estes Twombly + Titrington Architects carefully configured in appreciation of the land’s natural splendors. 

Nevertheless, the project conjured mixed feelings for Jim Estes, FAIA. Like many conservation-minded architects, he isn’t keen on the development occurring here. “This is a rare place with farms, some of them going down to the ocean, that are being subdivided,” he says. “This lot was in the crosshairs of a field that had been there for more than 200 years, with old walls around it. I didn’t want to say no to building but tried to find a way to preserve a sense of the old fields that are still being hayed.”

Designed as a getaway for Boston empty-nesters who plan to eventually live here full time, it is the first house to be built in a field separated into four equal-sized lots measuring 1.4 acres. The design team hoped to set a precedent by placing the house on one side of the lot rather than plopping it in the middle, as is common in the surrounding subdivisions. Jim and his clients even approached the owners of the other lots to suggest the same treatment and that lawns be limited to preserve the field areas between the houses. 

The big siting consideration, of course, was the water view east to the West Fork River. Jim placed the house parallel to the street, canting it slightly toward the view and to avoid direct northern and southern exposure. The major glass areas face east, eliminating extreme solar gain in summer and heat loss in the winter.  

While the firm is known for its innovative takeoffs on local building traditions and materials, resulting in taut shingled houses that open themselves to the land, this one distills that idea further. The driveway ends at a flat-roofed carport and porch. Behind them, two 18-foot-wide rectilinear, low-pitched volumes “slide by” each other, giving the project its name. 

Identical in section, the longer volume contains the entry/mudroom; open kitchen, dining, and living space; and office. It lightly touches the parallel 3-bedroom volume at the end of a corridor, where full-height glass lets in light. “In plan, the slide-by arrangement creates the classic ‘go through the building toward the light at the end of a long passageway,’” Jim says.

The home’s low profile is a refreshing departure from surrounding new builds featuring “half in, half out” houses that sever the relationship with the land. “Because of the high water table, it’s cheaper to dig down 4 feet and have the foundation stick up 3 or 4 feet if they want a basement, and then take dirt from the hole and pile it against the foundation,” Jim explains. 

The 5V Crimp Galvalume roof is externally fastened, like the utilitarian treatment one sees on nearby barns. “We try to keep the pitch low; it’s a combination of what works visually when we’re freehanding the drawing and avoiding creating a lot of space on the interior for heat buildup,” Jim says. A more distant consideration is that the roof is “a walker,” he adds. Low-pitched roofs save money on labor because installation is easier and quicker. “You don’t have to set up scaffolding or use roof jacks; you can just walk on it.”

Strategically grouped, off-the-shelf windows also help to simplify the form, in keeping with local farm architecture. “Rather than punching out windows here and there, we tried to group them, which lets the forms read better,” Jim says. “That also makes it stronger on the interior.” The building is clad in scrappy white pine boards cut 1 inch thick by 12 inches wide. 

“We’ve been using the white pine a lot lately here in New England,” Jim says. “The trees are in their second or third growth and cut selectively. It is a native softwood tree, often very knotty. The mills we buy it from are pretty rugged outfits that use big old rotary blades. If you go less than 1 inch thick, the thickness of boards can vary by ¼ inch, which is a nice thing to take advantage of.”

The boards were air-dried on site for about eight months to increase their stability. For builder Dan Kinsella, it was a cost-efficient move that required some early planning. “We made spacers out of PVC from the lumberyard; PVC doesn’t cause moisture to be trapped between stacks,” he says. “We covered the stacks with tarps to keep them dry while allowing a lot of airflow, and then primed the boards in place on both sides with a solid-body acrylic stain.”

That unfussy sense of ease is felt inside, too. Cathedral ceilings in the main volume and bedrooms express the roof pitch and the owners’ wish for spaces that are sunlit, open, and informal. Every room is used every day except for the two smaller bedrooms, each of which has a prefabricated metal ship’s ladder to a loft, no doubt to the delight of visiting grandchildren. Outdoor terraces bracket the living and dining area—one for sitting, the other for outdoor meals. 

As well as an understated response to the setting, Slide-By House is awash in finishes that lend an airy sense of space. Flooring is constructed of 2¼-wide maple planks. The kitchen and baths are fitted with IKEA cabinets with custom fronts. In the kitchen they’re combined with open shelving, engineered stone countertops, and glass backsplash tiles. 

In the year the owners have lived there, the house has been operating at Net-Zero. Jim attributes that not just to the 37 solar roof panels but to careful, commonsense construction. “One of the satisfying things is that it achieves Net-Zero even though it isn’t super-insulated,” such as with exterior foam, Jim says. “Normally when we work to create a Net-Zero house, there’s a 20-to-30 percent premium on construction.” This was not a high-budget house, he adds, and its strong energy performance was achieved by following industry best practices such as meticulous framing, sheathing, and taping, and filling the stud bays with foam. 

Few embellishments were needed, or indeed desired, outside the house either. The immediate landscape was intentionally kept spare as befits the pastoral setting. Only a board-formed concrete site wall defines the small, freeform lawn that pushes up against the terrace, with the meadow grass as a billowy backdrop. 

Slide-By House

Westport, Massachusetts

Architect: Jim Estes, FAIA, Estes Twombly + Titrington Architects, Newport, Rhode Island

Builder: Dan Kinsella, Kinsella Building Company, Portsmouth, Rhode Island

Project size: 2,150 square feet

Site size: 1.4 acres

Construction cost: Withheld

Photography: Warren Jagger Photography

Cabinetry: IKEA with Kokeena fronts

Cladding: Locally cut white pine

Countertops: Caesarstone

Decking: Accoya

Entry doors: Weather Shield

Faucets: Blanco, Kohler, Grohe

Finish materials: Radiata pine trim

Flooring: Maple

HVAC: Fujitsu, Lifebreath HRV system

Insulation: Icynene closed and open cell foam

Landscape pavers: Cast concrete

Lighting: Dals, Poulsen

Lighting control systems: Lutron

Outdoor shower: Central Brass

Paints/stains: Benjamin Moore

Passage doors/hardware: Flush maple S.C. doors, Kwikset levers

Millwork, molding, trim: Locally cut white pine

Refrigerator: Sub-Zero

Roofing: 5V Crimp Galvalume

Sauna: Finlandia

Sinks: Create Good Sinks, Grohe, IKEA

Skylights: VELUX

Surfacing (other than counters): Laminate

Toilets: TOTO

Tub: Americh

Weatherization/Underlayment: ZIP System, ¾-inch AdvanTech subfloor

Windows/Window Wall Systems: Weather Shield