Hawthorn Builders specializes in luxury custom homes built with the highest attention to detail and quality — and their recent project in Marshfield, Massachusetts, is the latest proof. The stunning 8,600-square-foot beachfront property isn’t just aesthetically pleasing, it’s designed from the inside out for the utmost in energy efficiency and weather resistance.
Building Envelope Designed to the Detail
Situated on Massachusetts’ South Shore facing the Gulf of Maine and the North Atlantic, the Marshfield home is subject to ocean currents and strong winds. From the get-go, Hawthorn Builders knew they wanted to design a robust building envelope to maximize efficiency and comfort for the climate conditions as well as meet Massachusetts’ stringent energy codes.
They framed the house with a combination of dimension lumber and engineered wood, along with steel for the moment frame on the ocean-facing side. The sheathed assembly features insulation board sandwiched between two layers of ½” plywood. This combines with closed-cell cavity insulation and an additional layer of exterior insulation board for a whole-wall R-value of 30.
For the envelope, preventing air and moisture infiltration while allowing the cavities to dry out was critical. The team opted for a Benjamin Obdyke system combining VaporDry SA underlayment and AeroNet wall and roof ventilation mat. Self-adhered and vapor-permeable, VaporDry SA ensures breathability, allowing trapped moisture from the conditioned attic or home interior to escape. VaporDry SA also self-seals around fasteners, so it can act as an air-control layer as well as a moisture-control layer.
Meanwhile, AeroNet wall and roof ventilation mat provides the convenience, light weight, and flexibility of a rolled rainscreen with superior compression resistance. This creates space behind the finish material to allow for air flow and drying, particularly critical for the walls, which were clad in cedar shingles.
While VaporDry SA typically is used just for the roof, the Hawthorn team felt its robust protection in combination with AeroNet was in keeping with the company’s mission to deliver ultimate performance no matter the local conditions.
“After speaking to a Benjamin Obdyke rep, we made the switch to VaporDry SA because of its breathability — we liked solving a problem before it happens,” says Maarten Bray, Senior Project Manager for Hawthorn Builders. “We were pleased with how it turned out. It looked clean and went on well — even the wind wasn’t a factor.”
To further fortify the high-performance envelope, the team used Benjamin Obdyke HydroFlash LA liquid-applied flashing around window flanges and pans, as well as HydroFlash UV+, a high-performance, UV-stable flashing tape, in all other areas.
Knowing the success of the building envelope relied on proper detailing, Bray installed several sections himself to establish baseline standards for the crew, installed the largest window units alongside them, and then provided close oversight after that. After the envelope was dried in, the jobsite experienced a lot of driving rain, but the team saw no failures in the system.
Along with ensuring proper performance, Hawthorn wanted to maintain visual appeal throughout the build because the jobsite was in a high-traffic area and several of the products were new. “A good-looking product sells itself,” Bray says, noting that crews also taped off the liquid-applied flashing so everything was square. “We wanted it to look nice and clean.”
Beauty by the Beach
The high-performance roof and wall envelope provides a foundation for a range of other energy-saving features throughout the home, including a solar array with backup generator, all-electric HVAC, and LED lighting. Currently, the builder is designing to or beyond standards established in the Massachusetts Stretch Energy Codes, even though those codes have since been pulled back, and they have built several projects to net-zero. It’s all part of a conscious effort to deliver efficiency beyond what others in the area are providing.
With energy efficiency and quality construction largely hidden behind the walls, homeowners and guests in Marshfield may be taken in most by the sweeping gulf views and high-end interior finishes. But they’ll do so with confidence and peace of mind knowing the home is protected by a robust, well-planned, and expertly executed high-performance envelope.
