One of the hallmarks of a skilled architect is to keep a project on budget. But what if the commission is on a secluded coastal island, and the owners want a 1,600-square-feet home on a budget of just $150,000?

“My initial response was ‘No way!’” says leading Raleigh-based architect Frank Harmon when he first met Boston couple Sabrina Terry and Jon Lampe at their 16.5-acre property on South Carolina’s St. Helena Island.

“They’d been camping out there in the summer,” says Harmon. “There was a bathroom structure and a tent with mosquito netting.”

Harmon was taken with their south-facing landscape on the Harbor River, where cool breezes slipped across the water and the southern exposure delivered warmth in winter. But still, there were the limited finances.

The architect persevered, exploring options like homes on wheels to sidestep flood plain zoning issues, even a trendy “tiny” home. Then he hit upon an idea, and it stuck.

The result is an eye-catching home, 50 percent of which is composed entirely of screened porches.

“Screened porches can be built for a fraction of the cost of heated space,” says Harmon, “and since the climate in Beaufort County rarely freezes, the owners can live outdoors for nine months of each year.”

To comply with flood plain regulations, the house sits on 14-foot pilings and is sited to maximize solar orientation, capture prevailing breezes for natural ventilation, and enjoy the idyllic river and island views.

A siding glass door protects most of the screened-in living area from cold north winds. The cypress framing and rain-screen exterior, as well as the heart pine floors, were felled and milled within 50 miles of the property.

The sloped aluminum roof reflects heat in summer and provides a corrosion-resistant, energy-efficient roofing system ideal for this coastal climate. A deep overhang shields the interior from the high summer sun, but allows the lower winter sun to enter the space.

A mini split-HVAC system heats and cools the interior when needed. The house operates on a tankless water heater, and the couple benefit from $100-per-month electricity bills – a big result on a small budget.

For more information, visit frankharmon.com.

Image Credits: Photos by Richard Leo Johnson.