Efficient home design and lessons from the Foursquare Farmhouse

by Aaron Hoffmans, AIA

Three years after the 2008 housing crash, builders started building homes again—but with fewer workers. Ten years later, the residential building industry still hadn’t fully regained its pre-2008 labor force. During this period, material costs slowly increased—and then dramatically climbed during the pandemic. The decreased labor force combined with increased material costs have dramatically increased overall new home construction costs—a reality which has fostered a renewed interest in finding ways to reduce them.

The custom home-building process is focused on first meeting a homeowner’s goals and constraints, before seeking design efficiency—leading homeowners to manage their budgets based on the home’s overall size and perceived per-square foot costs. This is a fine place to start, but the best way to reduce cost—whether constructing a house or manufacturing a car—is finding efficiency in both design and construction.

Sears & Roebuck understood this back in 1908 when it started offering mail-ordered homes. After a few years selling homes, Sears realized it needed to get more efficient at constructing and shipping homes in order to increase sales. This led Sears’ team to develop pre-cut lumber (now studs), plasterboard (now drywall), and asphalt shingles, to name a few—all products still used today, some 100 years later.

Further, over the last century, the construction industry has continuously created efficiencies in manufactured products. So before designing an efficient home, start by utilizing efficiencies already used in the building industry. Plywood, or oriented strand board (OSB) sheets, and drywall board come in 4-foot widths. And building codes require wall framing wood studs spaced either every 16 or 24 inches apart. Therefore, it makes sense to utilize the 4-foot module when laying out the home’s footprint and individual room sizes. (More on this later.)

Design efficiency also begins at the macro level with the home’s shape. This was understood in the late 1900s with the emergence of the American Foursquare Farmhouse design (see Exhibit 1)—a square-shaped home that simplified construction through efficient design.

 Exhibit 1: Foursquare Farmhouse Design

The square in Foursquare says it all: We’ve known since the Greeks that a square is more efficient than a rectangle. A great example is Euclid’s proof of Pythagoras’ Theorem (see Exhibit 2). A 20’x20’ shape has the same square footage as a 10’x40’ shape, but the 10’x40’ shape has 25% more linear wall space (100’ vs 80’). The closer the overall home’s shape is to a square, the more efficient it will be with material usage. As discussed, the 4-foot module width maximizes product usage while reducing waste. Therefore, use this module to lay out interior room sizes, exterior window locations and overall perimeter distance to efficiently maximize material usage.

Exhibit 2: Euclid’s Proof of Pythagoras’ Theorem

In addition to the home’s shape and the 4-foot module, circulation is another contributor to design efficiency. Office high-rise towers are designed with a core, which contains the vertical circulation system and the primary structural and mechanical systems. This central location provides maximum floor-plate efficiency (leasable space), which historically has been around 75%-80%, or 20%-25% for the core and exterior building envelope (wall).

While this metric doesn’t translate directly to residential homes, the concept of centralized circulation does. Homes, like office towers, are most efficient when circulation is centralized to maximize useable space. When designing an efficient home, centrally locate a u-shaped stair on the longitudinal axis. The u-shape allows the stair’s landings to be located internally, away from the exterior wall at the interior hallway or horizontal circulation. This reduces a hallway’s distance to a few feet on each floor from the stairs and increases floor-plate efficiency. An achievable floor plate for a residential home is around 80%, or 20% for stairs, hallway and exterior walls.

A centralized circulation scheme is enhanced by a multi-story home. A two-story home with a basement (location dependent) is best, but an attic level can easily be accomplished with an appropriate roof design.

Good design doesn’t require complicated solutions, just solutions that utilize efficiencies and guidelines already used in the construction industry. To illustrate these guidelines, I’ve created a simple house design based on a 4-foot grid that is slightly rectangular with centralized circulation. The layout utilizes common room types and sizes used by Hoffmans Architecture when designing custom homes. The design example and additional information on an efficient home design can be found in our Home Building Resource page.