The Moorehead Apartments
Crystal Beach, Texas, is a gorgeous location, but there are very strict parameters for building there. Buildings are designed for extra resilience because they must withstand high coastal winds and deal with a corrosive marine environment that includes seawater floods. This means that all of the buildings in Crystal Beach must be raised at or above base flood elevations, which translates to a minimum of 17 feet above sea level.
Designers of the Moorehead Apartments, a 32-unit multifamily midrise structure, had their work cut out for them. The project engineer, Robert Dinjar and Chandra Franklin Womack, P.E. and President of Aran + Franklin, not only had to meet the stringent building code of Crystal Beach, but also plan for a few special requests from the building owner: leaving space below the building to accommodate a pool at ground level and designing an attic that can easily be converted into a third floor with leasable units at a later date. And money was an object: construction costs for the building needed to be as economical as possible.
To meet the combined goals of resiliency, durability, and cost-effectiveness for the 60- by 120-foot building, Dinjar selected wood products. The building stands on treated 12x12-inch southern pine timber pilings in combination with proprietary floor joists and preservative-treated stock glulam beams.
The first floor was raised an additional 4 feet above the required minimum elevation for two reasons: to give more headroom at the pool below and to give the owner a nice break on future flood insurance premium payments.
The entire exterior, as well as most of the interior, was sheathed with wood structural panels, creating strong, resilient diaphragm walls. To resist the corrosive nature of the marine environment, all exterior fasteners are either hot-dip galvanized or stainless steel.
One cost-saving measure Dinjar implemented was standardizing the sizing of the stock glulam beams as much as possible. Deeper 3-1/2-inch-wide treated glulam beams from APA member Anthony Forest Products made a strong yet economical substitute for shallower 5-1/4-inch-wide beams where appropriate. Easy to build with and readily available, using the deeper, more narrow glulam beams saved the owner an estimated 10 percent.
The roof design presented a challenge. Because the owner plans for future top-story expansion, the attic needed to be as open as possible, so the structure was designed with a tall gable roof—not a typical choice in a high-wind zone, but the project engineer made it work by beefing up the structure, using a double 2-x12 ridge tied with 18-gauge strapping, collar tie, and above-code rafter connections.
Creative problem-solving made it possible to achieve a clever design that met the client’s expectations while working within the constraints of strict parameters. Planning for long-term cost savings up front, such as the decision to add elevation height to mitigate insurance premiums, coupled with savvy material choices, such as the substitution of deeper glulam beams, satisfied both building code and budgetary requirements—not to mention the client.