
FRANK LLOYD WRIGHT’S “WINSPREAD”
Wingspread was designed by Frank Lloyd Wright and built in 1938-39 as the residence of Herbert F. Johnson Jr. The house is now used as a conference facility by The Johnson Foundation. The home is centered around a large domed living room. However, like many of Wright’s designs, it pushed the limits of the structural systems that were available at the time of construction. Due to excessive snow loading and remodels which removed shear walls, the exterior bearing walls had pushed outward and the roof of this dome had begun cracking. In partnership with Robert Silman Associates, WRD engineers developed a replacement rafter system that would maintain the aesthetic appearance from both inside and outside while greatly increasing the strength. The system that was developed consisted of several layers of epoxy-coated carbon-fiber-reinforced plastic (CRP) face-bonded to laminated veneer lumber (LVL).