Briefly in the mid-1950s, Wright teamed up with Madison builder Marshall Erdman to design, build, and market prefabricated Usonian houses. The first was the Eugene Van Tamelen House (DA42) in 1956. Its plan inspired eight more Wright-Erdman house designs over the next five years, including this one. Like the others, the Iber House has a masonry core housing the family room, kitchen, and fireplace, and the other principal walls are paneled with Masonite strips, joined with battens to create strong horizontal lines. Erdman’s prefabs also used stock doors and awning windows to save money, but buyers could choose among several exterior finishes to fit their budgets and tastes. Instead of concrete block (as at the Van Tamelen House), limestone clads the core here. Random limestone slabs project to suggest a natural outcropping, although the actual effect here is less evocative than in other Wright buildings. And though most of the exterior panels and battens are painted like the Van Tamelen residence, Iber’s fascia and soffits are made of blond mahogany, resulting in a single contrasting horizontal band between the walls and the cedar shake roof.
The Iber House’s floor plan, like the exterior treatment, varied and improved upon the Van Tamelen prototype. Both structures were built in a roughly linear plan, with the family room and kitchen set off to create a slight front-facing ell. This arrangement exposed the walls on two sides of the living room, allowing more natural light to flood that space. But in the Iber House, the family room was enlarged and its windows expanded to turn the corner and provide more sunlight. The Iber plan also included a fourth bedroom, a lower terrace stretching along the rear of the bedroom wing, and an enclosed garage instead of a carport. In these ways, the building resembles the Carl Post House in Barrington Hills, Illinois, and (except for the garage) the William Cass House in Richmond, New York. In those buildings, however, brick rather than limestone clads the core.