The Casa de Aguirre, like many of Old Town's original buildings, was constructed of adobe. Adobe bricks, flooring, roof tiles, and other materials were made locally by combining clay, sand, water and straw and pouring this mixture into wooden forms. Once the bricks and tiles were dry enough to hold their shape, the forms were removed and the blocks were left to cure in the sun. The bricks were ready after thirty days of drying time. The exterior walls of adobe houses were coated with plaster to protect them from damage by the wind, sun and rain. The present-day re-creation of the Casa de Aguirre used authentically made adobe bricks (exposed here) mortared onto an earthquake-proof substructure.