The builder of the Oldest House was Richard Cussans, who immigrated to the Island of Key West in about 1826 from the Bahamas. He was in his mid-twenties when he built the house. He may have trained and apprenticed as a ship’s carpenter but he would not have been a shipwright at that young age. That level of craft was not easily achieved. He owned slaves, and likely used their labors in the construction of the Oldest House in 1829. He was an enterprising and talented young man who built several of the original buildings on the island which he either sold or rented out. Several other structures he built have not survived. It is believed he left Key West in the late 1830s and sailed west to the new Republic of Texas.

The house was built from lumber sourced in South Florida. That may have included cypress, cedar, and most certainly Dade County Pine (Pinus elliotti var. densa). These wood materials are renowned for their durability in Florida’s harsh environment. A frame was built of large timbers, without the use of nails, which stress the wood and can cause cracks and splits. Joinery, mortise and tenon, posts and beams were fitted together mechanically and secured with holes bored and pegged. A method used in wooden ship building, this creates and tight and rigid structure that is unlikely to fail from cracks and breakage due to stresses. Additionally, the framing was sheathed on both exterior and interior supporting walls with one inch thick pine boards using cut nails. This box-in-a-box construction made the building even more rigid and tough.