You can find free floating house plans online at All About Houseboats, Spira Boats, In the Boatshed and Woodworking Down Under. Companies like Berkeley Engineering, Boatdesigns.com, Marine Dynamix and Kasten Marine Design offer floating house plans for a fee. Additionally, some independent builders post their customized plans online for free.
You can also commission customized floating house designs from boat builders and marine engineering firms. Businesses like Atkin and Co., Thoroughbred Boats and Twin Anchors Manufacturing work with customers to create tailor-made plans for floating houses. Other companies such as Sumerset Houseboats offer a range of existing plans to choose from.