Few home design elements provide the instant wow factor of freestanding tubs. Freestanding tubs have an air of luxury that can help current homeowners relax, and impress buyers when homes go on the market.

Freestanding tubs are typically made of cast iron or porcelain. The home improvement website HomeAdvisor notes that cast iron is durable and solid and retains heat well, which is great for those who want to spend more than a little time relaxing in a freestanding tub.

However, because cast iron is so heavy, installing a cast iron tub may require structural reinforcement of the flooring,...