Yes, you can build a stand-alone custom spa without a pool. A gunite spa can boast some of the same decorative features as a gunite pool.
Building a free-standing spa can cost almost as much as a small gunite pool. That’s because each specialty crew must come to the job site to complete each of the various construction phases—just as they would for an entire pool.
Despite the investment, some homeowners still choose to build a stand-alone gunite spa. They won’t settle for a portable hot tub because they want an attractive, permanent custom backyard amenity—versus a prefabricated vessel sitting on the ground.