Deck builders report strong demand for health and wellness features like saunas and hot tubs as more homeowners seek to create an outdoor spa experience. Hot tubs are especially popular. “We install a lot of them,” says Jonathan Moeller of Colorado Custom Covers & Decks. “We've had periods when just about every customer wanted one.”
Of course, a deck with a hot tub requires careful planning—from placement to structural support—to ensure a safe and enjoyable experience.
Start with smart placement
The first step is to work with the homeowners on where to put the tub. “Do they prefer to be under a roof cover or under the night sky where they can look up at the stars and get snowed on?” asks Moeller. “A lot of people go back and forth on this before making a decision.”
Where a tub can be located depends in part on what will be nearby. “It has to be at least three feet away from windows,” cautions Moeller. “You don't want someone falling off the edge of the tub into a pane of glass.” Windows closer than 3 feet away need to be made of tempered glass.
Moeller works in Colorado’s Front Range on the western edge of Denver, where homeowners use their tubs year-round, so he also has to plan for ice and snow. “We keep tubs at least two feet away from deck railings,” he says. “That's enough room to shovel snow around the tub to prevent it from melting and then re-freezing into an ice dam.”
Choose the right surface
When it comes to the decking, the amount of water that will get splashed onto it from the tub makes slip resistance non-negotiable.
Moeller uses decking made with Surestone technology from Deckorators. “It’s a mineral-based composite with an anti-slip texture, which is the main reason I switched to it,” he says. “Other companies’ decking can get real slick when wet, but the Deckorators product actually gets more sticky.”
Engineer the deck to bear the load
The most obvious design issue when building a deck with a hot tub is the tub’s sheer weight. The International Residential Code requires that a typical deck be capable of supporting a live load of 40 pounds per square foot, but an 8- x 7-foot tub with 3 feet of water can more than triple that, ranging up to 8,000 pounds. (That's heavier than a Ford F-150, which weighs in at around 5,000 pounds.)
The framing around the tub has to be strengthened, which may mean including a thicker girder and/or more joists. “In some instances we’ve had to tighten joist spacing from 12 inches o.c. to 9,” says Moeller. “A lot of times we’re doubling joists as well.”
The extra weight will also require a more secure connection between the deck and the house, which will mean additional bolts as well as other considerations, according to Chris DeBlois, P.E., of CDF Structural Engineering in Roswell, Georgia. “For instance, if there’s a window or door below the band where the deck connects to the house, the header probably wasn’t designed for the extra load imposed by the tub. We may have to upgrade a header, add jacks, or reinforce the framing,” says DeBlois.
This raises the question of whether the plans will need an engineer’s stamp. In the jurisdictions where Moeller and DeBlois build, as in many others, it’s a requirement. Even if your local code does not mandate it, however, involving an engineer is still a smart move.
“For the typical deck with a hot tub, I’m charging only an hour or two of my time to review the plans,” says DeBlois. “That’s cheap insurance that can save the contractor a lot of trouble.” He adds that an engineer’s stamp will also allay homeowner concerns and enhance your reputation. “It shows that you’re serious about quality and safety.”
Building a deck with a hot tub isn’t difficult—but it’s also not business as usual. It takes smart materials choices and thoughtful planning. Done right, it creates an outdoor sanctuary that is safe, durable, and deeply satisfying. Your ability to provide those results is why your customers come to you.
To see what else is trending, download the Deckorators Outdoor Living Report.
