Following a scary incident in which one of her young children nearly drowned, our client—a single mom—decided to "retire" the pool of her recently-purchased home. Simply burying or removing the pool wasn’t an option, however, as she wanted to retain its value for possible restoration by a future owner. That’s where my company—Deckover—came into the picture. For the past 13 years, our Phoenix-based deck building company has specialized in decommissioning pools and adapting them to other uses.
In this case, our client chose to build a rectangular step-up deck set completely over the free-form pool because she wanted no visible reminder of the traumatic event that precipitated the deck construction. We framed the deck conventionally with galvanized steel joists that rest on the pool edges and span its 16-foot width, and we finished it with ChoiceDek composite decking and a matching composite skirt around the perimeter. To provide access below the deck, we added a hatch.
Since rainwater accumulates in the pool beneath the deck, we always include a sump pump placed over the pool drain. The pump is powered by an electrical circuit that once powered the pool lighting and is activated by an automatic pump controller of our design. The controller turns the pump on when water rises in the bottom of the pool, expelling it through the pool’s skimmer return line.
We added a powder-coated aluminum Alumawood pergola for shade at one end of the expansive deck, using the deck structure for support.
Of course, there are other factors compelling homeowners to retire their pools. On another project, for example, our clients simply grew tired of the annual maintenance and wanted to use the space to create a kid-safe and adult-friendly backyard living area. Our approach in this case—to orient the pool cover so that it would be flush with the top edge of the coping around the pool—was more typical of the majority of our projects and meant that the deck framing had to be inset.
A deck that rests inside rather than on top of a swimming pool has several inherent difficulties, of course. The most obvious is that, when it comes to pools, there is no such thing as a straight edge. Even a rectangle is not really a rectangle when poured using concrete forms, and many pools have nothing that is even close to a straight edge. The worst are those with "Drooping Snowman" or "Mickey Mouse" shapes, where the designer takes three circles and smooshes them together in a dogleg orientation.
Instead of hanging the deck framing from the sides of the pool (which presents several problems), we’ve developed a process that allows us to prefabricate the frame in sections. First, we use an RC drone to take overhead photos of the pool, which we drop into CAD to create accurately dimensioned drawings. We have our shop set up with a ceiling-mounted projector that allows us to reproduce a full-scale drawing on the floor, which we use to lay out and assemble the framing using standard galvanized light-gauge-steel track and joist components.
These prefabricated sections are light enough to be loaded by hand onto our work trailer and hauled to a jobsite. There, we reassemble the sections, supporting them with a series of cross beams set at the proper elevation to ensure that the top of the composite decking is flush with the top of the pool.
It’s a tricky process, though. For one thing, it’s hard to accurately map the shape of some pools, and concrete walls don’t move when one of our dimensions is off. Meanwhile, composite decking has very little overhang allowance, so the framing has to be close—within a few inches—to all sides of the pool. And this project had an added challenge: a step-down fire pit, which is located in the deep end of the pool. To create it, we fabricated a round frame, rolling the steel track on a special machine to give it its shape. But the effort was worth it, as the propane-powered fire pit has become s’mores-central on weekends. After the little ones are tucked into bed, adult members of the family gather around for long conversations under the stars.
The composite decking around the fire pit and at the larger end of the pool is AERT’s MoistureShield, while the center section of the deck has a plywood cover with a special acrylic coating for weatherproofing. Again, we built a hatch into the structure to provide access below deck for extra storage and to maintain the sump pump at the bottom of the pool. LED rope lighting around the edge of the deck inserted in the space created between the new deck and the old bull-nosed pool coping further enhances the ambiance of the space. The owners tell us that they now use their backyard far more than they ever did when they had their pool.
