There’s no doubt that fiberglass pools have a stronger presence than just a decade ago.
For example, one PSN Top 50 Builder, Pools of Fun, has been installing fiberglass pools for 17 years, adding it to their vinyl-liner offerings well before it became the hot item it is today. In that time, they’ve seen fiberglass gradually increase to about 50% of the pools it builds annually, says Tyler Hermon, vice president of sales and marketing for the Plainfield, Ind.-based builder.
Already increasing in market share, fiberglass pools became even more popular during the pandemic, as families looked for alternatives that would allow them to swim with a minimal wait.
But, while this product may go in the ground more quickly than other pool types, that doesn’t mean they don’t require attention and expertise.
This may be lost on some, especially those without a history of building pools. “We get this a lot from customers: ‘Well, you just dig a hole and you put a pool in there,’” says Phil Copher, owner of Epic Escapes, in St. Charles, Ill. “Yeah, it is, but there’s a lot more to it. A heart transplant may be just cutting out the old one and putting in a new one, but there’s a lot more going on.”
Here, Copher and other installers share advice for ensuring a solid fiberglass-pool installation.
Invest extra time in your vendor relationship.
So much of a project’s success rides on the shell. For this reason, Michael Durand recommends starting with a solid working relationship with your fiberglass pool vendors.
“It’s not a piece of the pool — it is the pool,” says the co-owner of J&M Pool Company in Senoia, Ga. “It’s not only a product, but it’s a very expensive product.”
Establish a good relationship so that you’re on the same page when questions, challenges or warranty issues spring up, he recommends. It’ll make these issues smooth out more quickly.
Don’t oversell installation speed.
While the shell can be set in a day or two, that doesn’t mean it’ll be ready for swimming. Decking and other more complicated features will add at least a few days.
But customers often believe they can swim in a day or two.
Provide realistic time lines, and explain all that’s involved in the pool and accompanying amenities.
Use in-house crews.
If these builders install enough fiberglass pools to keep a crew busy full-time, they will train a dedicated group. Until they reach that volume, they’ll cross-train crews to work in multiple formats. Some will cross train all crews just in case, but mostly dedicate each to one specialty.
Whatever approach works best for your company and available staff, Durand highly recommends sticking with in-house workers. Fiberglass pools have their own rhythm — certain steps must move fast, or in quick succession one after the other; others require more time, patience and precision. It’s hard to control those things with subcontractors.
Prevent voids in the base.
Remember that a one-piece fiberglass pool is just that — a complete vessel that comes in one piece. And you will have to set that whole pool on top of a base that is made for it. It’s not like concrete, which you will shoot or pour in place. Crews need to prepare the base so it meets right up to the pool shell, with no gaps.
It starts at excavation. Pools of Fun uses a laser transit to make sure the elevation and slopes are just so.
This requires close communication. “The guy in the excavator and the guy with the grade stick kind of work as a band,” Hermon says. “He’s telling the excavator whether we’ve reached the depth or whether we need another 1 or 2 inches down.”
Even more precision is needed when setting down the gravel base.
If the base isn’t done correctly, there will be gaps, leaving hollow pockets underneath the pool floor. “So when you walk on the floor of that pool, it will actually flex underneath your feet,” Hermon says. “The homeowner will feel that — the floor will feel like a hollow void underneath.”
Of course, working with a solid base material is crucial. Builders used sand at one time, but they’ve moved away from it and now largely use gravel. “Sand can move around underneath and on the side of the pool,” Hermon.
Many use pea gravel, known for its self-compacting characteristics. Others prefer a chip stone, which is known for interlocking and staying in place.
“Once it’s all locked into place and compressed, the walls technically can relax, and it could almost stay in its exact same spot,” Copher says.
After the pool’s been set in place and is believed to be level, Hermon’s team will walk around the pool and bounce, searching for any hollow areas that indicate a gap in the sub-base.
“If there is [a gap], that’s when we would flip the pool back up and add gravel to those specific spots,” he says. “And that’s a dance that we do until we’ve really made sure that there are no voids underneath the pool. ”
Keep it on the level.
Leveling the pool is arguably the most important step in the process. Poor execution of this step affects more than the pool’s appearance.
“That, over time, can form cracks and deform the pool and be a larger issue down the road,” says Rob Goodall, vice president of Goodall Pools in Camp Hill, Pa.
His team shoots the top of the pool with a laser and strives to keep the pools within ¼-inch of level.
“If it is more than that, we’ll usually pull the pool back out and spend the extra hour or so to try and make the base of the hole that we’ve dug work with the bottom of the pool, so that everything sits much more level,” he adds.
Builders must backfill the pool at the same time as they fill with water. To equalize the pressure on both sides of the shell, they should be done at the same rate. Many recommend that the levels of the backfill material and the water remain within 12 inches of each other throughout the process.
This is especially important for straight-walled pools. “When the wall’s long and has nothing connected to it, you can literally use your hand and move it a foot in either direction ,” Copher says. “If it’s got a long, straight wall and it’s 40 feet, you really have to almost balance it identically. If not, you’re going to run into issues with it bowing one way or another. ”
This doesn’t mean you have to fill and backfill in one day. You can start by filling with enough water and gravel to secure the pool in place overnight, then finish it the next day.
When performing this step, monitor the water and backfill levels closely. When he worked on the crews, Copher would drive the skid steer that brought and dropped the gravel into place. Before he left for another load, he’d quickly eyeball the levels, then check again when he came back to the pool with the gravel. That would tell him where to drop the gravel next, and help him ensure the levels fell within 12 inches of each other. Other times, his crews assign one person to watch and direct traffic.
“They’re standing on the back and looking at what’s in or out more than the other, and they’ll point and say, ‘Okay, let’s work on the left side.’ Then the next bucket is on the right side,” he says.
When you see the walls bowing about 1 inch from level, it’s time to make adjustments. If it falls 2 inches from level, the crews should stop the process, assess and correct.
“I always tell my guys, ‘You’re going to work so much harder if you rush that process,’” Copher says.
This is especially important if you’re using a water truck, which fills the pool much faster than a hose. With the water coming into the pool so quickly, things can go uneven in a flash.
Correction isn’t easy or quick. “That can involve setting the pool and lifting it back up, and setting it back down and lifting it back up,” Hermon says.
So whether you use a crane or an excavator, plan to have the equipment on hand until you’re certain the pool is level.
Don’t rush the plumbing.
Once a cut is made in the fiberglass shell, there’s no going back. So plan the cuts carefully and do them precisely. A misplaced hole can’t be covered with vinyl.
“All your cuts must be extremely intentional, or you can cost yourself a lot of money or ruin a pool shell; if you make the wrong size or put it in the wrong place, there’s really no reversing that,” Hermon says.
His team indicates the placement and measurements of the fittings on the project’s Autocad drawings for reference. These show all fittings, skimmers and lights that go in the pools.
And an extra bead of silicone around the fitting is always a wise move, he adds.
Flex pipe should not be used on swimming pools in general, and fiberglass is no exception. While some builders may be drawn to its ability to move where you like easily, it won’t hold up as well as rigid plumbing.
“I think a lot of the failures in the fiberglass world come from using flex pipe, in trying to do one-day installations,” Copher says.
The plumbing should sit near the top of the bond beam and be supported by straps.
“So we’re giving our plumbing penetrations that go through the pool its best shot that it won’t settle and crack,” Copher says. “Because if there’s no support on the plumbing itself and you’re relying on just the fitting, then you’re going to run into issues.”
