This guide covers how each pool gets built and how long it takes. If what you actually want is help deciding between the two, read fiberglass vs gunite first, where we give you the size rule we use on site and the long term cost of resurfacing.
If you are deciding between a fiberglass and a concrete pool, the installation process is one of the biggest differences. Fiberglass pools arrive as a finished shell and drop in within days. Concrete pools are built from scratch in your yard over several weeks. Here is how each one comes together so you can pick the right fit for your backyard and your timeline.
The Core Difference
A fiberglass pool is made in a factory as one solid shell, trucked to your home, and lowered into the hole with a crane. A concrete pool is built entirely on your property, with a steel frame, sprayed or poured concrete, and a plaster or aggregate finish. That single difference drives almost everything else: how long it takes, how much it costs, and how much you can customize.
Fiberglass: Days, Not Weeks
Because the shell is already built, the whole job moves fast. You can often go from a bare yard to swimming in about 2 to 3 weeks.
- Excavation and a stable gravel base
- Crane delivery and placement of the shell, often in a few hours
- Backfilling and plumbing hookups
There is no waiting on concrete to cure, fewer contractor visits, and less chance of weather setting you back.
Concrete: A Multi-Week Custom Build
Concrete pools usually take 8 to 12 weeks. The crew excavates, ties in a steel rebar frame, then sprays gunite or shotcrete to form the shell. The concrete needs to cure, which takes time and consistent watering so it does not crack. After that comes plaster or aggregate finishing, then tile, coping, and decking. It is a longer wait, but you get a fully custom pool in any shape and depth you want.
What Is the Same for Both
The groundwork is identical no matter which pool you choose. The crew marks underground utilities, clears the area, grades a path for equipment, levels the site, and sets up drainage. Both pools need that solid foundation to hold up over the years.
Plumbing and Electrical
Fiberglass shells come with the return fittings and skimmer openings already molded in, so hooking up the pump, filter, and heater usually takes 1 to 2 days. Concrete pools need those openings drilled and sealed by hand, which adds time and cost, often 3 to 5 days.
Backfill and Decking
Fiberglass shells get backfilled carefully with gravel or sand to keep the shell stable while it fills with water. Concrete pools are usually backfilled with compacted soil since the structure is already reinforced. Both need good drainage so the ground does not settle later. Then the decking goes in, whether that is pavers, stamped concrete, or natural stone.
When Will You Be Swimming?
This is where the two really split. Fiberglass gets you in the water in about 2 to 3 weeks. Concrete takes 3 to 6 months from digging to your first swim because of all the steel, concrete, curing, and finishing steps. If speed matters, fiberglass wins. If you want a one-of-a-kind design, concrete is worth the wait.
Choosing Based on Timeline, Design, and Budget
- Need to swim soon? Fiberglass installs in weeks, concrete in months.
- Want a custom shape or depth? Concrete gives you full freedom.
- Budget: fiberglass runs about 45,000 to 85,000 dollars installed, while concrete runs about 50,000 to 100,000 dollars or more.
Either way, the build goes smoother with an experienced crew. Take a look at our inground pool design and installation services to talk through which option fits your yard.
Common Questions
Can a fiberglass pool be converted to concrete later?
No. The shell is one molded piece set into the ground. Switching would mean removing the shell and building a brand new pool, which is rarely worth the cost.
Do fiberglass pools crack in freezing climates?
It is rare when they are cared for properly. The shell flexes with ground movement better than concrete. Winterizing correctly is the key to avoiding damage.
Which has lower long-term maintenance?
Fiberglass. The smooth surface resists algae, so you use fewer chemicals and skip the resurfacing that concrete needs every 10 to 15 years.
The Bottom Line
Fiberglass gets you swimming fast with low upkeep. Concrete takes longer but lets you build exactly the pool you picture. Weigh your timeline, your design wish list, and your budget, then talk with a builder before you dig.