Fiberglass Pools vs Vinyl Liner and Gunite: Everything You Need to Know
When it comes time to add the single best possible outdoor living feature, you won’t get a much better answer than an inground pool. The sheer prospect of spending just a few hours of time chilling or playing in a pool makes it hard to wait for summer. A public pool, even if it’s in the most exclusive country club, still doesn’t have the same appeal as a private backyard pool. And now’s the right time to get started. You can’t make summer come any faster, but you can be ready with the perfect pool as soon as the weather says, “Anybody wanna go for a swim?”
The biggest decision is choosing the pool material. Swimming pools are either gunite (concrete), vinyl, or fiberglass, and in some cases special glass (perfect for hillside infinity pools). In this article, we’ll cover why fiberglass pools are the best choice over gunite pools/concrete pools and vinyl liner pools for most people. Of course those who want a guitar-shaped pool will go with gunite or vinyl but in most cases, a fiberglass option is an all-around better choice. Here’s why.
What are Swimming Pools Made Of?
When you think about the concept of a pool, it seems pretty simple right? Pools seem to be just holes in the ground that are filled with water, but the materials they’re made of can make a big impact on their appearance and customizability, the way they fit into the landscape, practical functionality such as routine maintenance, and their longevity.
What are Fiberglass Pools?
A fiberglass pool is made entirely of a reinforced fiberglass shell. Fiberglass, much like the insulation in the walls of your home is a composite of plastic fibers and glass fibers. As insulation, fiberglass comes as a soft and cotton candy-like format designed to trap air and regulate temperature.
As a pool material, fiberglass is compressed to the point that the plastic and glass components melt together into a hard, thick, incredibly strong, light, and watertight shell.
To increase the tensile strength throughout the pool’s structure so it can withstand the dual pressures of water and soil, fiberglass pool manufacturers will often reinforce the fiberglass with additional metal wiring. While fiberglass is greatly resistant to stains, it will still be coated with a light layer of hard gel. This will not only add extra protection to both sides of the fiberglass shell, but it will also make the texture a little smoother to the touch.
Fiberglass pools can truly be molded to any practical shape in a pool design. The typical fiberglass shell pool structure is entirely factory-built offsite and assembled as a single unit in your backyard, though a larger fiberglass pool can be assembled on site from many smaller pieces.
What are Vinyl Lined Pools?
A vinyl lined pool is made up of two central components: a reinforced steel structure encased in a sealed vinyl liner. Though they can be built to an existing design, vinyl lined pools can be completely customized according to the needs of the homeowner and the demands of the landscape.
Vinyl is particularly resistant to mold growth and can withstand UV radiation damage from prolonged exposure to sunlight. Perhaps most interestingly, vinyl liners for pools can be changed after the initial construction to replace any damage or refresh the look of the pool.
Unlike fiberglass pools, vinyl lined pools are constructed on site, necessitating a longer construction period. If you’re going for a custom look, this wait is worth it; but if a fiberglass pool has the look and features you want, you could be swimming in weeks rather than months.
What are Gunite Pools?
A gunite pool, also known as a concrete pool, uses the oldest construction techniques still used in modern swimming pools. The construction of a gunite pool begins with the application of a steel reinforcement structure. Gunite is a type of concrete that is mixed into a fine slurry and blasted through spray tubes, or “guns.” As it is applied at a high velocity, gunite quickly forms the structure of a pool and is one of the fastest concrete applications used in construction. Gunite is also used to stabilize roadside cliffs that are prone to erosion and dangerous rockfalls.
Gunite pools, like vinyl lined pools, are entirely constructed on site, which enables full customization. However, gunite pools require a considerable amount of time for construction as the stone material sets and cures over the course of a few weeks. During this time, the poolside landscaping will be taking shape so once the pool is ready to be filled with water, your backyard paradise will be complete. Like with vinyl pools, the wait is worthwhile if you want a custom pool with a specific look.
Are Gunite Pools and Concrete Pools the Same?
Frankly speaking, gunite is a type of concrete. However, this does not mean that they are exactly the same. Most forms of concrete include large pieces of rock aggregate. Gunite, by contrast, is entirely built of fine stone particles and water to create a thin slurry that can move through the tubing and tip of a concrete gun. Though there is a difference between the two terms, you can expect that any pool referred to as a “concrete pool” is one and the same with a gunite pool.
Why are Fiberglass Pools Better Than Vinyl or Gunite?
The current trend in pools has been toward the convenience and great features and benefits of fiberglass pools. This is certainly in response to the improving technology of fiberglass pool construction, brought about by cheaper materials, innovative designs, and the sheer speed of installation. In fact, the speed of fiberglass pool installation is what sets fiberglass pools apart from both vinyl lined pools and gunite pools.
Let’s say that starting from day 1, it’s entirely possible to start swimming within 3 weeks whereas the other pool types will take several months from start to finish.
What are the Benefits of a Fiberglass Pool?
By this point, you already know how we feel about fiberglass pools and why they’re a better choice for most homeowners. Now, let’s take a deep dive into each of the 10 fantastic benefits that fiberglass pools have over their gunite and vinyl lined counterparts:
Huge Selection of Styles
You may feel like you’re ordering a custom pool when you browse through dozens and dozens of models, each of which may come in various sizes and color options. And yet, you’re getting a prefabricated pool including specialty pools like a pool that fits into the “plunge pool” category, also known as a cocktail pool or dipping pool. Just barely bigger than a large hot tub, these pools are basically meant for cooling off on a hot day, and for the visual aesthetics they bring to a backyard. They are ideal for small or awkwardly shaped backyards and you don’t even have to go custom to get the perfect style.
Better Insulation and Lower Heating Costs
Fiberglass pools are made of the same materials that keep your home warm in the winter and cool in the summer. In pools, this fiberglass compound is compressed into a hard shell that creates a watertight and incredibly durable pool structure. Inground pools tend to warm up with the temperature of the soil rather than the air, which can make them uncomfortably cold in the spring and early summer. In order to get the most out of your pool, you’ll look towards adding heating elements. Fiberglass pools are great at retaining this heat which lowers the costs of heating your pool in the shoulder seasons.
Compatibility with Saltwater Systems
Fiberglass pools are the only major pool material that is compatible with saltwater systems. Many homeowners have been choosing saltwater in lieu of using chlorine and other harsh chemicals. Though it’s not as effective as chemicals in cleaning a pool, saltwater eliminates the majority of bacteria and inhibits the growth of algae. If you’re looking to install a saltwater pool and enjoy a more naturalistic swimming environment, especially if your home is near the sea, fiberglass will be your only option.
Fastest Installation
Fiberglass pools have fast installation times because fiberglass pool shells are built and tested in a manufacturing facility rather than being built and tested in your backyard. The average installation time for a gunite or vinyl lined pool is around 2 months from the beginning of the design process all the way to the finishing work. By contrast, a fiberglass pool can be totally completed in around 3 weeks or even less. This is a huge difference in the amount of time before you and your family can dip your toes in the water.
Fewer Recurring Costs in the Long Term
Upfront, the cost of a fiberglass pool can be higher than vinyl or gunite pools. However, the routine maintenance costs of both vinyl and gunite pools can start to add up. Gunite pools will need to be resurfaced in 7-10 years. Vinyl pools will need to have the vinyl liner replaced in 5-9 years.
By contrast, the gelcoat (the resin lining) of a fiberglass pool, which gives the pool its color and a luxuriously smooth feel, can last decades as long as the pool comes from a quality manufacturer and the pool is regularly maintained with minimal use of harsh chemicals that could degrade the resin lining.
Increased Home Value
Fiberglass pools are seen as a more high-end and desirable option over other pool material types. By including this more permanent pool in your backyard design, your home will have a valuable asset and you can leverage this in case you ever decide to sell. Though gunite and vinyl lined pools may be an asset as well, your home’s potential buyers will certainly be looking at the age of the pool and whether it’s due for a new lining or resurfacing.
Lesser Need for Harsh Chemicals and Easier Cleaning
Fiberglass pools are much better at deterring growth of mold and algae, which means you don’t have to treat the pool with harsh chemicals in order to keep the water sparkling clean. The resin surface of the pool basin is non-porous, so mold and algae have fewer opportunities to establish themselves even if the pool isn’t in regular use.
Of course, regular maintenance is necessary with any pool, but compared to gunite pools, you’ll be able to spend a lot more time swimming or hanging out by the pool and less time cleaning the pool.
Long-Lasting Durability
You can rely on a fiberglass pool for several decades of backyard fun and relaxation. Fiberglass is a stress-treated material that does not deteriorate with contact with water. It’s also incredibly flexible despite the seemingly rigid frame and this comes in handy throughout the change in seasons and the freeze-thaw cycle that can wreak havoc on a rigid gunite pool which will not flex at all, and a vinyl pool which can become brittle in a deep freeze and then crack easily.
A fiberglass pool will hold up against the stresses of the natural world as well as the rigorous demands of everyday backyard fun.
Built-In Amenities
With a gunite or vinyl pool, you can of course get any size or shape pool you like and add any amenities and features you want such as a Baja shelf or underwater seats. But any added features will add to the installation cost since they’re not part of the basic shell. Fiberglass pools come in dozens of styles that give you the size, shape, and amenities that will make your backyard swimming experience a great one.
Quality manufacturers will offer pool styles that feature what their customers want the most. If you want a pool for a small backyard but don’t want to sacrifice on features, you’re covered. If you want a lap pool or a kidney-shaped soaking pool, a big pool or a small one, you can find a model with a built-in spa, generous steps, and other amenities that amp up the fun.
Recycling Unused Plastic and Glass
Fiberglass pools are often constructed of both recycled plastics and recycled glass. These materials, which may otherwise end up in a landfill or worse, in the ocean, will be shredded, heated, treated, and pressed into the shell of a gorgeous new fiberglass pool.
This gives recyclable materials a second life: one that will provide the basis for your family’s backyard fun and relaxation. And did you know the pool shell can even be recycled at the end of its decades-long lifespan? This makes fiberglass pools the most eco-friendly option for inground pools.
Taking It With You
It may surprise you, but a fiberglass pool can actually move with you to wherever you’re going next! If you’re in love with the model installed and it’s like-new, there’s no need to start from scratch in the new home and incur the cost of purchasing a new pool. Just as the pool was installed, it can be removed and transported to your new home. Other than excavation and installation costs, you’ll save many thousands on the cost of a new pool.
A Smooth Finish
The gelcoat that lines a fiberglass pool is smooth and feels great on bare feet. It also won’t snag delicate swimsuit fabrics. That means no more scraping knees and elbows on rough concrete. And best of all, this gelcoat is non-slip for safety.
What are the Drawbacks of a Fiberglass Pool?
So far you’re probably thinking that fiberglass is the perfect option for a quality inground pool. We think so. But to be fair, let’s check out the drawbacks, since no material is perfect in every way.
Just like there are some amazing benefits to a fiberglass pool, there are also a few drawbacks you’ll want to consider. In the spirit of learning the full picture before you make any permanent decisions, let’s take a look at the drawbacks of a fiberglass pool:
A Gelcoat Can’t Be Replaced Onsite
Fiberglass pools are incredibly tough and durable, but there is a limit to their lifespan. Most fiberglass pool shells will last around 30 years. During the manufacturing process, a gelcoat will be applied to the shell. It has to be applied in a controlled facility to ensure no contaminants get between the gelcoat and the shell. This means that you can apply an aftermarket finish to the gelcoat should it be slightly damaged, but the gelcoat itself cannot be reapplied onsite. Still, with a lifespan of 30 years under normal circumstances, recoating the pool shouldn’t be an issue anyway.
Higher Initial Cost
Like with most things, you pay for convenience. Fiberglass pools are convenient in their installation and extremely long-lasting, but the upfront cost is higher than with a gunite or vinyl pool which are built entirely onsite. A premade fiberglass pool shell is more expensive from the beginning simply because it’s already a finished product that has been thoroughly tested to ensure quality. In the end, a fiberglass pool is a smart investment since it can last for up to 30 years.
You May Not Be Able to Get Exactly What You Want
Fiberglass pools are available in many incredible models — some pool installers will offer upwards of seventy models, but there are some limitations. Basically you only have the catalog designs to choose from and you may not be able to find the perfect mix of size, shape, and built-in features (thanks to most reputable manufacturers offering many dozens of models, it’s rare to walk away wishing for a pool that checks all the boxes, but it can happen. You may find a company that makes custom fiberglass designs, but this will most definitely be a more involved, longer, and costlier process.
For a completely original pool design, you will likely be drawn to vinyl lined or gunite pools instead. Still, fiberglass pool manufacturers have taken into account what people want and most homeowners will be able to find a model that suits their practical and aesthetic needs very nicely.
Limited Pool Sizes
Fiberglass pools can be built to a range of incredible designs that cover all types of swimming preferences, but there is one crucial limit to keep in mind. Fiberglass pool shells are constructed in a manufacturing facility and they need to be transported to your home. This means that a single fiberglass pool shell needs to be able to fit on the bed of a truck on a standard road that’s 16 feet wide. Though this is still a fairly large swimming basin, it limits the size of your fiberglass pool to 16 feet wide. If you’re going for a huge pool, fiberglass may not be the choice for you.
Repairs May Stand Out Visually
Fiberglass pools are tough. They will stand up against all sorts of stresses, both natural and accidental. On the rare occasion that damage occurs, it is often possible to repair a gash or crack in the fiberglass shell. The drawback of this is that the newly repaired area of the shell will have a different shade than the original fiberglass. This may appear like a scar for a few seasons before eventually blending in. A fresh gelcoat patch applied on site can return the integrity of a fiberglass pool shell but it may cause a minor distraction in your field of view.
The Right Chemicals Must Be Used
All pools need weekly testing to ensure the right pH balance. Fiberglass pools can handle a wide variety of chemical mixes in freshwater and they are suitable for saltwater use if you prefer to minimize the use of pool chemicals. However, you want to be sure to use pool chemicals that won’t harm the gelcoat, which cannot be replaced on site.
The Possibility of Osmotic Blisters
As durable as they are, fiberglass pools have the possibility of developing osmotic blisters over time. An osmotic blister is a minor imperfection that happens during the application of the gelcoat during the build of the fiberglass pool shell. It’s a result of incredibly small debris getting trapped between the shell structure and the gelcoat (and the reason why gelcoats cannot be reapplied on site). While these osmotic blisters won’t compromise the integrity of the fiberglass pool shell, they may become unsightly.
After weighing the pros and cons, most homeowners still choose fiberglass. Let’s answer a few more questions that will help you decide whether a fiberglass pool is really for you.
Can You Build Your Own Fiberglass Pool?
Not really. You may have come across a few websites or even heard through the grapevine that it’s possible to build your own fiberglass pool. While this may be true for some homeowners, building a fiberglass pool is definitely far from the small scale of a DIY project. Fiberglass pools should be built by trusted manufacturers in a controlled facility and installed by experienced professionals. You should definitely leave it to the pros for this one since a fiberglass pool is close to a lifetime investment.
Can Fiberglass Pools Be Heated?
Absolutely! It’s completely possible to install a heating element in your fiberglass pool. Not only are fiberglass pools compatible with heating systems, it’s actually a wonderful and often necessary addition. Fortunately, your pool heating bills will be low when compared to gunite or vinyl pools. The fiberglass shell provides a great deal of insulation which greatly reduces the amount of heat lost to the surrounding soil or the air above. Not only will the water in your fiberglass pool remain warmer for longer, it will also cost far less to keep the water at a pleasant temperature than other types of pools.
Do Fiberglass Pools Crack Easily?
Not really. They don’t crack easily, but there can sometimes be a possibility of fiberglass pools developing small hairline fractures in the gelcoat layer. This is more a sign of the gelcoat being applied too thinly during the manufacturing process, though this is extremely rare if you go with a pool built by a reputable manufacturer. Simply keep an eye on any cracks and if they start to get any bigger, it might be time to schedule an inspection. It’s highly unlikely, but if you ever notice deep cracks in the shell of your pool it’s time to call a pool specialist immediately. Sealant can be applied to prevent water and debris infiltration between the gelcoat and the shell.
How Deep Can a Fiberglass Pool Be?
On average, a fiberglass pool will be around four to six feet deep. The fiberglass pool shell is incredibly strong, but there is a limit to how much water it can support. Below six feet of water, the fiberglass shell may be compromised by the immense amount of pressure from the water above. Fiberglass pools are not designed to be any deeper than six feet so if you want a deeper pool, then a gunite pool would be your best bet. For most people, though, six feet is plenty deep enough for backyard games of water polo, Marco Polo, lap swimming, or a leisurely float.
Can You Put Saltwater In A Fiberglass Pool?
Definitely! In fact, fiberglass pools are the only types of pool that can support a saltwater system. Many homeowners have decided to forego the need for harsh pool chemicals and opt for a saltwater system. A certain concentration of salt in the pool water will inhibit mold and algae growth while significantly reducing the need for chlorine and other chemicals. Saltwater does corrode many strong materials, however, and fiberglass is the only pool material that won’t be affected over time.
Are Fiberglass Pools Worth It?
Absolutely! At this point, you’re already fairly far along in deciding whether or not to install a fiberglass pool in your backyard. There are various comparisons that need to be made concerning the pool that best meets your needs.
Remember that in the short term, a fiberglass pool may be more expensive compared to gunite or vinyl, but the costs will be significantly lower in the long run. Make sure you review our lists of pros and cons in this article so you can determine if a fiberglass pool is right for your backyard.
How Long Do Fiberglass Pools Last?
When you add a fiberglass pool to your backyard, you can expect that it will last for up to 30 years or even more as long as it's taken care of regularly. In many cases, vinyl lined and gunite pools will only last around 10 years before needing complete resurfacing, which can cost over ten thousand dollars. Since fiberglass pools don’t need any regular maintenance to the shell itself, you can expect a fiberglass pool to last up to 3 times as long as other types of pools.
Who Makes the Best Fiberglass Pools?
One of the most important steps in your pool installation process is the company you decide to go with. In most cases, pool installation companies work with a manufacturer exclusively. Let’s go over some of the most well known and best fiberglass pool manufacturers:
Alaglas Pools: Alaglas Pools is known within the pool industry as one of the favorite fiberglass pool producers. There are four layers in the shell of each fiberglass pool from Alaglas, all working together to build an incredibly strong and durable swimming structure.
Latham Pools: Latham Pools is the largest fiberglass pool producer in the world and was formed with the recent consolidation of Blue Hawaiian Fiberglass Pools, Trilogy Pools, and Viking Pools. They have the widest reach of any fiberglass pool producer and the biggest catalog of incredible designs!
Sun Pools: Sun Pools, Inc. has created a high level of elegance and innovation in fiberglass pools. They have a huge range of models that build your pool into a true hub of all the fun activities you and your family experience. They cover most of the US with their amazing pool designs!
Leisure Pools: Installed on a steel frame and constructed from durable fiberglass with a tensile strength of 21,000 pounds per square inch (these are the same materials that are used in the wings of a Boeing 777).
If you’re ready to make your backyard a true haven for summer fun, now is the time to start planning, designing, and scheduling your pool installation with a reputable installer.