If you’re thinking of getting an outdoor pool, you’ll know the three main types of pools: concrete, fiberglass, and vinyl.
If your heart is set on a concrete pool, then you’ve certainly come across the term gunite. Gunite-built pools are sturdy structures meant to stand the test of time throughout everything the seasons throw at them.
If you have no clue what gunite is or how it differs from regular concrete, you’ve come to the right place. Learn all about gunite, how it gets used in pool making, how long it lasts, and what maintenance is required after the construction is said and done.
What is Gunite?
Gunite is a special process to make concrete structures quickly and without much hassle. Gunite doesn’t use molds like other concrete structures. Instead, it’s sprayed directly onto a receiving surface and bonds with it, making it perfect for pools.
Concrete is thousands of years old and has been historically used with molds or removable forms. Concrete structures last the test of time and were invented by the Romans. The Colosseum stands as a testament to the longevity of concrete.
The gunite process was coined by a taxidermist named Carl Akeley to fix Chicago’s Field Columbian Museum. Gunite got trademarked in 1909 in North Carolina by Allentown Equipment, one of the oldest gunite equipment manufacturers.
What’s Gunite Made Of?
Gunite is concrete and uses a mixture of dry concrete powder, sand, small particles such as crushed stone or gravel to act as a binder, and water sprayed on with a hose.
Concrete hasn’t changed much over the years, so the process for making concrete is still relatively the same. While there might be different types of concrete, they all use the same basic building blocks, lime or silicate powder, and water.
The Gunite Process
Gunite is a process of mixing sand or gravel and concrete and applying moisture to it directly before it’s plastered on a receiving surface. The method uses an air compressor to shoot it out at high speeds. That’s why it’s termed “gun” -ite.
Unlike other concrete processes, the gunite process is a dry mix of concrete.
This means that the dry ingredients get mixed before shooting through a hose, with water being mixed in at the nozzle right before it gets released. As a result, the mixture is not fully incorporated when it comes out of the hose. Instead, it is the impact of this mixture on the receiving surface that completes the mixing process.
A skilled nozzleman should handle this process as you need to get the timing and mixture amounts just right for it to turn out as it should. If it isn’t, the concrete mix could not adhere to the receiving surface because it’s too dry or not cure properly because it’s too wet.
About Gunite Pools
Gunite-built pools became popular after World War II as returning soldiers looked for more creature comforts and moved their families into newer, suburban neighborhoods. However, since many wanted custom-built pools, construction companies found that using a form to build pools was time-consuming and ineffective.
Pools using the gunite method were more cost-effective. In addition, they didn’t use as much heavy equipment, were attractive, and were very customizable.
How They’re Made
Since gunite pools are all inground, the first thing that needs to happen is digging a hole in roughly the shape, depth, and size you’d like your pool to be. With this process, you can have as crazy a shape you want.
When the hole is finished, workers will outfit it with plumbing for your pool. They’ll also reinforce the edges and bottom of your pool with rebar so the concrete will last longer and issues won’t arise if the ground erodes around your pool.
Shotcrete is another type of sprayable concrete but requires a one-and-done approach, while gunite can get done in stages, so the construction workers can take their time in getting it right rather than rushing to finish it.
Most types of concrete shouldn’t be applied at different times, causing cracking, structural flaws, and can make your pool look unappealing when the whole process is over.
Gunite gets sprayed at such high pressure, and with the water added at the very last second, seasoned and knowledgeable nozzlemen can spray days apart and still have it looking perfect.
As your swimming pool cures, construction companies will install the coping that you chose. Coping is what construction companies use to cap the pool edge, such as concrete, natural stone, or brick. With coping, your pool has a seamless flow into the patio surrounding it, which construction companies may expand as well if you’ve added it on.
If you’ve contracted them to add accessories to your pool area, this is the time they’ll install them. Accessories can include fencing, retaining walls, landscaping, or extra water features like a waterfall.
After the curing process, your pool will get a finishing material such as a liner or tile to help give your swimming pool a clean look with no rough edges like the plain concrete would. This layer also protects the concrete, making it last longer.
The Curing Process
All concrete has to cure for a set amount of time to be strong and durable enough to stand the test of time. The length of curing time has many different factors, including:
- Concrete mixture proportions
- Specified strength of the concrete
- Size and shape of your pool
- Weather conditions
- Future exposure conditions
Since pools are outside structures, the curing time is dependent on the weather, which is why construction companies give a generous 28 days for pools to cure to make sure everything is set in place.
Even then, cracks can appear if the weather conditions are terrible for the season, which is why it’s best to build your pool in the fall. The ground is drier, and the weather tends to be more stable.
Adding extra layers once the curing process begins will extend the curing time of the concrete. The additional layers may also cause structural issues because the layers underneath don’t cure properly.
How Long Do Gunite Pools Take to Make
Once construction workers are on-site and working, your pool should be ready to go within three to six months. If you contract them out in the fall, you should be ready to go when summer hits.
However, be aware that there might be quite a waitlist as pool construction is considered a specialty, so not any construction company can complete it. With the economy where it’s at today, you could be waiting months to even a good year before you can get your pool.
What do Gunite Pools Cost?
The cost of a gunite-built pool is very subjective since they are so customizable. The economy also plays a massive part in the price of everything, from the cost of materials to labor.
For a standard pool, you don’t want to go under $50,000. If a company prices below that, it’s a red flag, and you should get a couple more estimates before taking the plunge.
If you want many bells and whistles, or where the pool is going to sit needs extensive landscaping, that price could be well into the six-figure mark.
Maintaining a Gunite Pool
Since water and weather are some of the most corrosive elements to concrete, your gunite-built pool has an average lifespan of 10-15 years. In those years, your pool needs regular maintenance, so it lasts as long as possible.
Your pool maintenance should start every year when the weather starts warming up and the cold seems to be over. Ensure you have everything you need to fill and maintain your pool for that year and have a checklist ready of the chemicals you need so you don’t forget.
Make sure you regularly clear debris such as leaves, dead bugs, and the like to avoid issues with algae growth or poor water circulation. The buildup will also accumulate on the walls, so invest in an automatic cleaner or take a manual scrubber to the walls and bottom of your pool every few weeks.
Don’t forget to clean the filter so your pool water stays clean and pleasant to swim in. Much like any filter, it helps keep grime and unwanted particles away from your pool but can become ineffective if you leave it uncleaned for too long.
You’ll also need to test the chemical level of your water frequently, so your water stays clean but doesn’t hurt the people swimming in the water. Maintaining the correct water level and having a working pump with no leaks is essential to keeping your gunite pool clean.
You’ll need to winterize your concrete pool at the end of the swimming season if you don’t plan on draining it completely to avoid cracking and algae buildup. You will have to drain to appropriate levels and continue using chemicals in your pool and draining the pool hoses, cleaning the pump and filter, and covering the pool.
Pools are a lot of work, but thankfully there are plenty of pool service companies out there that can help you out.
Gunite pools are excellent investments if you want a customizable and attractive pool. However, just like other pools, it takes time for construction companies to complete them, and they require maintenance every year.
They add value to your home and enrich you and your family’s lives by giving you a place to relax and enjoy the summer months without going to a public pool. In three to six months, you could be swimming around in your private pool.