So you are ready to renovate your pool or build the pool of your dreams for the first time. After significant research, you have decided that the best pool for you is a concrete pool. It may take a little extra work to maintain, but a concrete pool is definitely state of the art. Concrete pools can be completely customized. You can pour, shoot, or install concrete into any shape you could possibly imagine. And concrete is the only way to get the most classic swimming pool look. So your mind is made up. You’re ready to install a concrete pool. There’s just one hitch. You don’t know how to build a concrete pool.
The easy answer is that you build a concrete pool by paying someone to do it for you. We actually like that answer a lot, since the construction work that goes into building or renovating a concrete pool requires a variety of high-level skills. But we still want you to know how your pool will be built, even if someone else is doing the work. So here is The Pool Butler’s complete review of how to build a concrete pool.
What Is a Concrete Pool Made Of?
So let’s clear up one common misconception right away. There is concrete, and there is cement, and they are not the same thing. Although we often use the terms interchangeably, cement is an ingredient in concrete and is rarely used alone. Cement is a powdery binder that can be mixed with water to make mortar or with sand, gravel, and water to make concrete. The cement, when combined with water, holds the sand and gravel together, and all together they form a very hard substance.
But concrete alone would not make a very useful swimming pool. Concrete is very hard to crush—it can withstand 3,500 psi or more—but it is brittle and will crack if pushed or pulled. To give concrete more tensile strength, it is poured over a network of reinforcing steel bars, commonly known as rebar.
Finally, the interior of a concrete pool has to be covered in something more waterproof and visually appealing than the plain concrete. That surface could be tile, plaster, waterproof paint, or other specialty materials.
Step 1: Design
Concrete pools are completely customizable. Unlike a fiberglass or vinyl pool that comes with a prebuilt design, a concrete pool can be any shape or size. To determine how to build or renovate the pool, you need to start with a detailed design for the builders to follow. You will have to work with a pool designer to do this properly; a sketch on a napkin won’t cut it. Like any architectural design, you will start with a general idea of what you want to see, but you won’t be done until you have a detailed blueprint that tells the construction workers precisely what to do. This should be a fun process as you get to turn your dreams into a concrete plan (excuse the pun).
Step 2: Permitting
This is the least fun and exciting part of the construction process, but one of the most important. Unless you really live in the middle of nowhere, chances are that your city or county will require a residential building permit before you build your pool. The approval process can vary significantly from one municipality to the next. In some places, you may submit your plans and receive your permit in a week or two. In other places, you may need multiple approvals, appearances at city or county planning meetings, and official sign-offs from engineers and city officials. However, even if this takes time, it is a critical part of the process.
It is never a good idea to proceed with a building project without a permit. You could face steep fines or even be required to remove the illegal project, i.e., destroy your new pool. The permitting process also helps ensure that your pool is being built safely and in compliance with industry standards.
Step 3: Excavation
This is where things get exciting. Using some heavy machinery, your builder will start ripping up your poor backyard to make a hole big enough for your new swimming pool. This step could be done in just a day or two if everything goes smoothly. Possible hiccups include power lines, trees, or other hazards that make it hard for heavy machinery to access the site of your future pool. Be prepared for a pretty big mess at this point. There’s going to be a lot of dirt flying around, and it will need to go somewhere. Sometimes, the dirt can be moved to another part of your property and used for a separate landscaping project. But if you don’t have anywhere to put the dirt, you can have it carted away and disposed of elsewhere.
Step 4: Plumbing, Electrical, and Steel
Once you have a giant hole in roughly the shape of your future pool, it’s time to start putting things in it. The main component you will have to install in your freshly dug pit is all the steel that will form the rebar for your concrete. As we mentioned above, concrete alone is susceptible to cracking under tension. To increase its tensile strength, almost all concrete construction is done over a web of reinforcing steel bars, commonly known as rebar. In this step, builders will install all of the rebar, and the shape of your pool will start to come together.
Before the concrete is added, your builders will also have to install the plumbing and electrical components of your pool. This includes your pool’s full circulatory system, including drains, pumps, returns, and any additional water features. It also includes all of the electrical for lights or other features. Depending on the size and complexity of your pool, this could take two weeks or more.
Step 5: Adding the Concrete
This is where the concrete pool is really built. There are two main methods for applying the concrete. The first is to frame up the walls and floor of the pool with wooden framing and to pour the concrete into the frame. Once the concrete cures, the frame is removed and you have your concrete pool. The other common method is to use a power sprayer to apply gunite or shotcrete. Gunite is put into the sprayer as a powder and mixed with water in the sprayer, while shotcrete is put into the sprayer wet. The application process is the same for both materials. The builders spray the concrete in place and then finish it off by hand with trowels to get a smooth surface.
Once the concrete is sprayed or poured, it needs to cure. The concrete can cure for as little as one week, but often builders will wait 4 weeks for the most complete curing. Curing is not the same thing as drying. As concrete cures, it hardens through chemical reactions, but you actually need to add water for the best results. During the curing period, you will need to spray down the walls and floor of your pool daily. Usually, this part of the process is left up to you, the pool owner, to take care of.
After the concrete cures, there will be extra space in the hole that was excavated for the pool. The area outside the walls is refilled with soil, called backfill, and compacted as much as possible.
Step 6: Surfacing and Coping
In this step, you apply the final surface to your pool. When it’s done, the pool will really start to look like your original design. There are many options for how to surface the inside of your pool. The simplest method is to apply waterproof paint. A more common approach is to use plaster. Plaster is relatively cheap and gives the most classic pool look. However, it can leave a rough surface. After 5-10 years the pool will need to be resurfaced with new plaster.
Sometimes, plaster can be mixed with decorative materials such as pebble, quartz, or glass beads to form an aggregate. After the aggregate is applied, the top layer of plaster is wiped off to reveal the decorative material. It can be left as is for a bumpy surface, or polished smooth. A quartz aggregate surface will usually last 7-12 years, while a pebble aggregate can last 10-20 years.
The most expensive option for surfacing a pool is to use tile. The price depends on the cost of the tile you use. Ceramic tile is the cheapest, stone is more expensive, and glass tile can get very expensive. However, a tiled pool will also last the longest.
If you use a plaster or aggregate surface, you should install tile around the pool at the waterline to avoid a nasty water ring.
The same contractors who install your tile, either for the whole pool or just the waterline, will probably also install your coping. Coping is the tile around the lip of the pool, where your patio meets the pool wall.
Step 7: Patio, Landscaping, Fencing, and Customizations
After the pool itself is built, you will need to install the appropriate landscaping around it. At the very least, you will need a patio area around the pool. Depending on your designs and your budget, you could get as creative as you like with your patio, landscaping, and customizations. Customizations include waterfalls, diving boards, waterslides, and anything else you might dream up. Obviously, the time and cost involved depend on how big you dream.
One of the most critical parts of your pool is not actually a component of the pool, it is your fencing. Many states require fencing around a pool by law. But even if your state doesn’t, putting a fence around your pool to prevent accidental falls is crucial. You can learn more about secure pool fencing and safety in general in this article.
Step 8: Water and Startup
Once everything is in place, you can fill your pool. If water is relatively cheap where you live, you can just use a garden hose to fill up the pool. Be prepared for it to take a while. If water is expensive or your pool is really large, you can have water brought in by truck. This is much faster.
Once the pool is filled, it can take 10 days before it is ready to swim in. For 10 days, make sure to brush the pool and balance the water daily. Wait at least 48 hours before adding chlorine. If your pool is surfaced with plaster, the daily brushing will remove any leftover plaster dust, so don’t run a pool heater until you are sure all the dust is gone.
Installing a concrete pool can be expensive and time-consuming. On average, the installation will take 8 to 12 weeks, but it could take much longer. The average cost is about $60,000, with a bare minimum of about half that. Of course, with the high level of customization concrete pools offer, the time and money you could spend building your dream are really unlimited.
Once your pool is built, it will need to be maintained. Contact The Pool Butler to learn how we can help keep your new pool in like-new condition for years to come.