How Soon Can You Swim After Plastering a Pool?

Plastering your pool makes it look more aesthetically pleasing and can extend the structure’s lifespan. It creates a watertight seal for in-ground pools that prevents leaks from forming. However, plastering your pool can also cause a significant issue: you will have to wait for some time after you plaster your pool before you can start swimming.

You can swim 48 hours after plastering your pool. However, experts recommend waiting at least 72 hours, as this will give your filtration equipment enough time to clean your pool properly. The 48-hour minimum allows your plaster to set enough that you won’t leave any marks on it while swimming.

If you’re hoping to learn more about swimming after plastering your pool, you’re in the right place. I’ll explain in further detail why you should wait to swim for a couple of days after plastering.

you can swim within 48 hours after plastering your pool
Worker Smoothing Wet Pool Plaster With Trowel.

Why You Should Wait Before Swimming in a Newly Plastered Pool

There are a few key reasons you should wait to swim in a pool once it has been plastered. Let’s take a look at these below.

You Need To Fill the Pool With Water

You cannot plaster a pool already filled with water, which means you have to completely drain it before applying any plaster. Once the pool is plastered, you can turn on the water immediately and start filling it up – but filling a pool takes time.

The amount of water you will need to fill your pool completely will depend on numerous factors, including your pool’s depth and dimensions. On average, however, residential pools contain anywhere between 10,800 gallons (49097.77 L) to 30,000 gallons (136382.7 L) of water.

If you’re filling your pool with a garden hose, it can take approximately 20-54 hours to fill it completely (this estimation is based on a 9-hour average to fill a 5000-gallon or 22730.45 L pool). For obvious safety reasons, you should not swim in the pool until it is filled.

The Filtration Equipment Needs To Clean the Pool

While pool plaster needs to be submerged under water to be effective at forming a watertight seal, it will also affect the makeup of the water in your pool immediately after it has been installed. When the plaster is submerged for the first time, calcium hydroxide from the plaster leaches into your pool water. 

This causes an increase in the pH of your pool and can cause the water to become cloudy. Swimming in murky water carries health and safety risks and should be avoided whenever possible.

Luckily, this leaching is a limited issue. Once the calcium hydroxide fully leaches for the first time, there shouldn’t be any similar issues in the future. However, you will still need to solve the problem the first time around. 

The solution to the issue of calcium hydroxide leakage is to let your pool filtration equipment do its job. Ideally, you should run your filtration equipment should run for at least 72 hours non-stop before your pool is fully clear of the leached chemicals. Once your filtration equipment is done working, you will then need to adjust the pH and alkalinity levels to the optimum and also adjust the calcium hardness if necessary. 

So, while you can start swimming within 48 hours of plastering your pool (assuming you can fill the pool with water by then), there’s a risk that your filtration equipment may not have managed to filter out all the calcium hydroxide. Waiting 72 hours gives you additional peace of mind.

Swimming Can Cause Damage to the Plaster

While plaster takes 7-10 days to cure properly, it dries relatively well within 24 hours. However, during those 24 hours, it is susceptible to aesthetic damage. 

Essentially, even if you have a small pool that you can fill in a few hours, swimming in the first 24 hours after plastering can result in you leaving marks on your fresh plaster. While this won’t necessarily damage the structural integrity of the plaster, it will affect the aesthetics.

pH Levels May Require Adjustment

Before you get in your pool for the first time, you should make sure that the water’s pH is at optimum levels. Ideally, your pool’s pH should be between 7 and 7.6

If the pH levels are higher than recommended, swimming in the pool may result in skin issues, such as rashes. On the other hand, if the pH is lower than 7, you will experience irritation in your eyes. 

There are a few methods of starting up your pool for the first time, and all of them involve pH concerns:

Bicarb Startup

This method essentially involves adding sodium bicarbonate (better known as baking soda) to your pool in large quantities. This method significantly reduces and can even eliminate calcium hydroxide run-off from newly applied plaster. However, the trade-off is that this can increase the pool’s pH to about 8-8.3, which is higher than ideal.

Acid Startup

Also known as a hot start, this method essentially involves adding a significant amount of acid to your pool water. This method aims to lower the pool pH to about 4.3. There are two advantages to this: it creates an evenly exposed finish, bettering the pool aesthetics, and it also “burns” off the plaster dust, which means you don’t have to worry about calcium hydroxide run-off. 

However, as with the bicarb startup, this startup method creates issues with the pool’s pH levels. In this case, it is significantly lower than the ideal.

You can bring your pH levels back in balance by adding soda ash to neutralize the effect of the acid. However, you should avoid entering your pool until you balance your pH levels

While many people prefer acid startups for the etching look it offers a pool, you will also need to give the acid time to work properly, after which you will need to take the time to ensure it is fully neutralized. This can often take longer than the 48-72 hour window discussed above, which also means you’ll need to wait a few days more before you can start swimming in your pool.

Regular Startup

The regular startup procedure takes significantly longer than either acid or bicarb startups. In fact, it involves 28 days of constant maintenance, including checking your pool’s pH and alkalinity levels and brushing it daily. 

In this method, you will have to pay close attention to the pH and alkalinity levels during the first two days after filling the pool, as well as the calcium hardness level on the second day. This is because these parameters can fluctuate significantly immediately after your pool is filled, and they must be balanced before you can swim in the pool safely. 

While you will still have to monitor these parameters (and others) for the rest of the 28-day startup period, there is a lower risk that the levels will fluctuate and need to be adjusted. For health and safety reasons, it’s best to avoid jumping into the pool before the pH levels are balanced, which can take about 2 days with this startup method.

Worker Wearing Sponges On Shoes Smoothing Wet Pool Plaster With Trowel.

Final Thoughts

You should wait 48 hours before swimming in a newly plastered pool, though we recommend waiting at least 72 hours to give your filtration equipment time to work properly. However, depending on your pool startup method, you may need to wait a few days longer.