As winter approaches, you’ll need to winterize your in-ground pool to protect it from the cold season’s wear and tear. Closing your pool properly can prevent costly damage and ensure a smooth reopening come spring. This simple guide discusses the proper way to close an in-ground pool for winter. 

Pool party

When is the best time to close my in-ground pool for the winter? 

When closing an in-ground pool, timing is everything. Generally, the best time to close an in-ground pool is when the water temperature consistently falls below 65°F (15°C). The professional pool buiilders at Liquid Luxury Pools explain that at this temperature, algae and other organisms are less likely to grow, which helps maintain a cleaner pool over the winter. 

If you winterize the pool too early, the water could remain warm enough for algae growth, requiring extra chemicals. On the other hand, waiting too long is a risk for freezing temperatures that may damage pool components. Keep an eye on the forecast in late fall to choose the ideal time for winterization. 

Are there any safety precautions I should take when closing my pool? 

Safety is essential when winterizing an in-ground pool. Here are things to keep in mind, according to the professional pool builders at Liquid Luxury Pools: 

  • Shut off all pool electrical components, including pumps and heaters, to avoid potential hazards. 
  • Drain water from pool equipment. If water is left inside, freeze-thaw cycles can cause damage; drain hoses, pumps and filters. 
  • Wear gloves and safety goggles to prevent irritation or injury when handling pool chemicals. 
  • Children and pets should not be allowed in the area to prevent accidents.  

How do I shock my pool before closing? 

The purpose of shocking your pool before closing is to clear out any lingering bacteria or algae. To avoid mistakes, you must follow all the steps to close an in-ground pool. 

  1. Choose the right shock. If your pool uses chlorine, use a chlorine-based shock; and for pools that use alternative sanitizers, use a non-chlorine shock. 
  2. Measure carefully. Read the shock treatment instructions to add the correct amount.  
  3. Gather safety gear and supplies. You will need a pool water test kit, pool shock, mask, chemical-resistant gloves and closed shoes.  
  4. Apply shock treatment. Pour the shock treatment around the pool’s perimeter and allow it to circulate for at least 24 hours. Don’t add chlorine shock and algaecide together.  
  5. Wait for chlorine levels to stabilize. After 24 hours, test the water to ensure the chlorine level has returned to 1–3 ppm before covering the pool. 

What chemicals should I use to balance the pool water? 

Your pool winterizing kit should contain the following chemicals: 

  • Alkalinity increaser. Adjust total alkalinity to a range of 80–120 ppm. 
  • pH adjuster. Adjust pH to a level between 7.2 and 7.6; the correct pH range minimizes the chances of algae growth and protects pool surfaces. 
  • Calcium hardness increaser. If calcium hardness is too low, add a calcium hardness increaser to achieve 200–400 ppm levels. 
  • Algaecide. A long-lasting algaecide prevents algae from growing during the winter; pour it around the pool’s perimeter. 
  • Metal sequestrant. If your pool water contains metals like iron or copper, add a metal sequestrant to prevent staining. 

What type of pool cover should I use? 

A pool cover protects your winterized pool from debris, harsh weather and unwanted entry. Here are the pool covers you can opt for: 

  • Solid covers. These heavy-duty covers keep out debris and sunlight, reducing algae growth and protecting the water from contaminants. However, they require a pump to remove accumulated water on top. 
  • Mesh covers. These lightweight and easy-to-install covers allow water to drain while keeping leaves and debris out. They don’t prevent algae growth as effectively as solid covers but are lower maintenance. 
  • Safety covers. These are designed to prevent accidental falls, so they are ideal for households with children or pets. They are available in both solid and mesh varieties. 

Summing it up 

Closing a swimming pool can be challenging if it’s your first time doing it. That’s why it is always advisable to consult professional pool builders to close your pool correctly. That way, you are assured your pool will be safe, protected and ready to enjoy again when the warmer weather returns.