Closing your Pool for Winter

Even though you do not use your pool as often during the winter, it is still very important to look after it to enable the following summer to be a trouble-free one.

By preparing your swimming pool for winter in the correct way, you can significantly reduce the chances of algae growing and increase the chances of your pool remaining clean for the following summer season.

That means when it rolls around to next year and the sun starts shining, you can reopen your pool faster without having to deal with unexpected issues which could put your pool plans in jeopardy.

How to close your in-ground pool for winter

Closing down a swimming pool for winter is part of your annual pool maintenance so that, come next summer, you’ll be able to start using your pool again with minimal risk of issues.

To achieve this, all you need to do is follow these simple guidelines:

  1. Backwash the filter and clean the strainer.
  2. Check the pH is between 7.2 and 7.6 and use sodium bisulphate (to lower pH) and sodium carbonate (to increase the pH) to adjust if necessary.
  3. Using Calcium Hypochlorite, boost the chlorine level to remove any algae that maybe present in the pool.
  4. To prevent algae from growing add winterising algaecide.
  5. Turn on the circulation to disperse the solution through the water for a period of 24 hours.
  6. Reduce the water level to just below the skimmers. This is to allow for any extra water that enters the pool, ie rainfall, therefore preventing it from overflowing.
    WARNING: Do not lower the level too much especially if the water table is high as this could cause structural damage to the pool shell.
  7. To protect any exposed metal surfaces, drain the water from the pump(s), filter(s), heater and pipework.
  8. Leave any valves above the water level open. Any below should be closed to protect from frost damage.
  9. Switch off the electricity supply to the system.
  10. Cover the pool with a heavy-duty winter pool cover.
  11. Check the appearance of the water, and the chlorine/pH levels occasionally during the winter.

These instructions on how to prepare a pool for winter are specifically aimed at in-ground pools or for hard sided above-ground pools. 

For above-ground pools, it is often easiest to empty them and pack them away for the winter. When packing it away make sure that it is dry and packed away neatly in a dry place. This will avoid the pool from developing any unwanted algae or otherwise due to excess moisture.

When summertime does come back around, we also have a handy guide for reopening your pool for summer. This covers all the steps needed to start enjoying your pool again, made much simpler if you’ve correctly closed it over the wintertime.

All dosing rates can be found on the instructions of each product.