How to Close Your Inground Pool for the Season

There are few things in life more pleasant than plunging into the pool on a hot summer afternoon. This experience is made all the more luxurious when you can enjoy it from the comfort of your own backyard. Having an inground pool at your home helps make the summer months truly special, but unless you are lucky enough to live somewhere with enviable year round sunshine, there will unfortunately come a time to pack away the swimwear and cover up the pool.

As winter rolls in and temperatures drop, the effort of properly closing your pool may seem way too much but trust me- it’s worth it! Taking the time to correctly follow the procedures I will lay out for you now will not only save you a small fortune, it will also make your life so much easier when summer comes back around and you are ready to dive in once again.


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To Cover, Or Not To Cover?
Closing your pool at the right time in the right way helps avoid build up of dirt, mold and algae collecting under the cover that can end up damaging vital parts of the pool’s system. This is not a cheap or easy fix and will certainly put a dampener on the first good swimming day when you can’t actually go into the pool.

If you choose not to cover the pool at all, you will be facing a fair bit of work to keep the water debris free and to make sure the chemical levels are kept safe and steady. These tedious tasks aren’t much fun at the best of times, never mind on frosty winter mornings when I’m sure you would much rather be cozy indoors with a cup of hot cocoa. If the time cost isn’t off putting enough, think of the monetary cost. Keeping your pool pump and water circulation systems running continuously when you can’t enjoy the benefits is a serious waste of money and can be easily avoided if you just follow the correct steps when the time is right.

So, When Is ‘The Right Time’?

Unfortunately there’s no one single day of the year when all pools must be covered. It will take a little attention and observation from you, as it depends entirely on the temperature of where you live. It’s a good idea to leave closing your pool as late as possible to minimize the length of time the water will stay covered- the shorter the time, the lesser the grime. Don’t even start to think about covering until the temperature outside is consistently below 65 degrees fahrenheit day to day. Until this happens, you can follow your usual care and treatment routine which will help the pool stay in good condition throughout winter. You can continue this treatment on any odd warm days you happen to have during the cold season, should you feel motivated to do so. When the temperature has officially dropped and the time has come to say ‘goodbye for now’, you can begin preparations by gathering all the necessary tools, gear and chemicals you will need to get started.

What You Will Need.

Covering your pool for winter is an important job, and there are some specific pieces of gear you will need to ensure the job is completed properly. The majority of these items are necessary equipment for all pool owners to have at one point or another so it will most likely be a case of finding items you already have in the garage or the garden shed rather than heading to the shop to buy them new. If you do turn out to be missing something, be sure you buy yourself a good quality product that will last, so next year you will already be good to go. Here is a rundown of what to get ready:

1. A good quality pool brush- I recommend using a brush with as much bristle coverage as possible to make it easier to clean in corners and other tricky spots.

2. A robotic cleaner or pool vacuum- Be sure to use a respected and well known brand with products that are known to be hardy, professional and reliable.

3. The WinterPill- This one you may not have already but it will really make a difference. You can buy it easily online and in big stores.

4. Tools to remove pool accessories- A standard tool kit should do the job.

5. An air compressor or shop-vac- You will need high quality power, so some people may choose to rent or hire a professional rather than buy, but if you are confident in your DIY skills, this is what you will need.

6. Skimmer plugs and winter pool plugs- You will probably have these already but if not, make sure they are compatible with your pool as they come in all sorts of varieties.

7. Winter pool cover- Not the same as a safety cover, so make sure you look out the right thing!

8. Winter pool cover pump- Having a high quality and dependable cover pump will save you a lot of hassle and effort in the long run.

Now For The Sciencey Part!

Some aspects of preparing your pool for winter can feel like one big science project, and may take you back to the days of bunsen burners in the classroom. It might sound like a bit of fun, but correctly balancing the chemicals is vital for maintaining your pool’s good condition through months of inactivity. For this reason, it’s important to be stocked up on everything you might need- this list covers all the bases:

1. Water test strips- You will need these to check the levels.

2. Sanitizer- Chlorine is a popular option.

3. PH Increaser / PH Decreaser- For balancing levels as needed.

4. Calcium hardness increaser- For example, calcium chloride.

5. Alkalinity increaser- This is extremely important as a lack of alkalinity in the water can harm your pool and anyone in it.

6. Algaecide- To help combat any attempts by algae to grow underneath your winter pool cover.

There are also a few optional extras you may want depending on your pool’s individual requirements:

1. Metal sequestrant- You only really need this if you are planning to remove any metal stains before covering, but it can also be useful for preventing staining over winter.

2. Cyanuric acid- Required if you are using unstabilized chlorine, if you are using stabilized chlorine then forget about this.

3. Antifreeze for pools- Antifreeze definitely has some benefits if where you live is prone to sub zero winter temperatures, but otherwise it’s not necessary.

4. Pool enzymes- Some people like to add this in but it is not an essential part of the process.

Now For The Main Event.

After gathering all the items you need, get ready to roll up your sleeves and get the show on the road. I would be lying if I said the whole process is a walk in the park- there are a lot of stages and you will need to put in quite a bit of care and attention to make sure everything is completed the way it should be. Luckily, like most things, it will get easier and faster each time you do it, and a few years down the line it will feel like second nature. For first timers, however, this step by step guide will help make the process clearer and more simple to follow- but it’s still going to take a bit of elbow grease to get the job done!

Step 1: Clean the pool.

Before adding any chemicals, it is essential for you to give your pool a really thorough clean. If you skip this step, you will be leaving a lot for the chemicals to fight against over winter, and most likely a lot more work for yourself when you open back up. Take your brush and scrub all along the sides and bottom of the pool, focusing extra attention on areas where dirt and grime gather the most, like in the corners or under any ledges. This is the most physically demanding part of the process, but by putting in the effort now you will minimize the amount of spores left sticking to the surfaces which can potentially grow into algae while the pool is covered. Buying a good quality brush developed specifically for this job by people who know the job will make it a lot less strenuous.
After brushing, send in your robotic cleaner or vacuum the bottom of the pool to clear any stray dirt or residue that may have escaped or fallen to the floor while you were brushing.

Step 2: Test and balance the water.

The fact that you won’t be swimming doesn’t mean the water doesn’t still need to be properly balanced. Don’t forget, your pool will be completely covered and your pump will be off for several months, so the better the condition you leave the water in now, the better the condition you are likely to find it in come spring. Use your test strips to check the current levels then add your PH balancers, alkaline, calcium chloride and sanitizer as needed. Take the time now to get it just right to save yourself hassle and money in the long run.

Step 3: Add winterizing chemicals.

Up until this point you will have noticed this is pretty much your average pool maintenance, but now is when it differs. It’s going to require a little extra help to keep everything looking good, so add in your WinterPill which will gradually dissolve, treating your pool consistently for a few months.
You are also going to want to add algaecide. One dose is enough in most cases but if your pool is prone to algae, you can add a second- although if you choose to do so, I would recommend to add metal sequestrant as algaecide contains copper and could potentially leave stains on the floor and walls. If you are opting to use enzymes add them now, and the same goes for antifreeze if you feel it’s necessary. Make sure it’s pool grade antifreeze as it is non toxic!

Step 4: Shock the pool.

No, I don’t mean take a break and go skinny dipping… It’s just the technical term for the next step of pool treatments.
There are two main considerations to make when shocking a pool. The first is timing. For pools outdoors in the sun, you need to shock either at night or very early morning otherwise the treatment will burn off before it takes effect. After sunset is a perfect time. You can apply the shock treatment, run your pool pump for 8 hours overnight and it will be ready in the morning for the next step.
The second is how much pool shock to use. Make sure you initially measure the amount needed for the size of your pool then depending on any already existing algae you may have just cleaned, you may want to double up.

Step 5: If freezing temperatures are a concern, lower the water level.

Unless you are at risk of frozen pipes, you can skip this step. If this is a reality for you, draining a little water can go a long way when it comes to avoiding damage, and ‘a little water’ is really all it takes. Exactly how much water depends on what type of liner you have. Your individual pool manufacturer might have specific instructions so check to be sure, otherwise follow these guidelines.
The standard water level should be halfway up the skimmer so start from there:

Vinyl liner- drop 1 inch
Plaster or other non vinyl liner- drop 6 inches
Solid cover- drop 18 inches
Mesh liner- drop 24 inches
Automatic cover- drop to the bottom of the skimmer

To drain the water, turn your pump to ‘waste’ until the level is where you want it. It’s important not to over drain the water as the winter pool cover won’t stay up by itself. The other important factor at this stage is responsibly disposing of the water to avoid damaging the environment with all those chemicals. Ask your local authorities for advice so you don’t make mistakes or get fined.

Step 6: Clean or replace your filter.

Filters quickly fill up with all kinds of dirt and grime that they help keep your pool clear of, so they need cleaned or swapped out fairly regularly. Doing this right before covering up your pool will give it the best chance of lasting and working successfully throughout winter and will avoid a whole lot of gunk mixing with your pool water when it’s time to get things back up and running again. If you have a cartridge filter you need to remove the cartridge and clean it by soaking it in water and filter cleaner, then rinse, dry and put it back in place. For sand or DE filters, follow the instructions for backwashing, and don’t forget to change the setting back to ‘filter’ when you are done. Drain any water left in the pump or filter- the same goes for pool heaters if you happen to have one (lucky you!).

Step 7: Rid your pipes of any lingering water.

This step is crucial if your pipes are at risk of freezing. Nobody wants cracked pipes, and blowing out your pipe lines to make sure they are moisture free will minimize the risk. Doing this right is tricky so there is no shame in hiring a professional, but hard core DIYers can follow this guide.
Before you start you will need to remove skimmer baskets, return fittings and drain plugs then set your multiport valve to ‘circulate.’ Attach your Shop Vac or air compressor to the drain plug opening on your pump and start blowing air in to clear the system- keep going until you see bubbles coming out from the return lines and the skimmer.
Next you can vacuum the skimmer until it is completely dry then pop your skimmer plug into the hole at the bottom. You can then plug the return lines with winter pool plugs, as long as you have seen bubbles coming through them first.
Once everything is plugged up, go to your pump and switch it to the ‘main drain’ setting then look out for bubbles at the deep end of your pool. Leave it running for about a minute before turning the valve back to the skimmer line then you can shut off your air compressor or Shop Vac. Put a valve in your pump to avoid any leakage and job done!

Step 8: Take away all the extras.

You will want to make sure your pool is fully and effectively covered so take off any extra bits and pieces that don’t need to be there. Accessories such as ladders and rails can be removed, cleaned and stored safely until the sun shines again, as well as skimmer baskets and for salt water pools, the salt water chlorine generator can be drained, disconnected and powered down. If you didn’t need to follow step 7 you will still need to remove the return fittings, which are around the sides of your pipes and look like big screws.

Step 9: Install the winter cover.

The winter cover is there to protect your pool from the harshness of winter, keeping it clear of rain, leaves and other debris that may try to ruin all your hard work. Most covers lie directly on top of the pool water and are weighted to keep them in place, so you shouldn’t have much trouble once it’s installed. You should, however, have a look every now and again when you are doing light basic upkeep just to be sure. Your winter pool cover pump will help avoid any large puddles of rainwater or melted snow collecting and slowly sinking your cover, so it’s a very worthwhile tool to have!

Step 10: Pat yourself on the back.

The hard work is over. All that remains is to congratulate yourself on a job well done and get ready for jack-o-lanterns, santa claus and fireworks. Cosy up and reflect on the great summer you just had and thanks to your efforts, look forward to a hassle free spring when the time comes to look out the swim suits and uncover your pool once again.

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