Pool Closing Is More Than Throwing a Tarp Over the Water
Every fall, Toronto and South Mississauga homeowners face the same question: handle the pool closing themselves, or book a professional to do it. The answer depends less on budget and more on what closing actually involves. Done properly, it protects the plumbing, the liner or surface, and the equipment through an Ontario winter. Done poorly, it turns spring opening into a repair bill.
This guide breaks down what a pool closing service actually covers, what drives the cost, and how to decide whether your pool is a good candidate for a DIY closing this year. For the full step-by-step process, our pool opening and closing checklist walks through each task in order.
What a Professional Pool Closing Actually Includes
A closing service is not one task, it is a sequence of them, and skipping or rushing any one of them is usually where the spring problems come from.
Water Balancing and a Final Treatment
Before anything else, the water gets tested and adjusted to target range, then shocked with a full dose of chlorine and treated with a winterizing algaecide. Water that goes under a cover already out of balance tends to come out green in spring, no matter how good the cover was.
A Full Clean
Brushing the walls and floor, vacuuming settled debris, and clearing every skimmer basket and the pump strainer happen before the water level drops. Anything left behind in September is still there in April, just harder to remove from colder water.
Lowering the Water Level
The water gets lowered below the skimmer and return line openings, typically 15 to 30 centimetres below the tile line. How far depends on the type of cover going on. A solid safety cover sits differently than a mesh cover, and the water level needs to match it.
Blowing Out the Plumbing
This is the step that actually prevents freeze damage. A compressor forces all standing water out of the skimmer lines, return lines, and any dedicated lines for water features, and every line gets plugged immediately after. Water left in a line expands when it freezes, and a cracked underground line is one of the more expensive repairs a pool owner can face. It is also the step most DIY closings get wrong, because most homeowners do not own a pool-rated compressor.
Winterizing the Equipment
The pump, filter, heater, and chlorinator get drained, and any salt cell or automation components get disconnected and stored per the manufacturer’s instructions. Left connected and full of water, this equipment is exposed to the same freeze risk as the plumbing.
Fitting and Securing the Cover
The last step is installing a cover that fits the pool with no gaps, then securing it properly with anchors, water bags, or cables depending on the cover type. A cover that shifts or lifts during a winter storm lets debris and sunlight in, which undermines everything done before it.
What Drives the Cost of a Pool Closing
Rather than a flat number, what a closing actually costs comes down to a handful of variables specific to your pool:
| Factor | Why It Matters |
|---|---|
| Pool size and shape | More surface area and more plumbing runs mean more time on every step |
| Type of cover | An automatic or solid safety cover takes longer to fit and secure than a standard mesh cover |
| Equipment complexity | Salt systems, heaters, and automation add extra winterizing steps |
| Water condition going in | A pool that is already out of balance needs more chemical treatment before it can close properly |
| Access to the pool | Tight side-yard access or obstacles around the equipment pad add time |
Get a closing quote in the fall when demand is highest and you are comparing against these same variables on your own pool, not a generic estimate.
DIY Pool Closing vs. Hiring a Professional
Plenty of experienced pool owners in Toronto and South Mississauga handle their own closing every year, and there is nothing wrong with that once you know the process. The steps that tend to separate a DIY closing from a professional one are the ones that need equipment most homeowners do not keep on hand, mainly the compressor for blowing out the lines, and the experience to judge things like how far to lower the water for your specific cover type.
If you are closing your pool for the first time, if your system has a heater, salt cell, or automation you are not fully familiar with, or if last year’s opening turned up any surprises, having a professional handle the closing is a reasonable way to protect the investment while you learn the system.
Mistakes That Turn Into Spring Repairs
- Closing too early. Warm water under a cover for weeks gives algae time to establish before the pool is even shut down for the season
- Skipping the blow-out, or doing it with a shop vac instead of a real compressor. Residual water left in a line is the single biggest cause of freeze damage
- Using a cover that does not fit properly. Gaps let in debris and sunlight, both of which work against everything else done during closing
- Forgetting to drain the heater or filter. These sit outside the main plumbing run and are easy to overlook
When to Close Your Pool in Toronto and Mississauga
The right window is when water temperatures fall consistently below 15 degrees Celsius, which typically lands between mid-September and mid-October across Toronto and South Mississauga, including Port Credit, Lakeview, and Clarkson. Closing before that risks algae growth under the cover through the fall. Waiting too long risks a freeze before the plumbing is fully blown out. Watch the overnight lows more than the calendar date.
Frequently Asked Questions
How long does a pool closing take?
A straightforward closing on a standard inground pool typically takes a few hours from start to finish. Pools with more complex equipment, larger surface area, or difficult access can take longer.
Can I close my pool without draining any water?
Yes. A standard closing only lowers the water level below the skimmer and return openings, it does not drain the pool. Fully draining an inground pool is a separate, more involved process that is not part of routine closing.
What happens if I skip closing my pool for a year?
An uncovered or improperly winterized pool left through an Ontario winter is exposed to freeze damage in the plumbing and equipment, plus heavy algae growth and debris accumulation in the water. The spring cleanup and any repairs typically cost far more than a proper closing would have.
Does the type of cover affect how the pool is closed?
Yes. The water level, the anchoring method, and how the pool is prepared underneath all depend on whether you are using a mesh cover, a solid safety cover, or an automatic cover. Our guide to types of pool safety covers compares how each one fits into the closing process.
Is it too late to close my pool if the weather has already turned cold?
It is rarely too late, but the priority shifts to getting the plumbing blown out and plugged before a hard freeze. If temperatures are already dropping below freezing overnight, treat the blow-out as the most urgent step.
Keep Your Whole Backyard in Mind, Not Just the Pool
A pool closing protects what is already there. If you are also thinking about what the pool and the surrounding space could look like next season, whether that is a resurfaced deck, a new liner, or a full restoration, Destination Pools handles pool restoration across Toronto and South Mississauga. Contact us to talk through what your backyard needs before next season starts.
