Rain Barrel Savings Calculator
Calculate how much rainwater you can collect and save with rain barrels.
Roof area connected to gutters (not total roof area)
Montreal receives approximately 1000 mm of rain per year
Results
Annual Collection
74,320 L
Barrels Needed
6
Annual Savings
$423.62
Each average rain event produces approximately 1,115 L of collection
Methodology & Notes
Calculation based on average Montreal rainfall (~1000 mm/year) and an 80% collection efficiency. Savings are based on City of Montreal water rates (~$5.70/m³). Recommended barrel count is based on an average Montreal rain event of 15 mm.
Get an Accurate Free Estimate
These calculators provide rough estimates. For an exact price, call us or send photos of your project.
“I recommend every Montreal homeowner install at least two rain barrels — one for the front downspout and one for the back. It reduces your water bill, takes pressure off the storm drains, and your garden plants love chlorine-free rainwater.”
How to use this tool
Enter the area of your roof that drains to the location where you want to place rain barrels. The calculator uses Montreal's average annual rainfall to estimate how much water you can collect per year, the number of barrels needed, and your potential savings on municipal water costs. Roof area is measured as the footprint of the section draining to one downspout.
Why it matters
Rain barrels reduce stormwater runoff, lower your water bill, and provide chemical-free water for gardens. Montreal receives an average of 1,000 mm of rainfall annually. Collecting even a portion of this from your roof reduces the load on municipal storm drains and helps prevent basement flooding. Rainwater is naturally soft and free of chlorine, making it ideal for watering flower beds, vegetable gardens, and newly planted trees.
Frequently Asked Questions
How much water can I collect with a rain barrel in Montreal?
With Montreal's average 1,000 mm of annual rainfall, a 200 sq ft roof section can collect about 4,700 litres per year — enough to fill a standard 200-litre barrel 23 times. That saves roughly $30 to $50 annually on your water bill.
Do I need a permit for a rain barrel in Montreal?
No, rain barrels do not require a permit in Montreal. The city actively encourages rainwater collection as part of its stormwater management strategy. Some boroughs even offer subsidies or free rain barrel programs — check with your arrondissement.
When is the best time to install rain barrels in Quebec?
Install rain barrels in April or early May before the rainy season begins. Disconnect and drain them by mid-November before freezing temperatures arrive. In Montreal, the peak collection months are May through September when most rainfall occurs.