What is the best month to replace a roof in Ontario?

Canadian weather is incredibly unpredictable and highly variable (we’re sure you’ve already noticed!). But when should you not put a new roof on? Read our experts’ guide to learn the best month for a roof replacement in Southern Ontario. 

Fall (September, October, November)

Fall tends to be our busiest season. With cool, more consistent temperatures and weather consistency, it’s often considered the best time to replace roofs in Ontario. 

Temperatures range from 7 to 29 degrees, allowing for better working conditions for installers and fewer rain delays. Lower humidity and less rain allow shingles adequate time to seal for a longer-lasting roof and guttering replacement before we enter winter. We’re, of course, speaking in averages - if we experience a frigid fall, the temperature can sometimes fall below ideal for less secure sealing and cracked caulking. 

If homeowners have been putting off their roof replacements or waiting for their contractors to get through a backlog of busy summer roofing work, they may scoop up a replacement date in the fall before winter temperatures drop to minimize their winter heating expenses. Unfortunately, if you choose to replace your roof in those highly sought-after fall months, you’ll face scheduling delays unless you plan to beat the rush. 

Pros of Fall Roof Replacement 

• More consistent temperatures

• Less rainfall and snowfall interfering with roof installation

• Asphalt seals securely

• Safer temperature for crews to work efficiently

Cons of Fall Roof Replacement

• Scheduling delays during the busy season

• Premium installation rates and higher new roof cost

• Temperatures may quickly become too frigid

If you choose the fall to replace your roof, plan at least 1-2 months in advance to set a prime date aside and put more cash aside for a potentially higher roof replacement cost. 

Winter (December, January, February)

Cold, windy temperatures, winter ice, and snowstorms make it challenging to get outside some days, let alone climb a ladder to replace a roof. Beyond the issues that extreme weather conditions pose to interrupt projects for a roofing replacement crew, cold weather makes materials crack, creating a poor seal and cracked caulking. 

Despite its challenges, expert roofers may still be able to install your roof during the winter if the conditions permit. And while tar sealant can take longer to seal when it's cold, many roofing companies may use hand-sealing techniques to secure shingles firmly. 

Pros of Winter Roof Replacement 

• Quick turnaround time with best roofing company availability during the slowest season

Cons of Winter Roof Replacement

• Cold weather can crack materials and weaken seals

• Cold weather can make asphalt shingles brittle, making cutting/nailing more difficult

• Extra labour costs if hand-sealing is required

• With fewer daylight hours, jobs may take longer to complete

If you choose the winter to replace your roof, plan at least 1-2 months in advance. While roofing companies may have a more flexible schedule, you should ensure they have the needed materials ready when the weather forecast clears.

Spring (March, April, May)

As winter comes to a close, warming weather brings about the season of spring cleaning and home improvement projects. Aging roofs can take a beating during the winter, causing damage, leaks, and other issues that make a spring roof replacement a top priority. 

The busy season hasn’t yet taken hold, so roofing companies have increased availability - especially if you hop on making those calls proactively in February or March. If you wait too long, spring rain also becomes an issue. 

You may even pay a little less for your cost of materials in the slower spring months. 

Pros of Spring Roof Replacement 

• Better roofing company availability

• Less humidity for stronger sealing

• You don’t need to worry about hot or cool air escaping as the crew works

• Caulking adheres best in warm, not hot weather

Cons of Spring Roof Replacement

• Frequent rain can cause delays

If you choose to replace your roof in the spring, plan 1-2 months ahead and stick to early spring months before the rainy season takes hold. 

Summer (June, July, August)

The conditions can get pretty hot and sunny during the most popular month for a roof replacement. But does that make these months the most ideal for replacing your roof? It’s a relatively good season that comes with some pros and cons. 

Early summer is relatively warm but not too hot. Extreme summer storms haven’t yet arrived, and the sun produces just enough heat for the tar strip on asphalt shingles to activate and adhere. You’ll be faced with crowds of homeowners competing for these popular months, which can cause delays in your installation date. Later summer brings about more extreme temperatures that can make working conditions difficult and overheat shingles to the point of weakening. 

Pros of Summer Roof Replacement 

• Consistently warm weather 

• Fewer, shorter rain showers

Cons of Summer Roof Replacement

• Late summer can get humid, weakening seals

• Hot weather creates difficult or unworkable conditions

• Heated asphalt shingles can soften

If you choose to replace your roof in the summer, book at least 2-3 months in advance to secure a date with your roofing contractor. Choose the earlier summer months before the humidity skyrockets, making difficult working conditions and overheated asphalt shingles. 

When should I replace my roof?

The best month to replace a roof in Ontario is September. 

Though the temperatures hit that sweet spot and roofers are less busy, our roofing company in Hamilton is available year-round for your roofing needs. Get a free cost estimate - call (905) 544-4667 today.