As solar energy becomes more accessible and affordable, Ontario homeowners are asking: Is my roof ready for solar panels?
At T. Simpson Roofing, we know a strong, well-prepared roof is the foundation—literally—for any successful solar installation. This guide walks you through everything to ensure your roof is solar-ready for years, if you’re considering solar panels, planning a roof replacement, or doing your homework.
Installing solar panels isn’t just about pointing them at the sun. It starts with the right roof. Before mounting a panel, your roof must meet a few important criteria:
Solar panels may look sleek and lightweight, but together with mounting hardware and ballast, they can add 3–5 pounds per square foot to your roof. Most modern roofs can handle this, but older homes may need reinforcement. Before installation, a professional inspection is essential to verify your roof’s load-bearing capacity.
Solar panels are a long-term investment. If a roof is nearing the end of its life, installing solar panels on it could mean removing and reinstalling the system in a few years—an expensive and avoidable headache.
Your roof should have at least 10–15 years of remaining life before adding panels. If not, consider a full replacement first. T. Simpson Roofing specializes in expert roof replacements that are built to last and ready for future solar.
Not all roofing materials suit solar. Here’s a breakdown of how common materials compare:
Asphalt shingles are the most popular roofing material in Ontario due to their cost-effectiveness, durability, and compatibility with most solar panel mounting systems.
Clay and concrete tiles are beautiful, but they are challenging for solar panel installation. These materials are brittle and prone to cracking during mounting if not handled carefully.
Installation tip: Installers often remove and replace tiles at panel attachment points with flashing and brackets designed for solar applications.
Flat roofs require a different approach. Installers use ballasted racking systems or tilted mounts that optimize sun exposure while minimizing roof penetrations instead of drilling into the structure.
Built-up roofing systems like tar and gravel are common in older or low-slope residential and commercial buildings. These roofs can support solar, but special attention must be paid to waterproofing and structural assessment.
To get the most from your solar system, position panels where they’ll soak up the most sun.
In Ontario and throughout the Northern Hemisphere, south-facing roofs receive the most consistent sunlight. If that’s not an option, east- and west-facing roofs can still perform well with slightly reduced efficiency.
In Ontario, a roof pitch between 30–40 degrees offers optimal solar exposure. However, installation crews can adjust the panel tilt angle using specialized racks.
Not every home has the ideal roof angle or direction, but that doesn’t mean solar is off the table. Adjustable mounting systems, solar pergolas, or ground-mounted arrays may be alternatives.
The average Ontario home uses about 700–900 kWh per month. Every 1 kW of solar requires about 65–75 square feet of unshaded roof space. Your installer will assess your electricity bills and recommend a system size based on your usage.
Chimneys, skylights, dormers, and plumbing vents can limit usable space and create shading. A good installer will design around these features to maximize performance while preserving aesthetics and roof integrity.
Yes, solar panel systems often involve drilling into your roof—but don’t panic. Professional installers use flashing, sealant, and waterproofing techniques to keep your home safe and dry. Choosing experienced roofers (like our team at T. Simpson) ensures proper installation from day one.
No—when done right. Solar panels can extend the roof’s life by shielding it from sun, wind, and rain. However, poor workmanship can cause leaks, so always hire certified professionals.
Some homeowners are considering solar shingles and integrated solar roofing products, beyond traditional rack-mounted systems. These systems blend the energy-producing power of solar with the form and function of traditional roofing.
These innovative products resemble standard roofing shingles but function as mini solar panels. They’re sleek and aesthetically pleasing, though still more expensive and less efficient than traditional panels.
These full-roof systems, offered by a few premium manufacturers, replace conventional roofing with integrated photovoltaic materials. They’re ideal for new builds or full roof replacements—consider cost, warranty, and local installer availability.
Before solar installation, schedule a professional roof inspection. A certified roofer will assess:
If issues are discovered—missing shingles, soft spots, or inadequate ventilation—handle them before installing panels. This reduces the chance of needing panel removal later for repairs.
Do solar panels void my roof warranty? Not if installed correctly. Work with certified roofers who coordinate with solar installers to preserve warranties.
Will my roof need extra maintenance with panels? Not necessarily. Panels can actually protect the roof. Just monitor debris buildup and check for leaks after heavy weather.
Can I install solar on a new roof? Yes—and it’s often the best time. Replacing your roof before going solar ensures maximum lifespan and saves on future removal and reinstallation costs.
Next Steps: Planning Your Solar Roofing Project
Are you thinking about going solar? Here’s how to get started:
At T. Simpson Roofing, we’ve been helping Ontario homeowners protect their properties for over 30 years. Whether you’re prepping for panels or in need of a full roof replacement, our expert team is here to help.
Contact us today for a free quote or consultation, and take the first step toward a solar-ready home.
