Is Your Roof Ready for Solar Panels?

Fortunately, many roofs are perfect candidates for solar installations. In this post, we’ll walk you through the key factors that determine your roof’s solar potential, local regulations you should be aware of, and how much you can expect to save by going solar. Let’s dive in!

What Makes a Roof Suitable for Solar Panels?

When determining if your roof is ideal for solar panels, there are several key factors to consider:

1. Roof Orientation and Tilt Angle

The direction your roof faces and its angle play a huge role in how much sunlight your solar panels will receive. In New Zealand, the optimal orientation for solar panels is north-facing to capture the most sunlight throughout the day. However, east- or west-facing roofs can still generate a substantial amount of power—just slightly less efficient.

Roof angle:
The ideal tilt angle for solar panels is typically between 20 and 40 degrees. Fortunately, if your roof’s slope is less than optimal, mounting systems can be used to adjust the panels to the perfect angle for maximum solar gain.

2. Roof Size and Dimensions

The size of your roof directly impacts how many solar panels you can install. For example, if you’re considering a 10kW system, you’ll need enough roof space to accommodate around 25–30 panels. A typical residential solar panel measures around 1.7m x 1m, so make sure you have enough clear roof area to fit the required number of panels.

3. Roof Condition and Material

Your roof’s condition is important for a long-lasting solar installation. If your roof is nearing the end of its life (typically over 20 years old), it may be worth replacing it before installing solar panels. Common roofing materials like metal, asphalt, and tiles are generally compatible with solar, but some roofs with delicate materials like slate may require special mounting solutions.

4. Shade from Trees or Nearby Buildings

Shade can significantly reduce the efficiency of your solar panels. It’s essential to assess whether nearby trees, chimneys, or tall buildings cast shadows on your roof during peak sunlight hours. Even partial shading on a few panels can affect the output of the entire system. For this reason, shading analysis is often included in your solar consultation to ensure you get the best possible results.

Do I Need a Roof Inspection Before Installing Solar?

Yes, a roof inspection is highly recommended before installing solar panels. During this inspection, your installer will evaluate:

• The condition of your roof (is it structurally sound and able to support the weight of the panels?).
• Shading factors (are there trees, buildings, or other obstacles that could block sunlight?).
• Roof angle and orientation (is it facing the right direction to capture optimal sunlight?).

This inspection ensures that your roof is ready for solar installation and can help prevent future issues like leaks or roof damage. It also gives you a better idea of the expected output of your solar system.

New Zealand Solar Regulations: What You Need to Know

In New Zealand, installing solar panels is generally straightforward. Most councils do not require consent applications for solar panel installations, as these are considered energy work. This means you can install solar panels without needing to go through a lengthy approval process.

However, there are exceptions:

• If your property is in a historic or heritage area, you may need to apply for consent.
• If your installation impacts the appearance of your home significantly or exceeds certain height or size restrictions, you may also need consent.

It’s always a good idea to check with your local council or installer to ensure that your installation complies with all relevant regulations.

How Much Can I Expect to Save with Solar Panels?

One of the biggest advantages of installing solar panels is the potential to save money on your electricity bills. Let’s break it down:

• Energy savings: A well-designed solar system can reduce your power bill significantly. The exact savings depend on the size of your system, your energy consumption, and your location. Homeowners can typically expect to see savings of 50–80% on their electricity bills.
• Selling excess power: If your system produces more power than your household consumes, you can sell the excess energy back to the grid. This can further reduce your power costs or provide credits for future use.
• Return on Investment (ROI): Most New Zealand homeowners see a return on their solar investment in 7 to 10 years. Given that solar panels have a lifespan of 25+ years, that’s a lot of free energy after your initial investment is paid off!

Conclusion: Is Your Roof Ready for Solar?

Determining whether your roof is suitable for solar involves considering several factors, including its orientation, tilt angle, size, condition, and shading. A professional inspection is crucial to ensure everything is in order, and local regulations rarely pose barriers for installations in New Zealand.

Not only can solar panels reduce your electricity bill, but with the right system, you can generate enough energy to sell excess back to the grid, increasing your savings even further.

Curious about how much you could save? Use our Solar Calculator to get an instant estimate of your savings potential and find out if your roof is ready to power your home with renewable energy!