How to Prepare Your Roof for Solar Panels

By Jane Marsh

There’s plenty to get excited about regarding solar energy in the United States. According to the U.S. Energy Information Administration (EIA), U.S. single-family households generated 3.7% of their electricity from solar energy.

With the implementation of the Inflation Reduction Act in 2022, a Princeton University report predicts U.S. solar will increase five times per year by 2024, amounting to an additional 49 gigawatts (GW) of utility-scale solar annually. By 2030, Princeton says solar generation could reach 100 GW annually.

Homeowners are eager to adopt residential solar power. For one thing, installing solar panels on your roof saves money on utility bills, provides clean energy, and increases your home’s resale value.

If you’ve decided to jump on the solar train for your own house, there are a few things you should do to prepare your roof for solar panels.

See Also:

5 Steps to Prepare Your Roof for Solar Panels

How to Prepare Your Roof for Solar Panels: Workmen in safety gear lifting a panel onto a residential roof
The installation team secures solar panels to a roof as part of the Spokane Indian Tribe’s DOE co-funded Children of the Sun Solar Initiative. Photo from Tweedie Doe, DOE
U.S. Department of Energy from United States – Children of the Sun Solar Initiative
  1. Schedule an Inspection

The first step to preparing your roof for solar panels is to reach out to a professional roofing inspector. An inspector will come to your home and inspect the roof and attic to look for leaks, cracks, and other damage.

You should also contact a certified energy specialist or builder to determine whether or not your roof can accommodate the weight of solar panels.

  1. Consider Replacing the Roof

Asphalt shingles are the most popular roofing materials, with a life span of 15 to 30 years, depending on your region’s climate.

If adequately maintained, your roof’s gutters can last nearly as long as your shingles. A gutter’s life span decreases with cracks and water leaks or a buildup of leaves – dying leaves emit nitrogen that can corrode the gutter’s surface.

If your inspector finds roof damage or you know it’s nearly reached its life expectancy, you may consider replacing it entirely before installing solar panels.

  1. Determine the Amount of Sunlight

Although solar panels work in all weather conditions, installing them may be more practical if you live in a sunnier region.

Solar panels need ample sunlight for optimal performance. For instance, homeowners living in the southwest, where there are about 300 days of sunshine annually, are prime candidates for solar panels.

However, don’t be discouraged if you live in a rainy state like Washington or somewhere that snows for half the year. You can still prepare your roof for solar panels and benefit from energy savings. Simply cut back trees that shade or dump debris on your roof. A professional can help you remove heavy branches without damaging your home.

  1. Take Measurements

You’ll want to measure the length and width of your roof to determine how many solar panels you’ll need to meet your household’s energy demand. It may be easiest to measure your roof in sections, including all eaves, grooves, and peaks.

According to EnergySage, most homeowners require 17–21 solar panels to cover 100% of their household’s energy needs. A solar installation expert will determine the exact amount by calculating your annual electricity usage, the solar panel wattage, and the approximate production ratio of the panels.

Systems need between 280 and 351 square feet to fit correctly, with most solar panels measuring 17.55 square feet. When you determine the number of panels needed, multiply the panel size by that number to know the required square footage.

  1. Reposition Roof Fittings

Take stock of your roof fittings – chimneys, satellite dishes, antennas, and others – and figure out where to reposition them.

Sketching your roof with your solar panel system in place is a good idea to create a blueprint of each fitting’s new placement.

Check with a licensed contractor to ensure the fittings meet specific building codes. For instance, a licensed plumber may have to relocate any roof vents for you to meet municipal building requirements.

Solar Panels Are Becoming the Norm

Solar panels are rapidly becoming the norm for U.S. households thanks to federal tax credits and other state rebates and incentives. If you’ve chosen to install solar panels on your roof, you’re in good company. Taking the time to prepare your roof for solar panels will ensure satisfactory installation and effectiveness.