California’s New Solar Standards: What Contractors Need to Know

California's New Solar Standards: What Contractors Need to Know

Heads up if you’re a builder in the state of California. New regulations set to go into effect in 2020 will require that most new homes and multifamily structures are outfitted with the ability to generate their own solar power, along with other changes designed to reduce the energy they need to function. Increased costs to builders are estimated to range from $8,000 to $30,000, depending on the size of the array needed, available space for the panels and other hyperlocal factors.

Green, the New Controversy

Because California is already experiencing a housing shortage and a runaway market for the houses that are available, many are questioning the wisdom of this particular move, concerned that it will ultimately hurt both builders and lower income residents who can’t afford to join the solar revolution. Even so, large builders in California have been offering solar panels as an option for years without any visible impact to their bottom line or demand for homes.

Other social issues have been raised, including the fear that low-income Californians will be the only ones left to pay for the power grid, driving their electricity prices through the roof. These are people’s grandparents and parents, in many cases, causing green homes to becoming a polarizing issue. Despite this, the changes to the code seem to be moving forward.

What the Code Says Now

The new building codes aren’t finalized, but the unanimous vote that approved the solar panel language indicates that it’s basically a done deal. As you might expect, the language is dense and contains more exceptions than is strictly necessary, but pay attention if you build:

● New single-family homes
● Low-rise multifamily buildings with three or fewer stories
● High-rise multifamily buildings with 10 or fewer stories
● Hotels under 10 stories
● Other Non-residential buildings, except healthcare facilities, with three or fewer stories.

Below is just an example of changes you should be aware of. If you’re a multifamily or commercial builder, you can pull up the code changes here.

For single family residential builders, your main challenge is going to be finding enough roof space to create a solar zone of adequate size. Here’s what that looks like:

Homes with roof square footage under 10,000:

● No panel sections under five feet in length.
● Minimum size of solar panel bank is 80 square feet
● Minimum total solar zone equal to 250 square feet.

Homes with roof square footage over 10,000:

● No panel sections under five feet in length.
● Minimum size of solar panel bank is 80 square feet
● Minimum total solar zone equal to 250 square feet.


● Homes with designated solar zones that are no less than 50 percent of the potential solar zone area. The potential solar zone area is equal to the total of all low-sloped roofs where the annual solar access is 70 percent or greater and all steep-sloped roofs oriented between 90 and 300 degrees of true north where the annual solar access is 70 percent or greater.

● Homes with a solar zone totaling 150 square feet or more and fitted with demand responsive controls.

● Homes with permanently installed solar water-heating systems with a minimum solar savings fraction of 0.50.

● Homes with three or more stories, a total floor area under 2,000 square feet and a solar zone area over 150 feet.

● Homes located in the Wildland-Urban Interface Fire Area with a whole house fan and a solar zone total area over 150 feet.

● Homes with demand responsive thermostats that also installs at least one from this list:

○ Energy Star compliant dishwasher, Energy Star compliant refrigerator, whole house fan or an electric vehicle charger with a minimum of 40 amps.

○ Demand responsive home automation system capable of controlling appliances and lighting.

○ Alternative plumbing pipes to discharge gray water into the home’s irrigation system.

○ Rainwater catchment system that uses rainwater from at least 65 percent of the roof area.

Like with any changes to building codes, there are likely to be a lot of growing pains as implementation begins of the new solar and energy efficiency standards. California has lofty goals for clean energy – with any luck, these changes to the code will really create a better environment for everyone.

What do you think? There’s plenty of evidence that California has made huge strides in improving air quality with building changes like this, but at some point, the value that comes out won’t be worth what’s put in. Where, exactly, is the tipping point?