If you live in California, you may have heard the news by now - starting January 2020, solar power generation systems will become mandatory for all new residential buildings less than 3 stories high. If your project falls under this new regulation, you may have already started to contemplate the effects on your bottom line. While the costs are a natural thing to worry about, have you stopped to consider how a solar array can impact your building’s design? For instance, can a rooftop solar system exceed the maximum allowable building height?
Height restrictions exist for a variety of reasons. In the California Building Standards Code (CBC), their primary justification is fire safety. Taller buildings built with combustible construction materials give emergency crews less time to respond and evacuate the occupants due to the poor fire resistance of materials and the quick rate of flame spread.
The CBC establishes maximum building heights based on occupancy, type of construction, as well as the type of sprinkler system. Non-residential buildings of fire-resistive and non-combustible construction typically have a higher threshold, with some building types having no height restrictions at all.
On the other hand, residential occupancies, particularly wood-frame dwellings have lower height limits. For example, the allowable height of a wood frame single-family home ranges from 40 to 60 feet, depending on the type of sprinkler system used. To facilitate the installation of photovoltaic systems, the Building Code grants certain exceptions to its maximum height regulations. Rooftop solar panels affixed to a structure with nothing underneath are not considered an additional story, or extra floor area, and may exceed the height limits as long as the conditions below are met:
1. In all occupancies, the highest point of the structure or panel may extend up to 3 feet above the allowable building height, or 3 feet above the roof of the building directly below, whichever is lower.
2. When installed on flat roofs of buildings of any occupancy other than R-3 and R-4, the highest point of the structure or panel may extend up to 10 feet above the allowable building height, or 10 feet above the roof of the building directly below, whichever is lower.
Note that per the CBC, a building’s height is the vertical distance between the average point of grade adjoining the exterior walls and the average height of the highest roof surface.
Local zoning codes also stipulate building height limits in their design guidelines. There is an array of reasons a zoning ordinance may impose height restrictions for certain occupancies and/or neighborhoods of the jurisdiction: preservation of neighborhood character, maintaining views of important buildings, and air navigation safety, just to name a few.
Often, building heights correlate to setback distances, with longer setbacks allowing you to build higher. Homes with pitched roofs typically have higher limits than those with flat roofs.
There are many other variables, and the requirements fluctuate between jurisdictions. For example, in San Francisco, the height limit in most residential areas ranges between 35-40 feet. In Los Angeles, the height of a single-family dwelling is mostly limited to 28 feet if the roof has a pitch of less than 25% and 33 feet for homes with steeper roofs. Solar structures in Los Angeles may project up to 3 feet above the surface of the roof, even if the roof is at or above the height limit. System height exceptions vary between cities and counties, so take the time to do your research before you install your solar system.
Building and zoning codes may establish height limits, but there are some other factors to consider as well when determining the solar system height and location. Environmental factors such as wind and heat, as well as the location of roof vents and HVAC units, must all be taken into account. If the solar array is installed too close to the surface of the roof, the panels may overheat and lose their conversion capacity. On the other hand, too much clearance may lead to increased exposure to wind forces and result in damage to the solar panels and adjacent properties. Roof vents and HVAC units require ample clearance to function properly, and the layout of the solar panels must be designed with this in mind.
Can your roof support the added weight of the solar panels? Before you commit to purchasing the system, get a structural engineer to evaluate your home’s roof structure, and see if additional reinforcement is needed.
Will your roof need repairs or replacements after the solar panels have been installed? The condition of the roof covering is another factor to consider. Most PV systems have a lifespan of 25 to 30 years, and if you doubt that your roof covering will last that long, you should replace it before you install the solar panels.
Whether you’re installing solar panels on a new or an existing building, there are many variables to figure out to make your project a success. Our engineers can help. We will confirm the local and state height restrictions, verify the roof’s ability to support the solar panels, get your project permitted and make sure that installation goes off without a hitch. Let our team of experts put your mind at ease. Contact us at (877) 704-5727 or email us at firstname.lastname@example.org to discuss your project and get a free quote today.
Design Everest is OPEN! We work remotely and are fully committed to taking on and delivering projects.
Design Everest’s remote working model can safely take-up and deliver your projects within the current government guidelines on COVID-19 (a.k.a Coronavirus). This applies to many of our project scopes, including architecture, civil engineering, structural engineering, and construction administration across California.
Design Everest is set up to remotely leverage digital platforms (virtual meetings, calls, emails etc.) in client-facing and internal operations. Over the years, we have advanced this ability to the extent that we can continue supporting new and existing clients across many of our projects. Even projects that need an on-site visit can be fulfilled safely via video calls or in-person visits, where permitted.
Note that the present government guidelines permit the delivery of essential services, including those related to construction.
YES, Design Everest's remote working model enables us to work safely with all clients, suppliers, industry partners, and internal staff as per government guidelines.
Design Everest can still support many of our types of projects (new or ongoing) safely. For example, new custom homes, accessory dwelling units, civil plans etc. We are committed to delivering these remotely and safely as per the current government guidelines. In case of any external dependency that is unavoidable/unavailable, your assigned Custom Success Manager or Project Manager will keep you posted on it and try their best to keep your plans in-progress.
YES, our remote working model enables us to be fully committed to ongoing projects. In case of any external dependency that is unavoidable, unavailable or unsafe, your assigned Custom Success Manager or Project Manager will keep you updated and try their best to keep your plans in-progress. If an on-site visit is not feasible via a video call, we will try our best to fulfill the visit safely, where permitted.
Some of our clients are already going ahead with their projects with us via video calls or virtual meetings. Your assigned Customer Success Manager or Project Manager is happy to help you with this, where needed.
There are multiple reasons for this. It's typical to plan the construction step in the summer. So, clients get started on the pre-construction steps (architecture, engineering, and construction admin) in winter or spring to stick to planned timelines.
Projects such as Accessory Dwelling Units (ADUs) and Additions/Remodels enable clients to rent/resale and generate revenue. Meanwhile, many clients are concerned about protecting their families and businesses against earthquakes by retrofitting their homes and buildings. These are just a few of the various reasons why it’s still reasonable for clients to stick to their construction plans.
Feel free to phone us at (888) 311-3015 Alternatively, you may contact your assigned Custom Success Manager or Project Manager directly via phone, email or virtual meetings.
To summarize, Design Everest is OPEN and able to serve new and existing clients, affiliates, suppliers, and industry partners.
Stay safe and rest assured that Design Everest can help you go ahead with your plans as per the recommended safety guidelines!