Fire Season in California and how it affects your ADU

Fire Season in California and how it affects your ADU

In the sun-drenched expanses of California, the arrival of fire season casts a stark contrast against the state's appeal. The period, recognized for igniting some of the most devastating wildfires in recent history, leaves a path of destruction and loss that affects communities and ecosystems alike. Startling statistics from the Department of Forestry and Fire Protection underscore the state’s dubious distinction as the region with the highest number of wildfires in the United States. As of October 2023, there have been 6,001 wildfires within the year, leading to millions in damages. 

For San Diego, nestled within this fire-prone region, the fire season, stretching from the present moment through the end of November, represents a time where vigilance and preparation are necessary for property owners.

Building an ADU in San Diego with the threat of wildfires necessitates an unwavering commitment to safeguarding investments, tenants, and the broader community. 

Whether it is adhering to the required setbacks, installing fire sprinklers, fire rating construction, brush management, securing comprehensive insurance coverage, or fostering a culture of awareness and safety, every measure becomes a critical step in fortifying your ADU against the dangers of the season.

As an experienced construction company in San Diego, we have laid out important considerations in this article, presenting tips on disaster preparedness and helping property owners protect and fireproof their investment.

Are there restrictions on how close I can build my ADU to the property line?

In most jurisdictions in California, a homeowner can build an ADU 4’ from the rear and side property lines or easement, this is known as a “setback”. If your ADU has an attached garage, that portion of your ADU must comply with regular setbacks required by the jurisdiction, not reduced distances applied to ADUs. This is an important consideration when designing your backyard home. In certain areas, the setback requirements can be more or less depending on the city’s individual ordinances, building type, zoning and the size of the structure.  For example, the City of San Diego allows for no setbacks, although we do not recommend this. Partly because it allows for limited access during construction and inability to use any larger equipment, it may trigger costly fire rated construction, lack of privacy and there are limitations to wall openings (windows and doors) 5’ or less from to the property line. In order to ensure that required set backs are adhered to, OneStop ADU always requires the homeowner obtain a property survey prior to creation of the architectural design. 

Does my ADU need fire sprinklers?

Maybe. This determination is based on a few factors. Although, the 2019 California Building Standard Codes requires sprinklers for all new residential units, ADUs are exempt in certain cases. The 2016 California Senate Bill 1069 exempts ADUs from this requirement if the primary dwelling does not have fire sprinklers.  Multifamily buildings and homes in high fire areas are usually equipped with a fire sprinkler system, triggering this requirement for any ADU built on property. Sprinklers may also be required if your ADU is more than 140’ from the curb due to “hose pull” requirements for access by fire fighters. If a system is required, you can expect it to cost $5K-$10K for design and installation. In addition, there will likely be additional costs to upgrade the water line to ensure adequate flow to the system and the city may potentially require a backflow prevention device at an additional cost to the homeowner.

What is “fire rated” construction?

Fire rating is a term that refers to whether or not your ADU meets the California building fire code. The fire rating is largely based on the location/area of your build and construction is “high fire zones” will require more fire-resistant materials to protect your ADU in the case of a fire. These requirements can also be triggered if your backyard home is built close to another structure or to the property line. An example of materials that tend to provide a higher protection from fire are fire-rated stucco and tempered glass. If a higher fire rating is required for your granny flat, this will likely increase the costs of your construction by $10K-$15K.

Brush Management: Create a Defensible Space around the Property

San Diego, with its characteristic susceptibility to wildfire threats, imposes stringent legal and safety requirements concerning vegetation control for properties. The city mandates the establishment and maintenance of defensible space around a property, particularly one that is proximal to canyon and slope areas. Additionally, there’s an insistence upon the removal of dead and decaying vegetation, and ensuring that plants, trees, and other foliage are pruned and arranged in a manner that mitigates fire spread. Cultivating a defensible space involves meticulously clearing vegetation that may serve as fuel for fires, thereby creating a barrier that hinders the fire’s pathway to structures.

Get Insurance Coverage for Natural Disasters

Insurance is essential for your property protection. However, it's important to note that not all policies cover wildfire damage. Coverage varies by carrier and location. If a wildfire is a covered peril, it may include the dwelling, personal property, loss of rent, and structural damage. Still, some policies may have a separate, potentially higher, wildfire deductible. Landlords should review their policies and consider additional coverage to ensure adequate protection against wildfire-related risks.

Thinking of building an ADU on your property and have questions on how to protect your investment from the perils of fire? Contact OneStop ADU, we will design your backyard home with these factors in mind and ensure compliance with your jurisdiction requirements.

At OneStop ADU, we have a team of experienced professionals who provide granny flat construction services throughout San Diego County, including San Diego, Chula Vista, Oceanside, Carlsbad, and nearby areas.

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