The Engineering Reports You’ll Need

During our free consultation calls, we frequently get two questions about engineering:

What engineering reports will I need?

and

How does New Avenue work with engineers?

Here, New Avenue design professional Cindy Lan shares her expertise to help you understand how engineering fits into the New Avenue process.

The reports you'll need to permit your ADU, addition, or custom home

Nearly every project requires engineering. To get a building permit from the city, you'll most likely need some or all of these engineering reports, which must be completed by state-licensed professionals:

• Surveys - required for all projects where there will be construction outside of an existing building envelope. For projects adding an ADU or additional space, necessary close to 100% of the time to ensure the project meets setback requirements.
  

• Soils/geotechnical report - required for most steep slopes and where there is liquefaction, overall about 25% of our projects.
  

• Structural engineering report - required close to 100% of the time.
  

• Energy efficiency report - required for 100% of jobs.

It's a lot to manage, but we're here to help! When you work with New Avenue, your design professional will advise you on the engineering reports you need and will coordinate with the engineers.

The details: Who you'll need and what they'll do

Here's a little more on the engineering reports you'll need and the people who will complete them. Keep in mind that these aren’t self-appointed engineers; they are legally licensed by the state like doctors, architects, and lawyers. 

Surveyor

If you’re adding an ADU or new space to your home, odds are your project will require a surveyor.

The city may not require a survey for simple projects. For example, if you’re building on a slope that’s less than 20% and no part of the proposed project is within the required setback, you may not need one. (However, it is important to know for certain that you’re working within a setback.

But even if your city doesn’t require a survey, your general contractor may ask for one, especially if it’s not a flat site. A survey gives your team critical details about your site and can prevent expensive mistakes (like building too close to the property line).

A note about garage conversions: If your garage sits closer than four feet to the property line (as most Bay Area garages do) and you are converting it to an ADU, you will need to get a survey. Once construction begins, the surveyor will return to the site to mark the locations of the existing footings. Inspectors will check for this during construction. 

Geotechnical Engineer

A geotechnical engineer can analyze the soil at your site and provide any necessary soils reports. This engineer also helps make sure your home is safe by spelling out the requirements for a stable foundation and recommending a suitable foundation system for your property.

Soils reports are generally required for new homes but aren’t always required for ADU projects. That’s because there’s typically an existing structure on the property.

But, as with a land survey, there are times that a soils report is important, especially if the lot isn’t flat or if you’re building more than one story. It gives your design/build team the information they need to create a home that will last for a hundred years or more. A good geotechnical engineer can uncover invisible conditions that may affect your home down the line. With the proper reports, your designer can plan for those conditions.

If you’re building near running water such as a creek or underground culvert, you may need to have a hydrologist visit your site. If your project is in a liquefaction zone, you’ll need a complex report that will cost more than a basic soils report. 

Structural Engineer

Cindy explains the structural engineer’s job with an analogy:

“I like to say that the designer/architect designs the skin of the body, how it looks, size, shape, etc. The engineer resolves the insides of the body, the skeleton—all the concrete, wood and hardware that connects everything.”

A report from a structural engineer is required when your project includes any kind of custom design (and in the Bay Area, nearly every project requires some custom design, including drawings and calculations.)

Your design/build team will work with the structural engineer to make sure your new home is safe and will stand up to the forces that act on a home throughout its lifetime.

Title 24 Energy Engineer

If you’re in California and are building a new home, an addition, or a remodel that affects windows, exterior walls, ventilation, or climate control, you’ll need a Title 24 report to get your permits.

California’s Title 24 spells out the requirements for energy efficiency in residential buildings. Factors include the volume of your home, the envelope of insulation around it, the “holes” in that envelope (such as windows and doors), and the specifications of your heating/cooling system and water heating system. 

An energy engineer will manage the energy calculations for your new home or ADU and provide the Title 24 report you need. More importantly, your Title 24 engineer will help you get a home that is a healthy, safe, and energy efficient place to live.