Orange County Construction Cost Per Square Foot

The Orange County construction cost per square foot varies greatly depending on a number of different factors.  First, are you talking about residential construction or a large commercial project?  Are you only looking for a room remodel, or do you need a large luxury apartment building constructed from scratch?  Obviously, the cost will be different depending on the project, but we will review the average cost per square foot range for different categories in Orange County, CA.

Remodel an Existing Structure

When dealing with an existing structure, the cost per square foot range is usually less than an addition or new construction.  However, it’s important to make sure that the existing structure can support the weight of the remodel.  The average Orange County construction cost per square foot to remodel an existing structure runs between $100 – $200 per square foot.  Kitchen and bathroom remodels will usually cost more than bedrooms, and the type of finishes you choose will play a significant role in the cost.  For a luxury or custom remodel with higher-end finishes, your cost can easily run up to $300+ per square foot.


Additions usually cost more money than remodeling an existing structure, because new walls, a foundation, and a roof needs to be installed also.  Brand new, second story additions are also usually more costly than first-floor additions.  Often, for older homes, the original foundation will need to be redone in order to support a second-story addition, which can raise the cost significantly.  Generally, the Orange County construction cost per square foot range for additions is between $150 – $300 per square foot.  The low end of the range would account for small, one-story additions, while the higher end accounts for larger, second-story additions.  For a custom or luxury addition, your cost will be closer to $300 – $500 a square foot.

New Construction

The Orange County construction cost per square foot for new construction tends to be more expensive than remodels and additions, because the whole house has to be built from scratch.  Not only is the construction cost usually higher, you will also have additional architect, engineering, permitting, and possible impact fees.  In addition, low-end housing will obviously cost less than a brand-new custom luxury estate.  It’s important to keep this in mind when evaluating Orange County construction cost per square foot ranges.  Typically, the new construction cost per square foot for Orange County is between $200 – $500 per square foot.  

A Word of Caution

When evaluating the Orange County cost per square foot range, it’s important to know that you really can’t compare apples to apples.  For example, a 1,000 square foot, lower-end, new construction build could easily cost less than a luxury, 1,000 square foot remodel.  Because of this, many homeowners are often confused as to why the cost per square foot for their particular project doesn’t meet the averages you see on Homeadviser.  It’s incredibly important to note that Homeadviser only uses averages throughout the entire state, and not in just Orange County, CA.  Orange County, CA tends to have higher construction costs than the California average.  The higher building costs go along with the higher housing costs.  Additionally, when comparing Orange County construction cost per square foot bids, take into account the quality of the materials, the amount of service you’re getting, and the projected time frame.   Remember that no two contractors are the same, and you might be comparing apples to oranges, instead of apples to apples.

Superior ADUs

Our company, Superior ADUs builds accessory dwelling units for our clients across Orange County, CA and surrounding areas.  We are a team of real estate agents and brokers, architects, designers, contractors, developers, and project managers who work in the Orange County area.  The numbers above are based on our experience working in construction in Orange County over the last several years.

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