After remodeling a home to increase the total square footage, how will annual property taxes be affected?

Asked by Trulia San Jose, San Jose, CA Wed Nov 28, 2012

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Ron Fehr, Agent, Campbell, CA
Wed Nov 28, 2012
Generally the assessed value of the improvement will be added to the prior assessed value. Assessments are not based on market value so if you want to know exactly how the value of the remodel is determined, it would be best to contact the County Assesor's office.
1 vote
charles butt…, Agent, san jose, CA
Wed Nov 28, 2012
Thank you for your question:

As the others pointed out the value of the new improvements will be added to the current assessed value of the property. For all practical purposes, in most cases, the added, assessed value of the improvements will be equal to the cost of the improvements.

However, in conversations that I have had with The Santa Clara County Assessor's Office, the County Assessor's Office is not limited to the actual cost of the improvements and The County Assessor's Office may choose to use another number, such as what The County Assessors's Office determines to be the actual value of those improvements, rather than the actual cost of the improvements.

This is particularly true in those cases where the homeowner did the work him or herself at a much lower cost than would have been charged by a General Contractor.

Fortunately, in my opinion, The Santa Clara County Assessor's Office is staffed by some very knowledgeable and very professional people. In my opinion, and experience, The Santa County Assessor's Office is one of the better County Assessor's Offices in The State of California.

Essentially, the additional assessed value will be equal to the cost of the improvements in most cases, however The Santa Clara County Assessor's Office says that they are not limited to that, and that they may come up with another number in some cases, if they determine that another number is more appropriate.

Fortunately, if you do not agree with that number, you can appeal the decision. If you make a reasonable case, and you have documented your case well, my experience with appeals to The Santa Clara County Assessor's office is that you will usually win an appeal, if your appeal is reasonable and well documented.

Thank you,
Charles Butterfield MBA
Real Estate Broker/REALTOR
American Realty
Cell Phone: (408)509-6218
Fax: (408)269-3597
Email Address:
3 votes
Michael Cheng, Agent, San Jose, CA
Wed Nov 28, 2012
Trulia, are you looking to renovate a home for one of your executives? If so, the annual property tax will be adjusted based on value of the added improvements for the renovation.
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3 votes
Juliana Lee, Agent, Palo Alto, CA
Wed Nov 28, 2012
The Santa Clara County Assessor's website has a Frequently Asked Questions page at:

Click on "New Construction" to see information related to an addition.

The most relevant FAQ is:

Does the assessor pick up the value of every little bit of work that I do on my property?

No. The State Board of Equalization has offered seminars on the topic: What constitutes new construction? It really boils down to the value of the improvement, and its newness. Our office receives copies of permits from the various jurisdictions in the county on a regular basis. Many of these permits are purged up front (miscellaneous electric, special inspection, etc.) and are considered not reappraisable.

The sales price per square foot for a San Jose home is about $350-$400.

If you demolish the current home and build a new home in San Jose the average increase in sales price for the new home will be about $225 per square foot.

If you are adding square feet to your house you will almost surely be doing electrical work. I would strongly recommend you get permits especially if you think you will sell your house in the future.

Juliana Lee, MBA LLB
cell: 650-857-1000
Top 3 agent nationwide at Keller Williams Realty

Over 20 years experience
Over 1000 home sales completed in Santa Clara and San Mateo counties
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2 votes
Terri Vellios, Agent, Campbell, CA
Wed Nov 28, 2012
To tag offer of Michael Cheng, providing that permits were pulled. Otherwise, the tax assessors will not be aware of the improvements.
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1 vote
Sam Shueh, , San Jose, CA
Sun May 3, 2015
To a great deal. Proposition 13 rulings applies. Call your county assessor office for formulas used.
0 votes
Sam Shueh, , San Jose, CA
Sun May 3, 2015
To a great deal. Proposition 13 rulings applies.
0 votes
ctsseo, Home Buyer, San Jose, CA
Mon Feb 2, 2015
Many rental home expenses are tax deductible. Save receipts and any other documentation, and take the deductions on Schedule E. Figure you’ll spend four hours a week, on average, maintaining a rental property, including recordkeeping.
0 votes
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