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Updated almost 5 years ago, 12/19/2019

User Stats

214
Posts
49
Votes
Gary F.
  • Honolulu, HI
49
Votes |
214
Posts

San Jose ADUs. Experiences to share?

Gary F.
  • Honolulu, HI
Posted

Hello Bay Area BP folks and others. I've been wanting to invest in real estate for awhile. To get started with a low budget I've always thought an in law unit aka ADU, would be a great way to start. My backyard though didn't meet the setback requirements per city codes. However now the State and subsequently the city, have relaxed the codes to encourage homeowners to build. Lucky thing

For those that have an ADU, please share your experiences. Are rental prices on these necessarily lower than the market?

I'm looking into building types. My side area is only 6 ft wide.  Not quite enough for a BobCat to be used. That'll add to the costs since foundation work will have to be done manually. 

Panel prefabricated homes look to be the best choice maybe. As long as they can carry them through that side yard area. 

Any other advice to share is appreciated. Mahalos 

User Stats

27
Posts
20
Votes
Salvador Jimenez
  • Architect
  • Los Angeles, Ca
20
Votes |
27
Posts
Salvador Jimenez
  • Architect
  • Los Angeles, Ca
Replied

This is such a great thread...keep it going people. I just wanted to wish everyone the best of luck in your pursuits to building an ADU in each of your properties. I work for an architecture firm and have been moonlighting for about 6 years now. Typically I work on single family homes but recently I have designed (4) ADU's in southern california and looking to expand to the NorCal region so if there is anyone looking for assistance feel free to reach out to me via PM.

Happy holidays everyone!

User Stats

90
Posts
57
Votes
Adam Mayberry
  • Architect
  • San Jose, CA
57
Votes |
90
Posts
Adam Mayberry
  • Architect
  • San Jose, CA
Replied

Hello @Jim G.

Interesting question. You can now do 700 SF ADU ( since your lot is over min lot size they changed the code) which I influenced, this is By Right and could take about 3 months at the quickest to get a building permit.

R-M Requires a Site Development Permit (to get your duplex) This is an additional process for Entitlement before you can apply for the building permit.  This is usually 120 day process and has additional fees associated with it from planning stand point . HOWEVER you can get a lot more, you could possibly get a triplex, or larger units.  (If someone like myself is involved from Design/Partnership Role, we could possibly squeeze out some value from this.)

San Jose has a General Plan, most likely your R-M is now in Neighborhood Residential Designation, so you must prove your density is compatible with existing neighborhood pattern (50% of properties on your block meet or exceed your proposed density)

Let me know if you want to talk off line!

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User Stats

160
Posts
155
Votes
Chen Zhou
  • Rental Property Investor
  • Santa Clara, CA
155
Votes |
160
Posts
Chen Zhou
  • Rental Property Investor
  • Santa Clara, CA
Replied

Hello everyone, I recently got permit approval in SJ (Willow Glen) for a 630 sqft attached ADU + 170 sqft addition to the existing unit. I'm happy to share my experience working with architect, the city, and contractors here. It took me about 4 months to get my permit and now I'm 3 months away from completion of the construction. Let me know if you have any specific questions.

I do want to point out that starting from July 2018, owners now can rent out both units without living in the property. With more relaxed rules from July 2018, it makes a lot more economic sense to invest into building an ADU: http://www.sanjoseca.gov/DocumentCenter/View/78534

User Stats

308
Posts
227
Votes
Brian Larson
  • Investor
  • San Jose, CA
227
Votes |
308
Posts
Brian Larson
  • Investor
  • San Jose, CA
Replied

@Chen Zhou - thanks for sharing. I am still in the design process for my detached ADU.

Can you please share some potential pitfalls or lessons learned to watch out for with the permitting or building process?

User Stats

34
Posts
20
Votes
Caitlin Bigelow
  • Specialist
  • San Jose, CA
20
Votes |
34
Posts
Caitlin Bigelow
  • Specialist
  • San Jose, CA
Replied

Hi All - I just moved to San Jose (Willow Glen) to expand my ADU consultation business. We've conducted ~130 ADU consultations in the last two months in San Diego, but am still learning the nuances of the Bay Area (permitting process, price per sq ft, etc)

I'm also interested in finding ADUs in progress or completed to do some videos and show people what's possible. So if anyone here has a finished ADU that's well designed I'd love to interview you on camera and do a quick home tour! Please feel free to message me. 

User Stats

160
Posts
155
Votes
Chen Zhou
  • Rental Property Investor
  • Santa Clara, CA
155
Votes |
160
Posts
Chen Zhou
  • Rental Property Investor
  • Santa Clara, CA
Replied

@Brian Larson

I'm still in the middle of construction, so I'm not necessarily aware of all the pitfalls yet. I would say that 

1) it's important to start talking to contractors experienced in building ADUs in the design phase as you would know what everything is going to cost in your design and can iterate your design based on costs. For a lot of people, ADU is going to be used as rental, so it might not make sense to have skylights/bay windows/etc. unless these features are really going to help you increase rental income.

2) don't underestimate the costs associated with getting the permit. Here's my breakdown of the overall project costs - you can see a big chunk of it goes into just getting the permit...

Architect + structural engineer $ 7,000
Park fee $ 4,450
School fee $ 2,192
Permit application $ 2,653
Permit Issuance $ 9,416
Contractor (estimated) $ 170,000
Inspections (estimated) $ 4,000
Landscaping and other miscellaneous $ 300
Total (estimated) $ 200,011 

Happy to share more tips as the project goes. Good luck with your project!

User Stats

25
Posts
5
Votes
Laura C.
  • San Jose, CA
5
Votes |
25
Posts
Laura C.
  • San Jose, CA
Replied

Have recently resumed my research on building an ADU and am a bit horrified at how much prices have gone up. Someone I know had built one (prefab) in the Bay Area about 2-3 years back in the ballpark of $250/SF. I had hoped to use the same firm - I know the prices have been creeping up, but now that same firm is charging an average of $350/SF. That's a 40% increase in a 2-3 year span, holy smokes. I'm going to start looking into things like studio sheds and see how that goes.

User Stats

8
Posts
9
Votes
Jeffery Chang
  • San Jose, Ca
9
Votes |
8
Posts
Jeffery Chang
  • San Jose, Ca
Replied

@Chen Zhou 

If the ADU is less than 500 Sqft, in SJ unified school district, the school fees can be waived. My ADU was smaller than 500, so the fees were waived. 2000+ is not much in the grand scheme, but just thought I throw it out there for everyone.

User Stats

308
Posts
227
Votes
Brian Larson
  • Investor
  • San Jose, CA
227
Votes |
308
Posts
Brian Larson
  • Investor
  • San Jose, CA
Replied

@Jeffery Chang - good point. I saw that too but I am opting to build larger in SJ

User Stats

1
Posts
0
Votes
Replied

Also, looking into ADU's. For the past year. Want to build detached ADU, in Santa Clara. I

Think, Laura C, is referring to the Fairfield  Co.  Sorry to hear they are raising their prices.

Appreciate Chen Zhou, $ breakdown. Very informative having "real"  pricing to work with.

Anyone, have issues/information, on cost of adding separate utility hook up?   Gas/electricity/sewer line? 

User Stats

160
Posts
155
Votes
Chen Zhou
  • Rental Property Investor
  • Santa Clara, CA
155
Votes |
160
Posts
Chen Zhou
  • Rental Property Investor
  • Santa Clara, CA
Replied

@Lee Ozawa

I'm building an attached ADU partly to save cost on utility hook up - it's much easier to extend gas/electricity/water/sewer line within the same house structure (of course there's also the benefit of having the ADU square footage counted as part of the main house in appraisal as it's easier to find comps).

I've heard that it'd be a little more expensive if you have to dig into the ground to extend gas & water & sewer lines into a detached ADU (electricity is easier), so you want to minimize the distance b/w the main house and the ADU hook-ups in your design phase. A good designer should know how to save you $$.

For electricity hook-up, you just need a subpanel and sometimes the city would ask you to upgrade the entire electricity wiring and the main panel. Typically people don't have separate meters for gas or electricity as they are not worth the cost (would cost >$10,000 for PG&E to install separate meters).

Good luck!!

Chen

User Stats

25
Posts
5
Votes
Laura C.
  • San Jose, CA
5
Votes |
25
Posts
Laura C.
  • San Jose, CA
Replied

@Lee Ozawa yup, i'm referring to the fairfield company.  

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User Stats

11
Posts
4
Votes
Binod G.
  • San Jose, CA
4
Votes |
11
Posts
Binod G.
  • San Jose, CA
Replied

pge charges $75 for new gas meter. electric meter is free

User Stats

160
Posts
155
Votes
Chen Zhou
  • Rental Property Investor
  • Santa Clara, CA
155
Votes |
160
Posts
Chen Zhou
  • Rental Property Investor
  • Santa Clara, CA
Replied

@Binod G.

Are you talking about replacing existing meters or adding new submeters?

Thanks,

Chen

User Stats

132
Posts
68
Votes
Paul Merriwether
  • Investor
  • Oakland, CA
68
Votes |
132
Posts
Paul Merriwether
  • Investor
  • Oakland, CA
Replied

@GARY F. FROM San Jose ADU guidelines >>Can I build an ADU on a property where the single-family house is a rental property? Yes. May I rent the house and ADU to different parties? Yes<< Google San Jose ADU

User Stats

160
Posts
155
Votes
Chen Zhou
  • Rental Property Investor
  • Santa Clara, CA
155
Votes |
160
Posts
Chen Zhou
  • Rental Property Investor
  • Santa Clara, CA
Replied

For those who're interested, I completed my ADU project and you can see the 3D visualization of my place here:
https://my.matterport.com/models/hRAxQheq93H?section=media&mediasection=showcase

User Stats

62
Posts
52
Votes
Hai G.
  • Investor
  • San Mateo, CA
52
Votes |
62
Posts
Hai G.
  • Investor
  • San Mateo, CA
Replied

@Chen Zhou that looks great, thanks for sharing. Do you mind going into how long it took for the permitting process and construction time? I’m looking to add ADUs to couple of my properties as well. Thanks!

User Stats

160
Posts
155
Votes
Chen Zhou
  • Rental Property Investor
  • Santa Clara, CA
155
Votes |
160
Posts
Chen Zhou
  • Rental Property Investor
  • Santa Clara, CA
Replied

@Hai G.Every city in the bay area is different in terms of speed. Mine was in San Jose and took about 3 months to get permits. Construction is another 6 months, depending on what time of the year you get started (avoid rainy seasons at all cost!)

San Jose is probably one of the most friendly ones...The city just started an express review service on Tuesdays, where homeowners can make appointments to meet directly with city staff for a single, comprehensive review of their ADU application, for qualifying 1-story units up to 900 square feet. If no revisions are needed, homeowners could potentially walk out with a building permit in less than 90 minutes.

User Stats

5
Posts
1
Votes
Sharon Ku
  • Investor
  • San Mateo, CA
1
Votes |
5
Posts
Sharon Ku
  • Investor
  • San Mateo, CA
Replied

@Ash Hussain which company you get the quote from? I have a second garage in my backyard already that I want to convert it into a 1 bedroom

User Stats

160
Posts
155
Votes
Chen Zhou
  • Rental Property Investor
  • Santa Clara, CA
155
Votes |
160
Posts
Chen Zhou
  • Rental Property Investor
  • Santa Clara, CA
Replied

San Jose 2019 ADU ORDINANCE CHANGES

The City Council voted on Dec. 17, 2019 to update San Jose's zoning code pertaining to ADUs to align with new California State laws that go into effect on Jan. 1, 2020. San Jose's zoning code changes for ADUs are effective immediately. The table below shows the prior regulations and the newly approved regulations.

ITEMPRIOR REGULATION (BEFORE DEC. 17, 2019)NEW REGULATIONS THAT ALIGN WITH CALIFORNIA STATE LAWS
Effective DateCity Council approved the regulations below on July 27, 2018 with subsequent updates approved on May 23, 2019; June 25, 2019; and November 19, 2019.On December 17, 2019, City Council approved the following changes, effective immediately upon their vote on Dec. 17, 2019.
Zoning District

ADUs are allowed:

• In R-1, R-2, and R-M zoning districts on lots that have one single-family residence.

• In Planned Development (PD) districts that are subject to R-1 standards and uses OR where ADUs are not expressly prohibited.

• In a low-density cluster development if it conforms to development standards of the R-1 zoning district, and the development and use standards of the low-density cluster permit.

ADUs are allowed:

• In R-1, R-2, and R-M zoning districts on lots that have one single-family residence.

� On lots with a single-family residence In Planned Development (PD) districts that are subject to R-1 standards and uses OR the ADU conforms to the development and use standards of the PD district.

• On any lot with an existing single-family dwelling unit, where regardless of zoning, the lot has any of the following General Plan Land Use/Transportation designations:

- Residential Neighborhood

- Mixed-Use Neighborhood

- Urban Village or Urban Residential

- Transit Residential or Rural Residential

- Downtown

- Mixed-Use Commercial

• On two-family (duplex) lots and on multifamily properties

• In a low-density cluster development if it conforms to development standards of the R-1 zoning district, and the development and use standards of the low-density cluster permit.

Minimum Lot Size3,000 square feetNo minimum lot size
Minimum Setbacks from Rear and Side Property Lines0 feet for 1-story conversions and new construction.

5 feet for second-story ADUs constructed above a garage or accessory structure.
0 feet for 1-story conversions and new construction.

4 feet for second-story ADUs constructed above a garage or accessory structure

4 feet minimum rear and side setbacks required for detached ADU in multifamily developments.
Maximum Height

For detached ADUs:

Single story – 18 feet maximum
Second story – 24 feet maximum

Attached ADUs are subject to the height limits of the main home.

Single-family properties - No change in height requirements.

Multifamily properties - 16 feet maximum height for detached ADUs.

Rear Yard CoverageArea covered by the ADU, accessory buildings, and accessory structures, except pools, shall not exceed forty percent (40%) of the rear yard.Area covered shall not exceed forty percent (40%) of the rear yard or up to 800 square feet, whichever is greater.
Detached ADU Allowed Locations

Rear yard only, at least 6 feet away from primary dwelling.

May be attached to a detached garage or other existing accessory structure.

Must meet minimum setbacks for an accessory building in accordance with Section 20.30.500.

No changes except that ADUs that exceed forty percent (40%) of the rear yard must maintain minimum 4 foot side and rear setbacks. One-foot overhang for eaves would be allowed.
ADU Size (in sf)
LOT SIZE (SF)ADU MAXIMUM SIZE (SF)
3,000 - 5,444600
5,445 - 9,000700
9,001 - 10,000800
10,001 - Up900
LOT SIZE (SF)ADU MAXIMUM SIZE (SF)
Up to 90001,000
9,000 and greater
1,200
Number of Bedrooms and BathroomsTwo bedrooms allowed on lots with an area greater than 9,000 square feet, and only one bathroom.Up to two bedrooms and two bathrooms allowed for all units.
Attached ADU Maximum Floor AreaMay not exceed 50% of the existing or proposed primary dwelling living area.May not exceed 50% of the existing or proposed primary dwelling living area or 800 square feet, whichever is greater.
Design StandardsVisual compatibility with existing primary dwelling is required.No design standards, except new simplified standards for attached ADU units for historic buildings listed in the Historic Resources Inventory.
Parking requirementsAn ADU requires 1 space unless the property qualifies for an exemption under State law—see the parking requirements.

If a garage has been converted, the main dwelling parking space must be replaced, as uncovered or in front or side setback areas. Parking spaces may be configured on-site per state law.
No change in parking requirements for the ADU.

Replacement parking for garages and carports converted to ADUs will not be required.
Junior ADU
(JADU)
Not allowed.Allow JADU up to 500 square feet within the existing walls of a single-family home. Must include at least an efficiency kitchen. May share a bathroom with the primary unit. Owner-occupancy and deed restriction will be required, subject to State law regulations.