Portola Valley makes it easier to add second living units

New rules allow small accessory housing units in almost all town zones

Fulfilling its goal of encouraging more housing in Portola Valley, the Town Council on Wednesday night, March 13, unanimously gave preliminary approval to a new ordinance offering more flexibility to add additional living units on properties.

The new ordinance allows additional living units in all the town's zones, including nonresidential, as long as specific criteria for access in an emergency are met.

In most cases, the size of the units will max out at 1,200 square feet. On lots that are 3.5 acres or larger, the property owner can have one 1,500-square-foot unit, or two units that meet town regulations. Units inside an existing structure can reach up to 1,700 square feet if they meet certain criteria.

Previously, second units were allowed only on residential parcels of an acre or larger unless they were inside an existing structure. The new regulations tie the maximum size of the units to the adjusted maximum floor area (AMFA) allowed for the site, which means the new rules don't increase the amount of square footage currently allowed on a property.

The adjusted maximum floor area is calculated for each parcel based on its size, average slope, existence of soils prone to landslides and location in a flood plain, and includes all structures on a property.

For those who have less than 1,200 square feet of unused adjusted maximum floor area, a new second unit can't exceed the unused AMFA.

The ordinance permits individual addresses for second units, which will allow for separate utility connections and mail delivery; they can also have a separate driveway if it meets strict criteria for town approval.

The town continues to require the owner of a property with a second unit to live on site if they wish to rent one of the units. No units may be rented for fewer than 30 days.

The ordinance says its purpose is to:

•Create new housing units while respecting the existing character of the town.

•Provide housing that responds to residents' changing needs, household sizes, and increasing housing costs; and provide accessible housing for seniors and people with disabilities.

•Offer environmentally friendly housing choices with less average space per person and smaller associated carbon footprints.

•Promote affordable housing for people who work in town.

As in earlier meetings on the issue, the council heard from several residents. Nan Shostak said she worried about increasing the density in the town. "Portola Valley is environmentally fragile," she said, and at risk in an earthquake. She also asserted that units of up to 1,700 square feet, which the town had been considering, would not be affordable.

Robert Shostak said the opportunity to build more housing units could also be seen as "a magnet for developers."

But resident Bruce Roberts argued that larger units should be allowed inside existing structures, citing his own existing 1,632-square-foot unit in the lower story of his home. "There's a huge difference between internal and external" living units, he said.

Longtime resident George Andreini said he was afraid the new ordinance is "a sweeping change to what the town of Portola Valley used to be." He said he is afraid money will motivate building second units and "it compromises what Portola Valley stands for."

Those fears may have been alleviated by the council's unanimous consensus to cap the size of most of the town's second units at 1,200 square feet. Council member John Richards, who is an architect, showed floor plans of two- and three-bedroom homes that were 1,200 square feet or less. "1,200 square feet is not a small space," he said.

Council member Craig Hughes said, "I think retaining the flexibility is probably important," and advocated choosing a cap size on the low end while not ruling out a future increase.

Council member Maryann Derwin said she has a 750-square-foot second unit and "it seems really spacious to me."

"I think people are happier in smaller spaces," she said. "You have less stuff."


Sign up for Almanac Express to get news updates. Follow us on Facebook and Twitter.

Or show your support for local journalism by subscribing.

What is community worth to you?
Support local journalism.


32 people like this
Posted by Concerned
a resident of Portola Valley: Central Portola Valley
on Mar 16, 2019 at 4:20 pm

More housing is simply not appropriate for Portola Valley. As a town founded on rural values with expansive country living, this will certainly increase our density in town. I don’t see issues like traffic being addressed, there will certainly be an impact on our roads. While I think it’s appropriate on those lots with 2+ acres it is especially tacky on smaller lots to push this through. I think the town needs to listen to residents on this. There could be lawsuits. Not a very smart move considering Bay Area is getting more dense, we shouldn’t respond to the pressure by caving and building excessive housing. Just ridiculous

6 people like this
Posted by Menlo Boomer
a resident of Menlo Park: Linfield Oaks
on Mar 17, 2019 at 6:50 pm

Ugh!! Thank you, "Concerned", for sticking up for our ~rural values~! I'm so tired of people saying selfish things like, "hey, maybe people should be able to live sorta close to where they work" or "where are my childrens' generation going to reside".

If people want to live in our perfect, village-like hamlets they should either:
1) Be absurdly wealthy
2) Get a time machine, already

23 people like this
Posted by Sharkie63
a resident of Woodside: Mountain Home Road
on Mar 17, 2019 at 9:04 pm

Concerned has a point. Woodside/PV are much more rural than Menlo Park, which is much closer to qualifying as high density housing. And the zoning is different there as well. The Bay Area needs to solve its housing crisis, but it’s important we keep the diversity of every neighborhood and not cave to pressure. Woodside and Portol Valley are rural and have always been, and should continue to be.

4 people like this
Posted by Shaking my head
a resident of Portola Valley: other
on Mar 18, 2019 at 2:00 pm

Jeez. All this ordinance does is allow people to use their total square footage as they see fit. Not everyone wants a 10,000 sf house - instead, now they can have 8800 sf house plus a 1200 sf house *if* they haven't already used all their square footage. Do your homework....

9 people like this
Posted by old timer
a resident of Portola Valley: Brookside Park
on Mar 18, 2019 at 4:30 pm

Most of us moved to Portola Valley to get into a more peaceful environment. WE have raised our families here & seen alot of growth - not to mention an increase of traffic. When The Ranch was built we were sorrowful of the hills that had been taken away from us. We watched out kids play little league & soccer at Corte Madera loving every minute we would spend in out comfort zone. Not everyone was rich back then we all just wanted a more serene way of life. Please do not take that away from us !!

Like this comment
Posted by Hector
a resident of Menlo Park: Central Menlo Park
on Mar 19, 2019 at 1:43 pm

Don’t worry Amigo, Portola Valley is decades away from packing them in like sardines Redwood City style.

Like this comment
Posted by TomS
a resident of Atherton: West Atherton
on Mar 19, 2019 at 4:52 pm

I'm pretty sure there are recently passed California senate bill(s) that force all towns in the state to be more flexible with allowing secondary housing (otherwise known as ADUs). Someone can correct me if I'm wrong but I believe any parcel zoned single or multi-family residential in the state technically must be zoned to allow ADUs. Towns can have additional zoning regulations that can limit their size, location, aesthetics, etc but I believe they can not outright outlaw them.

Web Link

Sorry, but further commenting on this topic has been closed.

Stay informed

Get daily headlines sent straight to your inbox.

After experiencing harassment, owner of Zareen's restaurants speaks out about Islamophobia, racism
By Elena Kadvany | 28 comments | 6,171 views

Don't Miss Your Exit (and other lessons from an EV drive)
By Sherry Listgarten | 12 comments | 2,098 views

Goodbye Food Waste!
By Laura Stec | 5 comments | 1,960 views

"Better" Dads and "Re-invigorated" Moms: Happier Couples
By Chandrama Anderson | 0 comments | 1,435 views

Good News: The New Menlo Park Rail Subcommittee Hits A Home Run
By Dana Hendrickson | 11 comments | 1,344 views


Register today!

On Friday, October 11, join us at the Palo Alto Baylands for a 5K walk, 5K run, 10K run or half marathon! All proceeds benefit local nonprofits serving children and families.

Learn More