Forest Hill Extension, San Francisco: Homes & Real Estate Guide
Forest Hill Extension is the neighborhood south of Dewey Boulevard, between Forest Hill and Portola Drive, that rises east onto Edgehill Mountain. It is subdistrict 4J in the MLS’s District 4, sometimes also called Laguna Honda. The Assessor’s 2025 roll lists 616 single-family houses among its 685 parcels.
San Francisco Planning’s residence parks study groups it with Forest Hill as a single 1912 development, but the two differ in ways that matter to an owner: the Extension holds every block of the city’s Edgehill Mountain Slope Protection Area, and its houses run a little later and smaller.
Forest Hill Extension homes for sale
Forest Hill Extension market report
Where the Extension sits
Dewey Boulevard is the northern line, and Wikipedia’s Forest Hill article describes the area south of it as Laguna Honda or the Forest Hill Extension. On the Assessor’s roll, its addresses run along Ulloa Street (the longest run, about 110 parcels), Idora, Hernandez, Merced, Vasquez, Rockaway, Balceta and Garcia avenues, Edgehill Way, Rockwood Court, Kensington, Sydney and Woodside ways, and parts of Laguna Honda Boulevard, Portola Drive and Dewey Boulevard.
Its neighbors are Forest Hill to the north, West Portal to the west along Ulloa Street, St. Francis Wood across Portola Drive to the southwest, and Miraloma Park and Sherwood Forest to the east and southeast. The Laguna Honda Hospital campus nearby is listed by Planning as eligible for the National and California Registers.
Edgehill Mountain and the slope protection area
This is the Extension’s defining rule. DBI’s slope protection page names an Edgehill Mountain Slope Protection Area made up of Assessor blocks 2875, 2876, 2923, 2933, 2934, 2935, 2936A and 2936B. On the 2025 roll, all eight blocks, about 176 parcels, sit in subdistrict 4J.
On those blocks, and on any lot touching a state earthquake-induced landslide zone or averaging steeper than 4 horizontal to 1 vertical, these projects trigger the rules:
- new buildings with more than 1,000 square feet of new projected roof area;
- additions totaling more than 500 square feet of new projected roof area;
- shoring, underpinning, or grading of more than 50 cubic yards of earth;
- other work that could substantially affect slope stability.
The owner submits a Slope Protection Checklist stamped by a California-licensed engineer or architect. DBI then assigns a review tier, which can mean a third-party panel of geotechnical and structural engineers or a public Structural Advisory Committee review, both paid for by the applicant. DBI’s page lists the eight Edgehill Mountain blocks by number under its Structural Advisory Committee review, so ask DBI early which tier a project there will get.
Planning’s landslide layer also shows a mapped zone along Edgehill Way. Its liquefaction layer shows none in the Extension. See our San Francisco hazard maps page for how to check a parcel.
The houses, in Assessor figures
The median recorded build year for the 616 single-family parcels is 1931, three years later than Forest Hill’s. About 47 percent were built before 1930 and about 27 percent after 1945, so 1920s and 1930s houses share the streets with postwar ones, especially on the higher ground.
The median single-family lot is about 3,508 square feet and the median building area about 1,792 square feet, against roughly 3,998 and 2,332 in Forest Hill. The roll also lists 22 vacant residential parcels, a reason to check whether a house is sold with an adjoining lot.
Almost all parcels, about 656, are zoned RH-1(D) in the Assessor’s zoning field. Planning maps the Family and Senior Housing Opportunity SUD here as well, which can allow two to four units on a qualifying RH lot; on Edgehill blocks, a project of that size could also trigger slope protection review.
Historic status
Planning’s eligible Forest Hill Historic District, period of significance 1912–1939, is mapped mostly to the north. Check whether a particular Extension house near Dewey Boulevard falls inside its outline before planning major exterior work.
Outside that district, Planning’s Register layers show no historic district covering the Extension. Individual older houses can still be evaluated as historic resources when a project is proposed.
Getting around
Forest Hill station sits at Laguna Honda and Dewey boulevards, at the Extension’s northern edge, with K, L and M service in the Twin Peaks Tunnel. West Portal station is where Ulloa Street meets West Portal Avenue.
The 36 Teresita and 52 Excelsior buses start at Forest Hill station, per route lists from 2022. On Edgehill’s upper streets, the walk down to either station can be steep, so test it before you buy.
Selling a home in Forest Hill Extension
Buyers here sort houses first by ground: a level lot on Ulloa or Merced is a different purchase from a view lot on Edgehill Way. Prepare the records that answer those questions before listing.
- Slope status. Confirm whether the lot is on an Edgehill block, in a mapped landslide zone or both, and disclose it.
- Engineering file. Gather any geotechnical, foundation, retaining-wall or drainage reports and the permits that went with them.
- Additions. Show permits for any added rooms or decks; a buyer planning more will ask what review the last project needed.
- Title. Check the recorded restrictions and whether any adjoining parcel conveys with the house.
- City requirements. See our San Francisco selling requirements guide for the 3R report and other sale rules.
Diamond may refer you to partners we work with, such as engineers and inspectors; you’re free to choose any provider. Our Natural Hazard Disclosure report guide explains what buyers will receive.
Questions people ask
Is Forest Hill Extension part of Forest Hill?
Historically, yes: Planning’s residence parks study groups Forest Hill and Forest Hill Extension together as a 1912 development. The MLS and the Assessor treat them as separate subdistricts, 4C and 4J.
What is the Edgehill Mountain Slope Protection Area?
It is a set of eight Assessor blocks where larger building, addition and grading projects need a stamped slope checklist and may get third-party or Structural Advisory Committee review. All eight blocks are in Forest Hill Extension.
Which Muni station is closest?
Forest Hill station, at Laguna Honda and Dewey boulevards, for most of the neighborhood; West Portal station for blocks toward the western end of the neighborhood’s stretch of Ulloa Street.
Can I add a unit to a house in Forest Hill Extension?
Possibly. The lots are mostly RH-1(D) inside the city’s Family and Senior Housing Opportunity SUD, but slope protection, historic review and recorded restrictions can all apply. Check the specific lot with Planning and DBI.
Are houses in the Extension older or newer than in Forest Hill?
Slightly newer on average: a median build year of 1931 against 1928, with a larger share of postwar houses.
Planning a sale in Forest Hill Extension? Request a home valuation, or read how we sell San Francisco homes. The San Francisco guide covers the citywide picture.
Sources & notes
- SF.gov / Department of Building Inspection: Comply with slope protection requirements for your building project
- DataSF / SF Assessor-Recorder: Assessor Historical Secured Property Tax Rolls, 2025 closed roll (parcel counts by class, build years, median lot and building area, zoning codes and street lists for subdistricts 4A-4T; queried October 2026)
- San Francisco Planning: PlanningData map service (zoning districts, height districts, special use districts, landmarks, National and California Register historic districts, Article 10 districts, seismic hazard zones; queried October 2026)
- San Francisco Planning: Residence Parks Historic Context Statement
- Wikipedia: Forest Hill, San Francisco
- Wikipedia: Twin Peaks Tunnel
- Wikipedia: List of San Francisco Municipal Railway lines (route termini; page states service as of July 2022)
- San Francisco Planning Code (via GoCodebook): Sec. 249.94, Family and Senior Housing Opportunity Special Use District
- California Geological Survey: Seismic Hazards Program
- San Francisco Association of REALTORS: MLS district map (2001 edition, via Reineck & Reineck)
Last reviewed October 2026 by Matthew Martinez.
