Skip to content
Bay Area Architect Architects ranked by permits
Who to call firstWho to call

Engineer, San Francisco License C78170

Sia Consulting Corp

The city has issued 229 of the 277 San Francisco building permits that name Sia Consulting Corp since 2018. The work is mostly residential, led by apartments and multifamily. Their median plan-review permit for apartments and multifamily took 17.7 months from filing to issue, 184% slower than the citywide median. Their busiest neighborhoods are Mission, Portola and West of Twin Peaks.

Also filed as
architect, designer, permit expediter
Issued by the city
229 of 277 filed since 2018
Median plan-review time, apartments and multifamily
17.7 mo city median 6.2 mo
Rank for apartments and multifamily
No. 15 of 516 by apartments and multifamily issued
Overall rank
No. 25 of 1,146 engineers

What they work on

Every San Francisco building permit with Sia Consulting Corp on the record since 2018, by project type. Most filed: 95 apartments and multifamily, 90 home remodels, 51 ADUs.

Residential and commercial, by permits filed

92% residential
8% commercial
Permits by project type, filed and issued
  1. Apartments and multifamily Residential 77 of 95 issued 34% of filings.
  2. Home remodels Residential 81 of 90 issued 32% of filings.
  3. ADUs Residential 38 of 51 issued 18% of filings.
  4. Home additions Residential 10 of 11 issued 4% of filings.
  5. New homes Residential 5 of 9 issued 3% of filings.
  6. Hotels, clinics, schools and other commercial Commercial 7 of 8 issued 3% of filings.
  7. Retail and shops Commercial 6 of 7 issued 3% of filings.
  8. Offices Commercial 4 of 4 issued 1% of filings.
  9. Restaurants and bars Commercial 1 of 2 issued 1% of filings.

Permits over time

Permits filed each year, drawn as a street with one building per year, and how many of all their permits the city has issued.

Busiest year
2020
49 permits filed
Latest filing
Oct 2026
83% of 277 issued
Permits filed per year: 2018: 12, 2019: 10, 2020: 49, 2021: 40, 2022: 38, 2023: 34, 2024: 26, 2025: 36, 2026: 32. The 2026 figure runs through October 20, 2026.

One building per year, its height the permits filed. Each floor line marks 10 permits; the 2026 building is dashed because it counts permits filed through October 20, 2026.

Issued by the city: 229 of 277 permits filed

83%

All San Francisco project permits since 2018 in this data

93% issued

48 not issued as of October 20, 2026. Source: SF Department of Building Inspection permits via DataSF.

How fast their permits come through

Filing to issue for permits that went through plan review. Sia Consulting Corp has 135 of those across all project types; the citywide comparison is for apartments and multifamily, their most filed type, where 3,633 of 59,927 permits went through plan review and the rest were approved over the counter.

Sia Consulting Corp, apartments and multifamily

17.7months

That is 184% slower than the citywide median for apartments and multifamily.

Median months from filing to issue for plan-review permits. Sia Consulting Corp, apartments and multifamily: 17.7 months. San Francisco, apartments and multifamily: 6.2 months. Middle half of city permits: 2.7 to 12.3 months.
17.7 months for apartments and multifamily, faster than 13 of 106 other engineers ranked for apartments and multifamily that have a median for it Each circle is a firm's median for its plan-review permits for apartments and multifamily. Dashed line: the median of all San Francisco plan-review permits for apartments and multifamily, 6.2 months. Shaded: the middle half of those permits, 2.7 to 12.3 months.
0 3 6 9 12 15 18 21+ months Unicorn Consulting: 9.0 months Ecr Engineering: 4.1 months Double D Engineering: 10.8 months Altos Engineering: 4.4 months Atrium Structural Engineer: 12.8 months Rs Engineering: 17.9 months Enertia Designs: 13.9 months Lawrence Liao Str. Eng: 8.5 months Mercury Engineering Group: 9.4 months Ice Design Inc.: 17.9 months Kevin O'connor Inc.: 5.2 months Innovative Const: 20.2 months Design Consultants Group, Inc: 9.4 months Mhc Engineers: 5.0 months Murphy Burr Curry Inc.: 6.9 months Hom & Pisano Engineering Inc.: 8.3 months Base Design: 13.1 months One Design: 17.3 months Erwin O'toole: 4.8 months Rei Build Up Design: 11.9 months W. Charles Perry & Assoc.: 20.1 months Yuflux Engineering Llc.: 8.1 months Acies Engineering: 3.4 months Kung Kay Chiu: 1.2 months Zfa Structural Engineers: 8.5 months Hcg Associates, Inc.: 13.3 months Telesis: 6.1 months Doug Lee: 22.9 months Q Architecture: 12.2 months Streamline Engineering: 5.3 months Nabi Const. & Engineering: 3.4 months Bkf Engineers: 13.5 months Smith Engineering, Inc.: 9.4 months Ftf Engineering Inc.: 4.6 months Degenkolb Engineers: 7.6 months Acg Engineers Inc: 6.8 months Kpff: 10.1 months Ny Engineering Consulting: 14.8 months Simpson Gumpertz & Heger: 13.2 months Dci Engineers: 3.5 months Semco Engineering Inc.: 9.7 months Ashley & Vance Engineering: 9.2 months Edesignc Incorporated: 7.5 months Sergio Mayorga Assc: 31.8 months Mk Engineers Inc.: 12.7 months Engineering 350: 5.8 months A & J Design Associates Inc.: 9.2 months Interlocity: 5.6 months Dolmen Structural Engineer: 5.5 months Smw Associates: 26.1 months Access System & Solutions Inc: 7.8 months Bahman Ghassenmzadeh: 11.4 months Dominguez Associates: 13.3 months Wmstructural: 6.7 months Holmes Culley: 6.1 months Aj Miller And Associates: 2.8 months Interface Engineering: 3.3 months Emerald City: 5.9 months Thomas Podesta Engineer: 30.9 months Hohbach-Lewin, Inc: 13.1 months Soha Engineers: 9.8 months Optimal Design Group: 18.5 months Imeg: 6.5 months Spi Consulting Engineers, Inc.: 11.2 months Julia Y. Chen Design Inc.: 2.2 months Luk And Associates: 6.3 months Integrand Structural Engineer: 13.4 months Duquette Engineering: 8.5 months Kpff Consulting Engineers: 4.5 months S & P Structural Engineers: 33.0 months Framework Engineering: 11.9 months Lx Engineering: 6.8 months Pae: 8.8 months Powell And Associates: 16.6 months Tipping-Mar Structural Eng: 6.5 months Geissler Engineering: 46.9 months D H Charles: 2.2 months Urban Design Consulting Eng: 6.5 months Tommy Siu & Associates: 7.7 months Hc Structural Engineering Inc: 4.3 months Tuan & Robinson Str. Engineer: 8.4 months Gregory Miller Structural Eng.: 8.4 months Drill Tech: 2.8 months Meyers+Engineers: 5.2 months Bay City Mechanical Inc.: 10.4 months Jaime Neilson, P.E., S.E: 4.5 months Trylon Tsf: 5.6 months Edward C. Robinson, Pe: 4.9 months Brierley Associates: 2.7 months Mcginnis & Assoc Consulting: 8.2 months O'brien Mechanical Inc Ii: 6.5 months W.H.Yang Structural Engr: 30.1 months Ficcadenti Waggonen & Castle: 2.8 months Nishkian Menninger: 2.2 months J.W. Mcclenahan Co.: 19.9 months Nexius Solutions Inc: 10.3 months Tuan & Robinson Structural: 4.3 months Condon - Johnson & Assoc.: 8.7 months Calvin Abshier: 14.1 months Craig M. Horner: 17.0 months Desmond Blake: 0.9 months Earthbound: 8.9 months Rde Structural Engineering: 5.6 months Zeiger Engineers Inc.: 13.8 months Wm Tucker Associates: 3.0 months Gary L Hennings: 13.9 months Sia Consulting Corp 0 3 6 9 12 15 18 21+ months Unicorn Consulting: 9.0 months Ecr Engineering: 4.1 months Double D Engineering: 10.8 months Altos Engineering: 4.4 months Atrium Structural Engineer: 12.8 months Rs Engineering: 17.9 months Enertia Designs: 13.9 months Lawrence Liao Str. Eng: 8.5 months Mercury Engineering Group: 9.4 months Ice Design Inc.: 17.9 months Kevin O'connor Inc.: 5.2 months Innovative Const: 20.2 months Design Consultants Group, Inc: 9.4 months Mhc Engineers: 5.0 months Murphy Burr Curry Inc.: 6.9 months Hom & Pisano Engineering Inc.: 8.3 months Base Design: 13.1 months One Design: 17.3 months Erwin O'toole: 4.8 months Rei Build Up Design: 11.9 months W. Charles Perry & Assoc.: 20.1 months Yuflux Engineering Llc.: 8.1 months Acies Engineering: 3.4 months Kung Kay Chiu: 1.2 months Zfa Structural Engineers: 8.5 months Hcg Associates, Inc.: 13.3 months Telesis: 6.1 months Doug Lee: 22.9 months Q Architecture: 12.2 months Streamline Engineering: 5.3 months Nabi Const. & Engineering: 3.4 months Bkf Engineers: 13.5 months Smith Engineering, Inc.: 9.4 months Ftf Engineering Inc.: 4.6 months Degenkolb Engineers: 7.6 months Acg Engineers Inc: 6.8 months Kpff: 10.1 months Ny Engineering Consulting: 14.8 months Simpson Gumpertz & Heger: 13.2 months Dci Engineers: 3.5 months Semco Engineering Inc.: 9.7 months Ashley & Vance Engineering: 9.2 months Edesignc Incorporated: 7.5 months Sergio Mayorga Assc: 31.8 months Mk Engineers Inc.: 12.7 months Engineering 350: 5.8 months A & J Design Associates Inc.: 9.2 months Interlocity: 5.6 months Dolmen Structural Engineer: 5.5 months Smw Associates: 26.1 months Access System & Solutions Inc: 7.8 months Bahman Ghassenmzadeh: 11.4 months Dominguez Associates: 13.3 months Wmstructural: 6.7 months Holmes Culley: 6.1 months Aj Miller And Associates: 2.8 months Interface Engineering: 3.3 months Emerald City: 5.9 months Thomas Podesta Engineer: 30.9 months Hohbach-Lewin, Inc: 13.1 months Soha Engineers: 9.8 months Optimal Design Group: 18.5 months Imeg: 6.5 months Spi Consulting Engineers, Inc.: 11.2 months Julia Y. Chen Design Inc.: 2.2 months Luk And Associates: 6.3 months Integrand Structural Engineer: 13.4 months Duquette Engineering: 8.5 months Kpff Consulting Engineers: 4.5 months S & P Structural Engineers: 33.0 months Framework Engineering: 11.9 months Lx Engineering: 6.8 months Pae: 8.8 months Powell And Associates: 16.6 months Tipping-Mar Structural Eng: 6.5 months Geissler Engineering: 46.9 months D H Charles: 2.2 months Urban Design Consulting Eng: 6.5 months Tommy Siu & Associates: 7.7 months Hc Structural Engineering Inc: 4.3 months Tuan & Robinson Str. Engineer: 8.4 months Gregory Miller Structural Eng.: 8.4 months Drill Tech: 2.8 months Meyers+Engineers: 5.2 months Bay City Mechanical Inc.: 10.4 months Jaime Neilson, P.E., S.E: 4.5 months Trylon Tsf: 5.6 months Edward C. Robinson, Pe: 4.9 months Brierley Associates: 2.7 months Mcginnis & Assoc Consulting: 8.2 months O'brien Mechanical Inc Ii: 6.5 months W.H.Yang Structural Engr: 30.1 months Ficcadenti Waggonen & Castle: 2.8 months Nishkian Menninger: 2.2 months J.W. Mcclenahan Co.: 19.9 months Nexius Solutions Inc: 10.3 months Tuan & Robinson Structural: 4.3 months Condon - Johnson & Assoc.: 8.7 months Calvin Abshier: 14.1 months Craig M. Horner: 17.0 months Desmond Blake: 0.9 months Earthbound: 8.9 months Rde Structural Engineering: 5.6 months Zeiger Engineers Inc.: 13.8 months Wm Tucker Associates: 3.0 months Gary L Hennings: 13.9 months Sia Consulting Corp

7 firms with medians over 21 months are drawn at the right edge.

Where they rank

Ranked by permits the city has issued since 2018, first across every project type, then for apartments and multifamily alone.

  1. 23 Zfa Structural Engineers 244
  2. 24 One Design 237
  3. 25 Sia Consulting Corp 229
  4. 26 Murphy Burr Curry Inc. 226
  5. 27 Design Everest Consulting 226

All permits issued, 1,146 engineers Full ranking

  1. 13 Innovative Const 79
  2. 14 Design Consultants Group, Inc 77
  3. 15 Sia Consulting Corp 77
  4. 16 Mhc Engineers 75
  5. 17 Murphy Burr Curry Inc. 75

Apartments and multifamily issued, 516 engineers

Where they work

The neighborhoods where Sia Consulting Corp files the most permits, and how many engineers count each one among their top 4 neighborhoods.

  1. 01 Mission 298 engineers count Mission among their busiest neighborhoods
  2. 02 Portola 20 engineers count Portola among their busiest neighborhoods
  3. 03 West of Twin Peaks 234 engineers count West of Twin Peaks among their busiest neighborhoods
  4. 04 Castro/Upper Market 141 engineers count Castro/Upper Market among their busiest neighborhoods

Questions for the first call

  1. Which of your recent San Francisco permits are closest to my project in type, size and neighborhood, and can I see the permit numbers?
  2. How long did those permits take from filing to issue, and what did plan check send back?
  3. Who on your team draws the set, who stamps it, and who answers the city's comments?

Other engineers for apartments and multifamily

Firms ranked near Sia Consulting Corp by permits issued for apartments and multifamily.

  1. 12 Kevin O'connor Inc. 82 apartments and multifamily issued · 5.2 mo median for apartments and multifamily
  2. 13 Innovative Const 79 apartments and multifamily issued · 20.2 mo median for apartments and multifamily
  3. 14 Design Consultants Group, Inc 77 apartments and multifamily issued · 9.4 mo median for apartments and multifamily
  4. 16 Mhc Engineers 75 apartments and multifamily issued · 5.0 mo median for apartments and multifamily
  5. 17 Murphy Burr Curry Inc. 75 apartments and multifamily issued · 6.9 mo median for apartments and multifamily
  6. 18 Hom & Pisano Engineering Inc. 61 apartments and multifamily issued · 8.3 mo median for apartments and multifamily
Sheet
S-025 No. 25 of 1,146
Drawing
Permit record, Sia Consulting Corp
Engineer, San Francisco
License
C78170 check with BPELSG
Data as of
Oct 2026
Scale
Not to scale

Built only from public San Francisco Department of Building Inspection records (permits, permit contacts), updated 2026-10-20. It is not a review or an endorsement, and Sia Consulting Corp has not paid to be listed. Project addresses are never shown.

Is this your firm? Claim it or send a correction.