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Engineer, Irving License C90242

Trylon

The city has issued 11 of the 17 San Francisco building permits that name Trylon since 2018. The work is a mix of residential and commercial, led by apartments and multifamily. Their median plan-review permit, across all project types, took 4.5 months from filing to issue. Their busiest neighborhoods are Bayview Hunters Point, Mission and Sunset/Parkside.

Also filed as
architect
Issued by the city
11 of 17 filed since 2018
Median plan-review time, all types
4.5 mo filing to issue
Rank for apartments and multifamily
No. 290 of 516 by apartments and multifamily issued
Overall rank
No. 372 of 1,146 engineers

What they work on

Every San Francisco building permit with Trylon on the record since 2018, by project type. Most filed: 6 apartments and multifamily, 6 offices, 4 hotels, clinics, schools and other commercial.

Residential and commercial, by permits filed

35% residential
65% commercial
Permits by project type, filed and issued
  1. Apartments and multifamily Residential 4 of 6 issued 35% of filings.
  2. Offices Commercial 4 of 6 issued 35% of filings.
  3. Hotels, clinics, schools and other commercial Commercial 3 of 4 issued 24% of filings.
  4. Restaurants and bars Commercial 0 of 1 issued 6% 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
7 permits filed
Latest filing
May 2024
65% of 17 issued
Permits filed per year: 2018: 0, 2019: 0, 2020: 7, 2021: 4, 2022: 1, 2023: 3, 2024: 2, 2025: 0, 2026: 0. The 2026 figure runs through October 20, 2026.

One building per year, its height the permits filed. Each floor line marks 1 permit; the 2026 building is dashed because it counts permits filed through October 20, 2026.

Issued by the city: 11 of 17 permits filed

65%

All San Francisco project permits since 2018 in this data

93% issued

6 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. Trylon has 3 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.

Trylon, all project types

4.5months

Median months from filing to issue for plan-review permits. Trylon, all project types: 4.5 months. San Francisco, apartments and multifamily: 6.2 months. Middle half of city permits: 2.7 to 12.3 months.
107 other engineers ranked for apartments and multifamily have a median for it; Trylon has fewer than 3 issued plan-review permits for apartments and multifamily with usable dates 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 Sia Consulting Corp: 17.7 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 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 Sia Consulting Corp: 17.7 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

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. 370 Structus 12
  2. 371 Teh Cbr Group, Inc. 12
  3. 372 Trylon 11
  4. 373 Emc2 Structural Design Inc. 11
  5. 374 Tranvu Llc 11

All permits issued, 1,146 engineers Full ranking

  1. 288 Nishkian Menninger 4
  2. 289 Structural Eng.Collaborative 4
  3. 290 Trylon 4
  4. 291 Adept Construction 4
  5. 292 J.W. Mcclenahan Co. 4

Apartments and multifamily issued, 516 engineers

Where they work

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

  1. 01 Bayview Hunters Point 149 engineers count Bayview Hunters Point among their busiest neighborhoods
  2. 02 Mission 298 engineers count Mission among their busiest neighborhoods
  3. 03 Sunset/Parkside 220 engineers count Sunset/Parkside among their busiest neighborhoods
  4. 04 Nob Hill 94 engineers count Nob Hill 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 Trylon by permits issued for apartments and multifamily.

  1. 284 P&D Engineering Solutions 4 apartments and multifamily issued
  2. 288 Nishkian Menninger 4 apartments and multifamily issued · 2.2 mo median for apartments and multifamily
  3. 289 Structural Eng.Collaborative 4 apartments and multifamily issued
  4. 292 J.W. Mcclenahan Co. 4 apartments and multifamily issued · 19.9 mo median for apartments and multifamily
  5. 293 Nexius Solutions Inc 4 apartments and multifamily issued · 10.3 mo median for apartments and multifamily
  6. 294 John Yadegar Structural Eng. 4 apartments and multifamily issued
Sheet
S-372 No. 372 of 1,146
Drawing
Permit record, Trylon
Engineer, Irving
License
C90242 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 Trylon has not paid to be listed. Project addresses are never shown.

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