From architect-skills
Provides US building code, structural, fire, accessibility, and energy code references across all 50 states. Invoke for IBC, IRC, NFPA, ADA, ASCE 7, LEED, or state-specific amendments like Title 24, NYC BC, or Florida Building Code.
How this skill is triggered — by the user, by Claude, or both
Slash command
/architect-skills:country-usaThe summary Claude sees in its skill listing — used to decide when to auto-load this skill
Architectural code and regulatory reference for projects within any US state, territory, or D.C. Activate this skill on any US city/state reference, USD currency, square feet / imperial units, mention of "IBC"/"IRC"/"IECC"/"NFPA"/"ASCE 7"/"ADA"/"Title 24"/"CalGreen"/"NYC BC", state building department/AHJ references, or LEED/ENERGY STAR.
Architectural code and regulatory reference for projects within any US state, territory, or D.C. Activate this skill on any US city/state reference, USD currency, square feet / imperial units, mention of "IBC"/"IRC"/"IECC"/"NFPA"/"ASCE 7"/"ADA"/"Title 24"/"CalGreen"/"NYC BC", state building department/AHJ references, or LEED/ENERGY STAR.
The US operates as Archetype B (National Model + State/Local Adoption) with significant local variation. There is no federal building code; the Authority Having Jurisdiction (AHJ) -- which may be the city, county, state, or special district -- decides which model code edition is in force and with what amendments.
LEVEL 1 -- MODEL CODE PUBLISHERS (no enforcement authority)
International Code Council (ICC) -- IBC, IRC, IECC, IFC, IPC, IMC, IFGC, IEBC, IgCC, IWUIC
National Fire Protection Association (NFPA) -- NFPA 101, 70, 13, 72, 285, 5000
ASHRAE -- 90.1, 62.1, 55, 169, 189.1
ASCE -- 7, 41
ACI -- 318, 530, etc.
AISC -- 360, 341, 358, 360
AWS -- D1.1, D1.5
AWC -- NDS, SDPWS
TMS -- 402/602 masonry
ANSI -- A117.1 accessibility, others
ASTM -- material/test standards
LEVEL 2 -- FEDERAL APPLICABILITY (specific contexts)
ADA 2010 Standards (Department of Justice) -- enforcement civil rights
ABA Standards (GSA) -- federal facilities + recipients of federal funds
Fair Housing Act design + construction (HUD) -- residential
HUD Section 504 -- recipients of HUD funds
IRS Energy Tax Credit (179D, 45L) -- referenced ASHRAE 90.1
GSA P100 -- federal facilities standard
DOD UFC -- military facilities
NPS -- National Park Service properties
LEVEL 3 -- STATE
State Building Code Council / DOR / Construction Department adopts model code edition
+ state amendments (e.g., California Building Standards Commission - Title 24)
State Energy Office -- often state energy code (e.g., WA Energy Code)
State Fire Marshal -- often state fire code
State Architectural Access Board (e.g., Massachusetts MAAB)
State Department of Health -- hospital codes (FGI Guidelines often adopted)
State Department of Education -- school facility codes (CHPS, varies)
LEVEL 4 -- LOCAL AHJ
City/County Building Department (Department of Buildings NYC, LADBS LA, etc.)
+ adopted code + local amendments
Fire Marshal
Public Works (right-of-way, utility connections)
Planning Department (zoning, design review)
Historic Preservation Commission (HPC) -- if in historic district
LEVEL 5 -- SPECIAL DISTRICTS
School districts (own facility standards)
Transit authorities (own design criteria)
Universities/medical centers (often own building standards)
Master-planned communities (HOA design review)
Tribal authorities (sovereign on reservation land)
| State | IBC Adopted | IECC Adopted | Notable Amendments |
|---|---|---|---|
| California | 2021 (with CA Title 24) | Title 24 Part 6 (own energy code) | Title 24 Parts 1-12; CALGreen Part 11; Tier 1/2 reach codes; Strong fire (WUI); seismic Cat C+ |
| Texas | 2018-2021 varies by city (no statewide adoption) | 2015-2021 varies; mandatory through DSHS/SECO | Local amendments significant; Houston, Austin, Dallas distinct |
| Florida | FBC 2023 (own custom code; IBC 2021-derived) | FBC Energy Conservation 2023 | High-Velocity Hurricane Zone (HVHZ) for Miami-Dade/Broward; wind speeds 175 mph 0.4% |
| New York | NYS UBC 2020 + NYC has separate (NYC BC 2022 + 1968 grandfather + 2014 commercial) | NYS Energy Code 2020 (90.1-2019 + adds) | NYC has own zoning (Zoning Resolution 1961+amendments), NYC plumbing, NYC mechanical, NYC fuel gas |
| Illinois | No statewide; Chicago has Chicago Construction Codes 2019 (IBC-based) | -- | Chicago strict |
| Massachusetts | 9th Edition (2023, IBC 2021-derived) + amendments | Stretch Energy Code 2023 | Mass MAAB Accessibility ahead of ADA |
| Pennsylvania | UCC IBC 2018 (transitioning to 2021) | IECC 2018 (transitioning) | -- |
| Washington | WSBC 2021 (IBC 2021-derived) | WSEC 2021 (own, most stringent in US) | Seattle Energy Code stricter still |
| Oregon | OSSC 2022 (IBC 2021-derived) | Oregon Energy Code | -- |
| Colorado | No statewide; municipal | -- | Denver/Boulder strict |
| Arizona | No statewide; municipal | -- | -- |
| Georgia | IBC 2018 statewide | IECC 2015 (lags) | -- |
| Michigan | MBC 2015 (transitioning 2021) | MUEC 2015 | -- |
| Ohio | OBC 2017 (transitioning 2024) | -- | -- |
| North Carolina | NCBC 2018 + Local | NCECC | -- |
| Virginia | USBC 2018 (transitioning 2021) | VUSBC | -- |
ALWAYS verify current adoption status with the specific AHJ. ICC publishes a state-by-state matrix, but adoption can lag by years and local amendments significantly modify.
| Group | Description | Subdivisions |
|---|---|---|
| A | Assembly | A-1 (theatres, concert halls), A-2 (food/drink est), A-3 (worship, lectures, exhibits), A-4 (indoor sport), A-5 (outdoor) |
| B | Business | (offices, professional services, banks, post offices, etc.) |
| E | Educational | (through 12th grade -- university is B or A) |
| F | Factory/Industrial | F-1 (moderate hazard), F-2 (low hazard) |
| H | High Hazard | H-1 (detonation), H-2 (deflagration/accelerated burning), H-3 (oxidizers, combustibles), H-4 (toxic), H-5 (semiconductor fab) |
| I | Institutional | I-1 (supervised personal care), I-2 (hospitals/nursing), I-3 (detention -- I-3.1-5 by escape ability), I-4 (daycare) |
| M | Mercantile | (retail, shopping centers, etc.) |
| R | Residential | R-1 (transient -- hotel/motel), R-2 (multi-family >2 dwelling units, not transient), R-3 (1-2 family, not classified as R-1/2/4), R-4 (small assisted living 6-16 residents) |
| S | Storage | S-1 (moderate hazard), S-2 (low hazard) |
| U | Utility / misc | (sheds, fences, retaining walls, agricultural buildings) |
| Type | Description | Frame Fire Rating | Ext. Bearing Walls | Floor | Roof |
|---|---|---|---|---|---|
| IA | Non-combustible fire-resistive | 3 hr | 3 hr | 2 hr | 1.5 hr |
| IB | Non-combustible fire-resistive | 2 hr | 2 hr | 2 hr | 1 hr |
| IIA | Non-combustible protected | 1 hr | 1 hr | 1 hr | 1 hr |
| IIB | Non-combustible unprotected | 0 hr | 0 hr | 0 hr | 0 hr |
| IIIA | Exterior non-combustible bearing + protected combustible | 1 hr | 2 hr | 1 hr | 1 hr |
| IIIB | Same as IIIA but unprotected | 0 hr | 2 hr | 0 hr | 0 hr |
| IV-HT | Heavy Timber (legacy, large members) | HT | 2 hr | HT | HT |
| IV-A | Mass Timber (new in IBC 2021) up to 18 storeys | 3 hr fully encapsulated | 3 hr | 2 hr | 1.5 hr |
| IV-B | Mass Timber up to 12 storeys, partial exposure | 2 hr partially encapsulated | 2 hr | 2 hr | 1 hr |
| IV-C | Mass Timber up to 9 storeys, fully exposed | 2 hr exposed | 2 hr | 2 hr | 1 hr |
| VA | Protected combustible (e.g., light wood frame) | 1 hr | 1 hr | 1 hr | 1 hr |
| VB | Unprotected combustible | 0 hr | 0 hr | 0 hr | 0 hr |
A critical IBC table: maximum building height in storeys, height in feet, and area per storey by Occupancy Group + Construction Type. Sprinklers permit increases. Frontage area increase per Section 506.3. The table is too large to fully reproduce; key benchmarks:
| Combination | Max Storeys (sprinklered) | Max Ht (ft) | Max Area/Storey (sf) |
|---|---|---|---|
| B (office) Type IA | 12 (unlimited area) | unlimited | unlimited |
| B Type IB | 12 | 180 | unlimited |
| B Type IIA | 6 | 85 | 92,500 |
| B Type IIB | 5 | 75 | 69,000 |
| B Type IIIA | 6 | 85 | 57,500 |
| R-2 Type IIA | 5 | 75 | 36,000 |
| R-2 Type IV-A (mass timber) | 18 | 270 | 108,000 |
| R-2 Type IV-B | 12 | 180 | 72,000 |
| R-2 Type IV-C | 8 | 85 | 36,000 |
| M (mercantile) Type IIB | 5 | 75 | 87,500 |
| Parameter | Value |
|---|---|
| Min corridor width (>=50 occupants) | 44 in (1118 mm) |
| Min corridor width (<50 occupants) | 36 in (914 mm) |
| Min stair width (occupant load > 50) | 44 in (1118 mm) |
| Stair capacity unsprinklered | 0.3 in/person (7.62 mm) |
| Stair capacity sprinklered | 0.2 in/person (5.08 mm) |
| Min door clear width | 32 in (813 mm) |
| Max travel distance (B sprinklered) | 300 ft (91.4 m) |
| Max travel distance (B unsprinklered) | 200 ft (60.96 m) |
| Max travel distance (I-2 sprinklered) | 200 ft (60.96 m) |
| Max common path of travel (B sprinklered) | 100 ft (30.48 m) |
| Max common path of travel (B unsprinklered) | 75 ft (22.86 m) |
| Max dead-end (B sprinklered) | 50 ft (15.24 m) |
| Max dead-end (R sprinklered) | 50 ft |
US uses both IFC (model fire code, ICC) and NFPA 101 Life Safety Code 2024 as supplementary. In some states, NFPA 101 is the primary (e.g., MA, hospitals nationally adopt NFPA 99 + 101). Check AHJ.
NFPA 13:2025 (or current adopted) -- the design standard for sprinkler systems. Hazard classes Light, Ordinary 1-2, Extra 1-2. Density-area method.
The test method for combustible components in non-combustible wall assemblies. Often required for foam-insulated walls of Type I-IV buildings. Post-Grenfell-like incidents in US (Chicago 2010s, Las Vegas) drove tightening.
Although not in IBC, the Facility Guidelines Institute (FGI) Guidelines for Design and Construction of Hospitals 2022 is adopted by most state health departments as enforceable for hospital projects. Critical for room sizes, clearances, infection control.
US uses two parallel energy code regimes:
8 zones (1-8) + moisture sub-zones (A humid, B dry, C marine). Examples:
| Zone | City | Description |
|---|---|---|
| 1A | Miami | Very Hot Humid |
| 2A | Houston, Atlanta (margin), Orlando | Hot Humid |
| 2B | Phoenix, Tucson | Hot Dry |
| 3A | Memphis, Atlanta | Warm Humid |
| 3B | Los Angeles, Bakersfield | Warm Dry |
| 3C | San Francisco | Warm Marine |
| 4A | Washington DC, Philadelphia, NYC | Mixed Humid |
| 4B | Albuquerque | Mixed Dry |
| 4C | Seattle, Portland OR | Mixed Marine |
| 5A | Chicago, Boston, Detroit | Cool Humid |
| 5B | Denver | Cool Dry |
| 6A | Minneapolis | Cold Humid |
| 7 | International Falls MN, Anchorage | Very Cold |
| 8 | Fairbanks, Northern Alaska | Subarctic |
| Zone | Wall (Non-Res) | Roof | Floor | Window U | Window SHGC |
|---|---|---|---|---|---|
| 1 | 0.81 | 0.27 | -- (no req for non-cond) | 5.0 | 0.25 |
| 2 | 0.66 | 0.22 | -- | 3.7 | 0.25 |
| 3 | 0.51 | 0.22 | 1.06 | 2.7 | 0.25 |
| 4 | 0.42 | 0.22 | 0.65 | 2.4 | 0.40 |
| 5 | 0.34 | 0.20 | 0.48 | 2.0 | 0.40 |
| 6 | 0.31 | 0.18 | 0.43 | 1.7 | 0.40 |
| 7 | 0.25 | 0.17 | 0.39 | 1.6 | NR |
| 8 | 0.20 | 0.15 | 0.35 | 1.4 | NR |
Mandatory green building code for California. Categories include water reduction, low-VOC materials, construction waste diversion, EV charging readiness. Two voluntary tiers above mandatory baseline.
Referenced by IBC Chapter 11. Most state codes apply ANSI A117.1-2017 (current edition; A117.1-2009 still in effect in some jurisdictions). 2017 edition adds Adult Changing Stations, expanded reach ranges.
| Element | Dimension |
|---|---|
| Accessible route | 36 in (914 mm) clear; 60 in (1525 mm) passing space every 200 ft |
| Door clear width | 32 in (813 mm) |
| Ramp slope | 1:12 max (8.33%); 1:20 preferred (5%) for tactile contrast |
| Ramp landing | 60 in (1525 mm) square; every 30 in (762 mm) rise |
| Cross slope | 1:48 max (2%) |
| Lift cabin (passenger) | 51 x 68 in (1295 x 1727 mm) -- centred-opening Type B |
| Lift cabin (Type A side-opening) | 54 x 80 in (1372 x 2032 mm) |
| Accessible WC stall | 60 x 56 in (1525 x 1422 mm) wheelchair stall |
| Accessible WC water closet | side reach 16-18 in (406-457 mm), centerline 18 in from wall |
| Lavatory | knee clear 27 in (686 mm); rim 34 in (864 mm) max |
| Accessible parking | 8 ft (2440 mm) wide stall + 5 ft (1525 mm) aisle (standard); 11 ft + 5 ft (van) |
| Van-accessible parking | 8 ft (2440 mm) + 8 ft (2440 mm) aisle (alt config) |
| Reach -- forward unobstructed | 15 in (380) low, 48 in (1220) high |
| Reach -- side unobstructed | 15 in (380) low, 48 in (1220) high |
For 4+ unit residential, FHA requires:
FHA covers all 4+ unit residential built for first occupancy after March 1991.
The single most-referenced US structural standard. Maps for:
Current edition. Distinct chapters for SDC A-F detailing.
Current AISC unified specification (ASD + LRFD).
National Design Specification (NDS) for wood construction. SDPWS for wood diaphragms/shear walls. Mass timber (CLT, GLT) provisions integrated.
Current edition. Reinforced and unreinforced.
NYC has its own building code (not IBC-derived directly; chapters renumbered). NYC BC 2022 is current new construction code. NYC BC 1968 still applies to many existing buildings. NYC BC 2014 retroactively applies for certain commercial.
NYC-specific:
California Title 24:
California-specific:
After being unique for many decades, Chicago harmonised in 2019. Still has Chicago-specific:
Considered most stringent state energy code in the US. Many requirements at IECC 2027 level applied today.
| Parameter | Value | Source |
|---|---|---|
| Floor-to-floor residential R-2 | 9-10 ft (2.74-3.05 m) | Industry practice |
| Floor-to-floor office | 12-14 ft (3.66-4.27 m) | Industry practice |
| Hotel ceiling clear (R-1) | 7.5 ft (2.29 m) min | IBC 1208.2 |
| Bedroom min ceiling | 7.0 ft (2.13 m) | IBC 1208.2 |
| Corridor width (>=50 occ) | 44 in (1118 mm) | IBC 1020.3 |
| Stair width (>=50 occ) | 44 in (1118 mm) | IBC 1011.2 |
| Riser height | 4 in min, 7 in max (R/A/B/E/I/M) | IBC 1011.5.2 |
| Tread depth | 11 in min | IBC 1011.5.2 |
| Travel distance B sprinklered | 300 ft (91.4 m) | IBC 1017.2 |
| Wall U-value (Zone 4 mass) | 0.42 W/m2K (R-13.0+R-3.8c.i.) | ASHRAE 90.1-2022 |
| Wind speed 0.4% (NYC) | 122 mph (54.6 m/s) | ASCE 7-22 |
| Wind speed 0.4% (Miami HVHZ) | 175 mph (78.2 m/s) | ASCE 7-22 |
| Wind speed 0.4% (Houston) | 124 mph (55.4 m/s) | ASCE 7-22 |
| Wind speed 0.4% (LA) | 96 mph (43 m/s) | ASCE 7-22 |
| Ground snow load (Boston) | 40-50 psf (1.9-2.4 kN/m2) | ASCE 7-22 |
Cross-references: load building-codes for IBC fundamentals (US is IBC's home jurisdiction); fire-life-safety for NFPA 101 + IFC; accessibility-design for ADA + ANSI A117.1 + Fair Housing; building-sustainability for LEED + ENERGY STAR + Passive House comparison; structural-systems for ASCE 7 / ACI / AISC depth; building-services for ASHRAE detail.
npx claudepluginhub amanbh997/skills-architectsProvides practitioner-grade building code expertise for architectural design, covering IBC occupancy classification, construction types, egress, fire protection, and international code comparisons.
Analyzes zoning regulations and generates form-based codes including Euclidean, performance, and transect-based systems. Useful for setbacks, height limits, FAR, use permissions, masterplans, and design-to-regulation translation.
Calculates maximum occupant loads per IBC Table 1004.5 for buildings/spaces, handling gross/net areas, use groups, jurisdictions (NYC/CA), with exportable reports.