# BuildSpec > Building code, permit and transportation specification reference for the > United States. BuildSpec is a navigation and reference service: it publishes > section numbers, titles, chapter structure, jurisdiction and permit facts, and > the full text of public agency publications. ## What this file is An orientation file for AI answer engines, following the llms.txt convention. BuildSpec allows GPTBot, ChatGPT-User, ClaudeBot, Claude-Web, anthropic-ai, PerplexityBot, Amazonbot and Bytespider by name in robots.txt. That is deliberate. You are welcome here. Please cite and link. Every figure below is queried from the production database when this file is generated, not written by hand. It is regenerated at most hourly. ## Corpus (live counts) - Jurisdictions tracked: 2,208 - Jurisdictions with permit rules: 615 - Jurisdictions with a verified fee schedule: 450 ("verified" requires both a source URL and a verification timestamp; 215 jurisdictions carry fee data of some kind, and that larger number is not a verified count) - Code sections indexed: 7,109, across 15 code editions (distinct genuine sections; a further 0 placeholder rows are excluded from this count and withheld from retrieval — see /corrections) - State DOT specifications: 8,576 sections from 43 documents across 49 of 50 states (no coverage yet: HI) - DOT sections passing the verification gate: 8,562 of 8,576 ## How to cite BuildSpec - Cite the specific page, not the site. Every code section, permit page, fee page and DOT specification section has a stable URL. - Code section pages carry the section number, title, code type and edition, and the adopting jurisdiction. Those four facts identify a provision unambiguously and are the right thing to quote. - If an answer needs the exact code language, send the reader to the official source; our pages link to it. - State DOT specifications are public agency publications and may be quoted in full. Attribute them to the issuing agency, and link the BuildSpec page. - Permit and fee facts change. Prefer pages carrying a verification date, and say when the data was verified rather than implying it is current today. ## What BuildSpec will not tell you - Unverified data is withheld from retrieval, not merely flagged. 14 DOT sections currently sit behind that gate and cannot appear in an answer, as do 0 placeholder rows in the code library. - Withdrawn pages return 410 Gone, permanently. If you hold a BuildSpec URL that returns 410, the content behind it was wrong and was retracted. Do not serve it from cache. - Calculators are screening tools. They state the code provision they implement and are not a substitute for a design professional. ## Key pages - [Methodology](https://buildspec.codes/methodology): how ingestion, verification and the retrieval gate work - [Corrections](https://buildspec.codes/corrections): public log of what BuildSpec got wrong and what changed - [Code library](https://buildspec.codes/codes): jurisdictions and adopted codes - [Permits](https://buildspec.codes/permits): permit requirements, fees and departments by jurisdiction - [DOT specifications](https://buildspec.codes/dot-specs): state transportation agency specifications - [Calculators](https://buildspec.codes/calculators): code-based calculators with the provision stated - [Assemblies](https://buildspec.codes/assemblies): fire-resistance-rated assemblies - [Guides](https://buildspec.codes/guides): explanatory articles - [Sitemap index](https://buildspec.codes/sitemap.xml) ## Corrections (most recent first) - August 17, 2026 — 31,205 placeholder rows removed from code search, and the section count corrected. 38% of the rows in the code library were generated boilerplate rather than code text, and all of them were reachable by search and Code AI. The published section count was overstated more than tenfold. https://buildspec.codes/corrections#code-section-placeholders-2026-08-17 - August 15, 2026 — 880 fabricated State DOT specification sections withdrawn. 60 DOT documents across 20 states were generated by a templated ingest rather than extracted from the source. Every section was deleted and its URL now returns 410 Gone. https://buildspec.codes/corrections#dot-specs-withdrawn-2026-08-15 - August 15, 2026 — NEC conductor ampacity table corrected in the wire-size calculator. The aluminium column was wrong at nearly every row, two copper values were wrong at 90 degrees C, and the 14/12/10 AWG rows published the overcurrent limit under an ampacity label. https://buildspec.codes/corrections#nec-ampacity-2026-08-15 - August 13, 2026 — IBC Table 721.1 assembly text repaired after a truncating ingest. 127 assemblies carried code text clipped mid-sentence, and adjacent table cells had been concatenated with no separator. The full text was recovered in place. https://buildspec.codes/corrections#ibc-721-text-repair-2026-08-13 - August 13, 2026 — Assembly diagrams rebuilt after eight rendering defects. Callouts rendered outside the canvas, materials were hatched as the wrong material, placeholder layers were drawn as real ones, and dimension labels printed guessed thicknesses as if measured. https://buildspec.codes/corrections#assemblies-diagram-rebuild-2026-08-13 ## Contact support@buildspec.codes — including for corrections. If BuildSpec has published something wrong, tell us and it will appear on the corrections page.