For AI agents: read the machine-readable documentation index at /llms.txt or the single-file full reference at /llms-full.txt.
Form a Business

Grade.

Municipal Code of Chicago § 18-28-512.3
in effect
Sign in to generate a plain English summaryAsk Belisarius Agent
18-28-512.3 Grade. Exhaust system ducts shall not be trapped and shall have a minimum slope of one-eighth unit vertical in 12 units horizontal (1-percent slope).
Source: City of Chicago, Municipal Code of Chicago (American Legal Publishing, codelibrary.amlegal.com)URL: https://codelibrary.amlegal.com/codes/chicago/latest/chicago_il/0-0-0-2687525Fetched: 10/24/2026

Starting a business in Illinois? Illinois LLC guide: costs and requirements