Mechanicals · definition
Requirements ensuring fuel appliances get enough air in confined spaces (e.g., a furnace closet). Tightening the envelope can trigger this.
Source: NFPA — NFPA 54: National Fuel Gas Code
Where this term lands on a Columbus budget
The cost pages carry the current local ranges, and the guides explain what moves them. A published range becomes a project number only after someone looks at the site.