Guide
Kitchen remodels and hood relocations: cleaning before and after construction
A remodel that moves the hood, extends the duct, or swaps the cooking line is not the same as a routine clean. Construction dust and weld spatter land in the same places grease does. Skipping the before-and-after cleaning sequence leaves you with a new-looking canopy over a dirty duct — and often a fire-marshal reinspection that fails for inaccessible sections or missing access doors.
Before demo: what to do with the old system
| Situation | Cleaning move | Why |
|---|---|---|
| Reusing duct, fan, or hood sections | Full-system clean to bare metal before demo starts | Grease on reused metal becomes a fire load inside the “new” system; photos prove the baseline |
| Scrapping the entire exhaust path | Still clean or bag heavily soiled sections before cutting | Keeps grease off the job site and out of the construction waste stream; roof and curb stay cleaner |
| Hood stays, only appliances move | Inspect for grease depth; clean if dirty; re-check suppression coverage for the new appliance layout | UL 300 / NFPA 96 triggers when cooking equipment is relocated or cooking media change — suppression is a separate contractor |
| Temporary kitchen during remodel | Treat the temporary hood as its own system with its own interval and reports | Temporary does not mean uninspected |
Owner responsibility for cleanliness stays with the owner unless transferred in writing (NFPA 96 §4.1.5 secondary). Put the remodel GC, mechanical contractor, and cleaning company on one scope sheet so nobody assumes the other party cleaned the duct.
During construction: lock these before the ceiling closes
- Shop drawings to the AHJ: hood listing, duct route, rooftop termination, clearances, and access openings — same pattern fire marshals use on new commercial cooking plan reviews
- Access panels: cleanouts on horizontal runs and at turns; enclosure access doors lined up with every cleanout where the duct is wrapped or in a shaft. See missing access panels and fire wrap
- Hinged upblast fan + hold-open: so the fan can tilt for cleaning after opening. See fan hinge checklist
- Grease drain and receptacle: fan drain into a ≤1 gal visible receptacle; rooftop containment that does not block the hinge. See grease cup inspection points
- Duct leak test and hood performance test before concealment and final approval (same construction gates as a new restaurant). See opening a new restaurant
- Suppression redesign/acceptance: nozzle layout must match the new appliances; acceptance test before CO
After construction: the post-build clean
A brand-new or newly relocated exhaust path is not clean. Construction leaves sheet-metal shavings, weld spatter, drywall dust, and sealant residue in the hood, duct, and fan. Secondary operator guidance treats the post-construction bare-metal clean as the step that removes that debris and produces the first label and written report for the remodeled system.
- Schedule the clean after mechanical and suppression finals, before the first day of cooking
- Require a full-system scope (hood, filters, plenum, ducts, fan, grease receptacle) with inaccessible areas listed in writing — not a canopy wipe
- Keep the report and photos in the on-site binder with the duct test and suppression acceptance papers. See documentation binder
- If the cooking type changed (for example fryers to charbroiler), the inspection interval follows the new type. See menu or equipment changes
When the inspection clock restarts
| Cooking type (IFC Table 606.3.3.1 / NFPA Table 12.4 pattern) | First inspection after reopen |
|---|---|
| Solid fuel | 1 month from first day of cooking |
| High-volume (24-hour, charbroiling, wok) | 3 months |
| All other / moderate | 6 months |
| Low-volume | 12 months |
Counting from the first day of cooking after the remodel is the same working rule we use for new kitchens; your AHJ can set its own start date. A remodel that only refreshes finishes without touching the exhaust does not automatically reset the clock — keep the existing interval unless the AHJ says otherwise.
Who it’s for / not for
- For: owners and GMs doing a kitchen remodel, hood relocation, or line swap; franchise remodel teams; landlords reviewing tenant build-outs
- Not for: routine scheduled cleaning with no construction; taking over an existing kitchen without moving the hood (that is a records review — see buying or taking over); design/permit engineering questions (those belong to your engineer and AHJ)
Sources
- NAFED: NFPA 96 2024 vs 2021 edition comparison (§4.1.5 owner responsibility; §4.7 AHJ notification of alteration/replacement/relocation; §10.2.3 UL 300 triggers on equipment relocation)
- 2024 IMC Chapter 5 (UpCodes) (duct leak test §506.3.2.5; cleanouts §506.3.8–9; enclosure access §506.3.12; fan hinge §506.5.4; hood performance §507.1.7)
- 2024 IFC Chapter 6 (UpCodes) (Table 606.3.3.1 inspection frequency; cleaning and tags)
- Facilitec Southwest: Opening a new restaurant — NFPA 96 from day one (secondary: post-construction bare-metal clean before cooking; construction debris in duct/fan)
- City of Fairburn (GA) Fire Marshal: Commercial cooking / NFPA 96 hood plan review checklist (PDF) (shop drawings, roof plan, access — representative AHJ remodel/new-hood packet)
Next step
Before demo, write one page: what stays, what goes, who cleans what, and the AHJ contact for alteration notice. Book the post-construction full-system clean on the same calendar as the mechanical final.