A fire job isn't finished when the char is gone. The callback that costs a restorer their reputation almost never comes from a scorched wall - it comes from the smell that creeps back three weeks later, once the insurer has signed off and the homeowner has moved back in. In 2025, the industry finally got a formal answer to "how much cleaning is enough": the first ANSI-approved IICRC standard dedicated entirely to fire and smoke damage restoration, ANSI/IICRC S700. For contractors, it's less a new set of rules than a codification of what separates a thorough restoration from a rushed one.
A Documented Standard of Care
Before S700, fire restoration leaned heavily on the general principles in S500 (water damage) and a lot of accumulated trade knowledge. S700 changes that by setting out, in detail, how to assess the presence and intensity of fire residues and odour across a structure, its systems and its contents - and by requiring that the assessment produce a written Restoration Work Plan (RWP) before cleaning begins. That plan needs to define the extent of the fire-affected area, the residue types present, the cleaning and odour-control methods selected for each surface, and how success will be verified at the end.
Practically, this raises the bar on documentation. A verbal walkthrough and a general clean is no longer a defensible standard of care - insurers and adjusters are increasingly familiar with S700 and will expect a scoped plan to match it.
Match the Cleaning Method to the Residue, Not the Room
Combustion doesn't leave one type of residue - it leaves several, and treating them the same is the single most common mistake on fire jobs. Fast, hot fires (paper, wood, most structural fires) leave dry smoke residue: light, powdery, and best lifted with dry chemical sponges before any wet cleaning touches the surface. Slow, low-heat, oxygen-starved fires - smouldering couches, electrical fires, anything involving plastics or rubber - leave wet smoke residue: sticky, prone to smearing, and heavily odorous, which needs solvent or emulsifying cleaners rather than a dry sponge.
Kitchen and cooking-related fires add protein residue, which is often invisible but intensely odorous, requiring degreasing agents and thorough deodorisation rather than surface wiping. Furnace puffbacks and fuel-based fires leave oily, petroleum-based residues that need their own solvent chemistry. Running one generic cleaning pass across all of it either fails to lift the residue or smears it deeper into porous surfaces - and either way, the odour comes back.
Odour Is a Source Problem, Not a Masking Problem
Under S700, deodorising isn't a final spray-and-go step - it's tied directly to source removal. Combustion byproducts settle into carpet fibres, wall cavities, insulation and HVAC ductwork, and no amount of fragrance will out-compete an unaddressed source. The sequence that holds up is: remove or seal unsalvageable porous materials, clean and deodorise the residues that can be treated, then manage the airborne particulate and VOCs generated during the work itself.
This is where equipment selection matters. Running HEPA air scrubbers during dry sponging and demolition keeps fine soot particulate from redistributing through the structure while technicians work, rather than letting it settle on surfaces that have already been cleaned. Thermal fogging or other vapour-phase treatments can then reach the same air pathways smoke used to penetrate wall cavities and contents - but they work on cleaned surfaces, not as a substitute for cleaning them.
Don't Skip the HVAC and Cavities
Smoke travels through return air and wall cavities long before anyone notices the smell. S700 explicitly calls out building systems, not just visible surfaces, as part of the assessment. Ducting, insulation, and wall and floor cavities near the fire origin should be inspected and, where contaminated, cleaned or isolated as part of the scope - otherwise the HVAC system just keeps redistributing residue after the visible restoration is complete. Establishing negative air pressure and adequate ventilation during demolition and cleaning, using axial fans or similar air-moving equipment to keep contaminated air directed away from clean zones, is standard containment practice worth building into every scope.
The Practical Takeaway
S700 doesn't ask restorers to do anything fundamentally new - it asks them to do what good technicians already knew, consistently and on paper. Assess before you clean, match the method to the residue type, treat odour as a source-removal problem backed by proper air filtration, and don't stop at the surfaces you can see. That's the difference between a job that holds up and one that comes back.
