Question:

I’ve had a severe fire loss in my home with lots of water used to put it out. The contractor specified by the insurance company didn’t do a lot of deodorizing, and now I’m getting odor coming out of the woodwork. What should have been done? I’ve heard that thermal fogging might remove the odor. What should I do now?

Answer:

Smoke odor removal from burned structures with water damage is a multiphase process that must begin within hours or days after the loss, and continue from tear-out to dry-in and finishing. There are two types of odor with which you are dealing: smoke odor and biological (fungi, bacteria) odor. The fire caused the smoke odor, while the biological issue is caused by the water used in extinguishing the fire, coupled with time. If anything, the water likely exacerbated the fire contamination and odor.
Having said that, procedures to consider include, but aren’t necessarily limited to, the following:

1. Remove all structural components that are charred or which seal smoke or moisture within pockets of saturation. In extensive losses, blown or bat insulation must also be removed and replaced. It’s a mistake to be too conservative here.
2. Remove floor coverings after they collect the fallout of ceiling and wall demolition.
3. Once removed, structural framing and subfloor materials must be carefully evaluated for damage (charring, warping, etc.). Remove and plan to replace as required.
4. Salvageable wall framing should be treated with appropriate odor counteractants, which, in some cases, may include an appropriate biocide, depending on the extent of microbial contamination.
5. As close to the outset of restoration procedures as possible the HVAC (air conditioning system) must be either removed or thoroughly restored. This is particularly critical to prevent smoke particles, which range from 0.1 - 4 microns, from being released into breathable air. Ciliated surfaces on bronchial passages are able to filter particles only as small as 10 microns, so this is an important step as they have the potential to penetrate deeply into lung tissues where, at best, they cause irritation, and at worst, they could result in scarring of the alveoli.
6. Framing materials must be allowed to dry to within 4 percent of normal moisture content, which generally is around 10% in Texas.
7. While the home is unoccupied, and as successive areas are dried in, the use of a combination of ozone deodorization and wet or dry fogging to oxidize or otherwise neutralize odor is highly recommended. Both processes must be applied by trained professionals to avoid health risks or the potential for damage from the process itself.
8. Framing materials should be sealed with an appropriate sealer, before replacing drywall, paneling, decking, etc., or odor will leach out of structural materials for months, if not years to come. Simply putting up new drywall and taping and mudding joints will not seal in untreated odor.
9. As individual rooms are completely reconstructed, deodorization efforts should continue, progressing from least damaged areas back to the source. Usually, source areas are that last to be dried in and reconstructed.
10. Salvageable drywall, if any, should be sealed carefully and painted (two good coats of quality paint).
11. Airing out the structure both during reconstruction and for several days after each phase of construction helps minimize VOCs that off-gas from new materials, adhesives, and coatings.
12. All salvable furnishings, contents, and removable fixtures should be processed meticulously in a restoration facility before being returned to the fully-restored home.