Remediation
Removing moldy materials: what goes and how to take it out
In plain English
What happens to a moldy material depends on how porous it is. R520's rule of thumb: porous materials with actual growth, such as drywall, insulation and ceiling tile, are removed and thrown away. Semi-porous materials such as wood studs can usually stay and be cleaned by HEPA vacuuming and wiping, or by sanding or wire-brushing when growth has gone into the surface. Small spots of surface growth on non-porous materials, with nothing hidden behind, usually need only HEPA vacuuming and damp wiping.
The method of removal matters as much as the decision to remove. Dry, moldy materials release spores easily, so R520 calls for cutting rather than tearing, unscrewing or gently prying drywall off studs, and setting saw depth so the blade does not go through the backing. Hammers, crowbars and saws without dust collection are discouraged. Carpet can be covered in plastic before it is pulled. Debris goes straight into 6-mil bags, and anything carried through clean areas is double-bagged.
R520 does not put the job of finding and fixing the water source on the remediator. It does say someone qualified must do it and that responsibility should be clear from the start. New materials should not go in until the area passes evaluation or verification. Contaminated, non-regulated debris can generally go to ordinary landfills, subject to local rules.
Key points
- Porous materials with growth are removed; semi-porous wood is usually cleaned.
- Cut, unscrew or pry gently; avoid smashing and dry tearing.
- Bag debris right away in 6-mil plastic; double-bag through clean areas.
- Do not rebuild until clearance is passed.
- Decide at the outset who is responsible for fixing the water source.
Official text
This topic is covered in our own words because the standard behind it is copyrighted; we cite it below rather than reproduce it.
Citations
- IICRC S520 Reference Guide, IICRC S520 Standard and Reference Guide for Professional Mold Remediation — Reference Guide — Ch. 11, pp. 118–123. Best practice