How to Dry Crawlspaces

Drying crawlspaces can be difficult and time-consuming due to the low ceiling clearance and dirt/gravel flooring.

Effective August 3, 2015, OSHA has implemented a new rule (ASTM D5755) designed to protect workers in confined spaces. This is partially in response to two fatalities. Two workers died while applying primer to floor joists in a crawlspace. They were burned when an incandescent work lamp ignited vapors from the primer. In another incident, a flash fire killed a worker who was spraying foam insulation in an enclosed attic. The fire was caused by poor ventilation.

Under the new rule, permits to access specific confined spaces are granted by the general contractor or lead contractor on each job. There are numerous safe entry procedures requiring careful planning and preparation by the contractor ahead of time.

The rule will apply to any space that meets the following three criteria:

1. Is large enough for a worker to enter it
2. Has limited means of entry or exit
3. Is not designed for continuous occupancy

A space may also be a permit-required confined space if it has a hazardous atmosphere, the potential for suffocation, a layout that might trap a worker through converging walls or a sloped floor, or any other serious safety or health hazard.

Employers will be required to train workers to ensure they know about the existence, location, and dangers posed by each permit-required confined space and maintain related records for possible inspection by OSHA or other interested parties in the case of an accident or complaint investigation.

Directions:

1. Remove all debris in the crawlspace.
2. Remove any standing water.
3. Dry all structural materials and the floor in crawlspace. Due to the low clearance and materials present that can hold a lot of moisture, it is generally recommended to use either a heat-based or desiccant system and ducting.
4. Use your meters to monitor the job project daily.
5. Apply Microban Disinfectant Spray Plus to all structural surfaces.
6. Clean any contaminated surfaces by spraying Fiberlock Advanced Peroxide Cleaner on all structural surfaces.
7. Re-dry surfaces if needed.
8. If moisture or humidity in the crawlspace has been or might be a recurring problem, apply a Mold Preventative Coating to all structural surfaces, such as walls and ceilings.
9. Install a vapor barrier.
10. Install a crawlspace dehumidifier if needed for long-term moisture control.