How to Get Rid of the Odor and Smell of a Polyurethaned Wood Floor

Ventilate polyurethane to disperse out-gassing compounds.

Solvents used in architectural coatings such as polyurethane varnish, a strong coating used on floors, helps resins and alkyd solids bond to wood floors. As they evaporate, they leave the solids to dry and harden. The gasses given off are volatile organic compounds, or VOCs, and the evaporation process is called off-gassing. VOCs are organic, so they break down easily in the atmosphere. Concentrated in a closed space, however, they cannot combine with air and retain their harmful forms. Continued exposure contributes toxins to indoor pollution that can damage respiratory, nervous and digestive systems.

Things You'll Need

• Whole house fan or air mover
• Baffles for window
• Duct tape
• Replacement furnace and air filter media

Instructions

1. Open a window in the room and install a whole house fan. Close the sash as tightly as possible and use cardboard or scrap lumber to block parts of the window frame that might allow air around the edges of the fan mounting back into the room.

2. 

   Open windows on the opposite side of the house pull air in.

   Open windows a few inches to halfway on the opposite side of the house, depending on the weather, and turn the fan on. A constant flow over the floor and out of the room will establish a negative pressure so the gases rising from the floor can’t circulate inside the house.

3. 

   Be prepared to replace appliance filters.

   Turn off humidifiers and air filters. Humidifiers slow off-gassing and air filter media may conserve some VOCs and release them later. Purchase replacement furnace filters and change them after off-gassing. If your air cleaner is attached to your furnace and runs automatically, purchase new media to change the filter after off-gassing is completed.

4. Keep the room warm, around 80 degrees Fahrenheit, to encourage evaporation. This way, the fan can pull out the most gas.

5. Run the fan night and day to establish a negative pressure and keep the windows open to provide a supply of fresh air. After a week or two, depending on the size of the area, give the floor the sniff test. If you can still smell urethane vapors, run the system for another week.

Tips & Warnings

• Work smart; provide good ventilation while you work with polyurethane and allow each coat to dry completely before re-coating.

• Most floors will need one to two weeks of negative pressure, but some urethane requires up to a month of off-gassing.

• A whole house fan is a worthy investment. Mount it in the attic when its off-gassing duties finish. It will help keep the house ventilated during hot summers and in winter when the house is sealed up tight.

• If you have an attic fan, turn it off or reverse it to bring air in so it doesn’t alter the negative pressure in the room where the window fan is pulling air over the floor.

• Never use a fireplace during off-gassing; the negative pressure may cause a chimney backdraft.

• Avoid all open flames -- solvent off-gasses are flammable.

• Urethane coverings with petroleum-based solvents, including heavy naphthenic, a proven carcinogen produce the longest-lasting VOCs. They may be labeled as oil-based or marine spar varnish. In addition to ventilating the work area using negative pressure, a family with small children may want to stay with family or check into a motel while the work is being done.

References

• Woodfloorsonline: Types of Wood Floor Finishes
• Minnesota Department of Health: Volatile Organic Compounds in Your Home
• California Air Resources Board: Reducing Indoor Air Pollution
• California Air Resources Board: Ventilation and Indoor Air Quality in New Homes
• U.S. Department of Health and Human Services: Household Products Database

Resources

• National Association of Home Builders: National Green Building Standard