Researchers at UC Riverside say roofs coated with Titanium Dioxide can reduce smog forming pollutants. Engineering students sprayed ordinary clay tiles with titanium dioxide and it removed 88% – 97% of the nitrogen oxide pollution from the air.
Ozone, the main ingredient in smog is created when nitrogen oxides react to sunlight. Nitrogen Oxides are gases that are created by vehicle exhaust, power plants and industrial stacks.
An estimated 21 tons of nitrogen oxides could be removed from the air each day if 1 million roofs were sprayed with titanium dioxide.
Kawaii Tam, a lecturer in UC Riverside Department of Chemical and Environmental Engineering, said “Even a light coating of titanium dioxide can be effective. It would take only about $5 worth of the compound to treat existing roof tiles of an average sized home”.
Titanium Dioxide products on the market now
While there are commercial tiles on the market available now, Tam said they can be expensive and few studies have determined their effectiveness. Most, if not all light colored or white wall and roof paints have titanium dioxide in them to make them opaque and reflective.
White reflective paint is also being used on flat roofing materials to reduce the heat island effect by lowering the roof’s temperature up to 80 degrees. The Lawrence Berkeley Laboratory in California estimates a minimum of 25% savings in energy use for the average homeowner with a roof with a reflective white coating.
Roofing materials tend to lose their reflective properties over time so it is suggested that you provide regular maintenance and remove dust and debris and occasional reapplications from your local roofer.
