Roof Cleaning

Some highly reflective roofs aren't so reflective after a few years. To maintain the energy savings of a white roof, you have to make sure it stays white. A good cleaning may be in order here.

The ceramic granules on damp, shaded asphalt shingles are a welcoming environment for moss and lichen. These growths can damage the shingles and significantly shorten the life of the roof.

More Pictures:

1. Cleaning a TPO Roof Membrane

2. Lichen Growing on Asphalt Shingles

Useful Links:

1. GeneralSimple roof cleaning guidelines for low-slope single-ply roof membranes are provided by the Chemical Fabrics and Film Association - Vinyl Roofing Division.

2. GeneralZinc and its use in preventing moss and lichen from growing on roofs: information provided by Oregon State University's College of Science.

3. General: Energy Costs: If you are wondering about the energy savings that might result from cleaning the dirty white roof on your building, you have to read this paper, "Saving Energy by Cleaning Reflective Thermoplastic Low-Slope Roofs". Made available by the Oak Ridge National Laboratory's Building Technologies Research and Integration Center.

4. Copper Roofs: "Removing Black Stains from Exterior Copper". Available on the website of the US General Services Administration

5. Shingles - Asphalt: "Algae & Moss Prevention and Cleaning for Asphalt Roofing Systems" provides basic information. Available at the ARMA website.

6. Shingles - Asphalt: "Algae Discoloration on Roofs" provides basic information. This short technical bulletin is available on the Canadian Asphalt Shingle Manufacturers' Association website.

7. Shingles - Wood: "Care and Maintenance of Wood Shingle and Shake Roofs" explains things pretty well. Available on Oregon State University's Pacific Northwest Plant Disease Management Handbook site.