The Dos & Don’ts of Cedar Roof Restoration

According to the Cedar Shake & Shingle Bureau

Topical Treatment Products

It is not within the mandate of the Cedar Bureau to recommend brand names of topical roof treatment products. Consult with your local professionals for product information regarding cleaning and preserving cedar in your area. The Cedar Bureau does however, recommend the following:

Do use a topical treatment that:

  • Offers a MSDS (Material Safety Data Sheet) that lists the ingredients and the safety precautions.
  • Is labeled as a cedar roof treatment product or has a letter from the manufacturer stating that treating cedar roofs is an appropriate use for this product.
  • Is a water repellant, UV inhibitor, and/or EPA registered wood preservative
  • Has a manufacturer’s performance guarantee

Do NOT Use a topical treatment that:

  • Makes outrageous claims (such as a 10 year warranty)
  • Makes fire retardant claims
  • Is a sealant, waterproofer or plasticizer
  • Contains unfortified linseed oil, diesel fuel or crank case oil

The Cedar Bureau is aware of numerous bleaching and cleaning agents. Consumers are advised to heed the preceding topical treatment precautions before allowing such products to be applied to a cedar roof.


This is the most controversial issue in the care and maintenance industry. It is a fact that pressure washing by inexperienced people will cause significant damage to any material. Some debris can be easily removed with garden hose pressure.

Some contractors powerwash to clean roofs, while others do not. If powerwashing is used, the roof should receive a topical treatment to restore the roof.

The Cedar Bureau recommends having a professional assess each job on an individual basis to determine if powerwashing is appropriate or not. Care and maintenance professionals know the proper procedures, which include factoring in:

  • Age, condition and environment of roof Gallons sprayed per minute
  • Distance spray nozzle is held from roof Pressure per square inch and others…
  • Fan tip size

The Beauty of Cedar

Another good thing about cedar is that it is possible to replace and repair parts of the roof, without worrying that your replacement shakes or shingles are significantly different in composition from your original shakes or shingles. Over the hundreds of years that cedar has been used, the product has remained unchanged…it’s still cedar. As cedar advances to its mature stage, it is natural to expect some pieces to require replacement. Individual repairs are possible, and with prompt attention, proactive repairs can extend the life of your wise Certi-label cedar investment.

Copied verbatim from the New Roof Construction Manual issued by the Cedar Shake & Shingle Bureau January 2006

Contact address: #2-701 Horne Street Mission BC V2V 7A2
Telephone: 604-820-7700