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Thomson Roof Treatment moss removal, roof cleaning and roof maintenance. Our entire family and staff are committed to meeting the high standards of moss removal and roof maintenance our customers demand. Therefore, we have exceeded client expectations in Victoria BC for over 35 years! As a result, a large percentage of our business for decades has been from repeat customers.

TRT's referrals are mainly from Insurance Companies, Roofing Contractors and Home Inspectors because Thomson Roof Treatment exemplifies the method of regular roof maintenance RCABC recommends.

We deliver you the best service for moss removal in Greater Victoria, Saanich, Esquimalt, View Royal, Sidney, Colwood, Langford, Sooke and the Capital Regional District.

Click for the BBB Business Review of this Roof Cleaning & Stain Removal in Victoria BC

Our Mission

Our mission is to provide quality roof care that preserves the life of your roof and improves the look of your home.

Manual Removal

We remove moss by hand that has accumulated and is damaging the roof structure by trapping moisture in the seams of roof shingles and flashing. Doug and his team clean away the loose debris from the roof, clear out your gutters and always tidy up the grounds before they leave your site. Your roof will immediately have more curb appeal!


We gently apply Thomson Roof Treatment! It's a unique non-toxic solution and is safe for pets and your garden. Our treatment saturates the roof shingles and neutralizes any moss, lichen, mold or mildew present. That means all the microscopic spores and root systems are killed immediately and continue to wash away for the coming months of rain. Most importantly, we use a gentle, saturating method of application; we do not use pressure washing, which can damage your roof.


After Thomson Roof Treatment has removed the moss, lichen and mildew from your roof and cleared the gutters so they flow properly- you receive a guarantee! TRT's warranty means that your roof will remain moss, lichen and mildew free for up to 2-years or we will return to make sure that you are satisfied, at no cost to yourself. Doug and his crew assess each roof individually and always provide you with a guarantee in writing.

Get in touch today for a free quote!

Cedar Hill Links 10 out of 10

December 9, 2019

As we are a commercial account,your firm demossed 12 of our townhomes. I was impressed with the professionalism of your onsite staff and also impressed with the modern equipment that your firm uses. This is the first time I have had to use your company service and strongly recommend this company to any other strata’s.

Lisa M. 10 out of 10

December 5, 2019

Left everything very tidy

Peter H. 9 out of 10

December 2, 2019

Client didn’t leave any feedback

Maureen W. 10 out of 10

November 30, 2019

Excellent service.

Phil R. 10 out of 10

November 26, 2019

Great job. Professional and thorough

Bob G. 10 out of 10

November 25, 2019

Client didn’t leave any feedback

Glenn S. 10 out of 10

November 25, 2019

Excellence, professionalism, executed perfectly and with a pleasant sense of humor. Absolutely perfect 10! Thanks

John C. 10 out of 10

November 23, 2019

Our roof looks fantastic and we really appreciated the outstanding service (thank you for doing the garden shed, and especially for the great clean-up… the yard looks better than before!). Excellent… happy to recommend.

Lori M. 10 out of 10

November 23, 2019

Easy to deal with. Great results.

Jan G. 10 out of 10

November 23, 2019

The quote was done quickly, it was clear and easy to understand. The work was well done & cleaned up completely. Thank you