Viking Roof Preservation is a company that Cleans, repairs and Chemically Preserves Cedar Shake, Asphalt, and Flat Roofs. We will come out to your home and provide you with an in-depth inspection. Once we have determined the condition of your roof and what is needed to repair your roof. We will give you an estimate for work. We use only Complete Cedar Shield for preserving our customer's roofs. We have tried all of the other products available in Chicago and have found it to be the very best. Complete Cedar Shield is the only product that addresses' all of the issues a cedar shake roof is exposed to. Every wood roof has some amount of mold, algae or moss. Sometimes algae only show itself when the roof is wet.