As house painting contractors in the Chicago area, we clean and stain cedar, using a variety of products, from pigmented-transparent stains, semi-transparent stains and solid-color stain. We recently refinished a 22-foot high canopy, adorned with large cedar beams and tongue- and-groove cedar planks. In this particular case, the wood had never been sealed, or finished in any way. Consequently, mildew had grown over the surfaces, especially around the lights illuminating the canopy.
First, in order to safely reach the canopy surfaces, we had to install two layers of scaffolding, as well as use two large articulated ladders. We then had to clean the wood and kill the mildew spores. After experimenting with several cleaning methods, we settled on rags as the best tool to use to clean and rinse the surfaces. We ruled out using power washing, for fear that injecting water between the tongue-and-groove planks might swell up the boards and cause unwanted problems.
To execute the wood finishing, we applied a coat of pigmented varnish to give rich wood tones to the cedar. We then applied a final coat of clear varnish over all the surfaces to give them the appearance of a furniture finish. In all, the project took about seventy hours to complete. Our clients will likely never have to refinish their canopy again. All that may be required is a cleaning every sis to ten years.