Deck Preservation Test: Poly Coatings over CPES™ Photo A: This is a three-year-old entrance deck outside a home in the Seattle area. It is constructed of 1 X 6″ fir planks on 2 X 8″ joists. The deck had been been untreated and exposed to the weather. Photos B and C: These two pictures show what can happen to raw, untreated wood. Fastening nails will pop and cracks develop in some of the planks. These breaks in the wood allow water to penetrate into the wood and to the plank/joist seam. Here it can be trapped, resulting in moist wood and, with summer heat, the real possibility of wood rot developing. To prevent this from happening we wanted to protect the deck and provide a real-world demonstration of our wood preservatives and coatings. PRODUCTS USED IN THIS TEST: • CPES™   as a protective primer. • RHINO TOP:   a water-based acrylic/epoxy exterior coating. • ELASTUFF 120:   a 2-part, 100% solids, polyurethane coating. • UNIFLEX 255 Aliphatic   a 2-part, elastomeric high-tensile finish, final coating. Clear deck coatings and stains do not offer very good protection against rot and UV light deterioration. In addition, the coatings have to be renewed at frequent intervals for good appearance. For these reasons we favor the use of opaque coatings for decks, specifically the new epoxy/acrylic “super-paint” (RHINO TOP), and our new waterproof polyurethane coatings (ELASTUFF 120 and UNIFLEX 255 Aliphatic). Photo D: With an initial CPES (Clear Penetrating Epoxy Sealer) prime for wood protection/hardening and final coat bonding, we coated the deck with various combinations of our products. We will post images annually to show deck appearance and wear patterns. Photo E: Here is the deck after coating, indicating the type of coating used over the CPES prime coat. Photo F: This is a picture of the board splits after coating with two coats of ELASTUFF 120 and two coats of RHINO TOP. The cracks filled and the ELASTUFF 120 expanded out into protruding ridges as it cured . The ridges could have been shaved off but there was no particular reason to do so. Photo G: The railings were also CPES primed, and then coated with one application of UNIFLEX 255 Aliphatic. Note: The exposure to weather warped some of the deck planks to the point where they could not be nailed flat again. Since they were not in the walkway area, we choose not to replace them. Click the following text links for more information on CPES™ or on the Polyurethane Top Coatings.

	The Rot Doctor, Inc. P.O. Box 30612 • Seattle, WA 98113 Voice: 206.364.2155  •  Fax: 206.364.4744 E-mail: drrot@rotdoctor.com	Order by phone, fax, mail, or e-mail. © 1997-2009 The Rot Doctor, Inc.
Most products ship same day from both coasts! Our business hours are 6 AM to 5:30 PM Pacific Time, Monday-Friday. Tech support is available over weekends.