Of all the things one might consider in short supply here in Seattle, rain wouldn’t likely make anyone’s list. We’ve had those ninety day stretches with rain every day. We have seasonal affective disorder sufferers. We have the highest sunglasses purchases in the nation because no one can remember where they put their sunglasses the last time they used them nine months ago. But all those things lead to a greater appreciation for the outdoors and a love of decks! But with decks and rain comes that perpetually wet mossy space under them, unless they are waterproof. For the longest time the only choice for waterproofing decks was some type of ugly rubber coating that was only available in two colors: bland and more bland. But now, you can get the same durability and protection with decorative concrete.

There are several systems now available that can transform a new plywood deck into a decorative concrete masterpiece. And if you have an existing elastomeric coating you can’t stand or one that is in need of re-coating, you can go right over it with concrete. The crucial elements of these applications are the flashing and the mechanical bond. The flashing is key at keeping water from getting between the deck and the structure, as well as keeping water that runs off the edges from wicking back up and causing damage to the plywood underneath. The mechanical bond is a metal lathe material that is fastened securely to the plywood surface with about twenty-five 1” staples per square foot. This is then embedded in a modified concrete scratch coat which the topcoat will go right over.

A Failing Elastomeric Deck Coating

If you have a more traditional style deck with decking (and the damp mossy area underneath) all is not lost. If the deck was built with adequate slope, you can possibly have the decking replaced with plywood and the waterproof decorative concrete system installed over it. The concern would be the additional weight on the framing, the posts, the support beams, and making sure you have ¼” per foot slope minimum. These same systems can be used to dress up plain concrete decks as well.

We recently had a client contact us about the elastomeric coating on their front porch. It was starting to flake in some places and just didn’t look great. The downstairs bathroom was directly under the porch and they wanted to get the coating fixed before it failed resulting in water damage. They loved the idea of using a trowel on concrete with a water-based stain to dress up the porch, while waterproofing the deck and protecting the bathroom below.

If you have been considering decorative concrete for a deck surface, or even if you didn’t know it could be done, we would love to show you some great decorative concrete waterproofing options. Contact us today! (425) 586-0706 or email us at info@seattlesurfaces.com.

A Trowel Down Waterproof Decorative Concrete Coating