How We Protect Decks and Foundations with Waterproofing Solutions

Waterproofing Expertise from a Trusted General Contractor

We’re a general contracting firm that’s been serving clients since 1997. Over the years, we’ve taken on a wide variety of construction projects, but more recently, we’ve found ourselves specializing in waterproofing—particularly deck waterproofing. We work with homeowners, houseboat owners, and fellow general contractors to waterproof decks and other problem areas such as large planters, foundations, and spots where water intrusion is difficult to diagnose. With over 50 years of experience in construction, I’ve developed a keen eye for spotting structural issues and identifying potential sources of leaks. This expertise allows us to solve tricky waterproofing problems that others may overlook.

Waterproofing Decks Over Living Spaces

Most of the waterproofing work we do is on decks built over living space. These projects require careful product selection based on the structure, finish surface, and project requirements. Sometimes a specific waterproofing product is outlined in the blueprints or requested by the contractor. However, in many cases, homeowners rely on our professional judgment to choose the best product for their needs. After all, by law, we must stand behind the integrity of our waterproofing work for a minimum of 10 years. Decks come with a variety of finish surfaces—floating wooden decks, tile, pedestal tile systems, lightweight concrete, and even standard concrete in the case of carports. Each of these requires a waterproofing solution that is flexible, UV-stable, and capable of withstanding expansion and contraction.

Walking Deck Systems

Most of the decks we waterproof fall into a category known as “walking decks.” This simply means the final waterproof coating is also the surface you walk on. These are typically urethane-based systems, although occasionally an epoxy coating may be requested. After the flashing, crickets, and drains are installed, urethane waterproofing involves applying at least four separate coats, with each coat applied only after the previous one has fully cured. The final topcoat—also called the color coat—adds not only the final color but also a tougher finish. The base and sand coats beneath it are more flexible and provide better elongation, helping the deck move without cracking. After the final coat is applied, we recommend waiting at least three days before placing furniture on it.

Recoating Existing Decks

We also provide recoat services for existing urethane decks. This process usually involves grinding the old surface, making any necessary repairs—ranging from minor to extensive—and applying a fresh epoxy primer, a sand coat, and a final color coat. As a general contractor, we’re also equipped to handle related work such as removing doors to access pan areas, repairing parapet walls, and restoring or replacing damaged railings.

Products We Recommend

When working with pedestal tile systems, floating wood decks, or decks under concrete, we often recommend two standout products: Gaco LM 60 and Neptune Coatings WetSuit. Gaco LM 60 is a high-performance, two-part polyurethane system that only requires a single coat. Part A is mixed with Part B before application. Neptune Coatings WetSuit is a fluid-applied neoprene waterproofing product. It’s non-toxic, zero-VOC, water-cleanable, and Class A fire-rated. It also boasts impressive elongation—up to 2,000%. Both systems require proper flashing before application, and both need a protection board placed on top after curing. This board—typically a 4'x8' sheet of asphalt about 1/8" thick—helps shield the waterproofing membrane from damage. Once installed, the deck can support sawhorses, toolboxes, and other equipment.