How to DIY A Deck Drainage System


(NewsUSA) - If you plan to add an elevated deck to your home, there’s one element that will greatly increase its value and function: an under-deck drainage system. These systems, which divert water to keep the space beneath a deck dry, are easy to install for both professional builders and DIYers, and virtually doubles an outdoor living space.


















Why Install a Drainage System?

An under-deck drainage system creates dry space below the surface of a deck that can be used as a patio, outdoor kitchen, private spa area, bonus storage and more. These systems also protect the wooden joinery of the substructure from moisture that can lead to decay, adding years onto the life of a deck.

Choosing the Right System.

There are two main types of deck drainage systems – those that install above the joists before the deck boards are laid and those that are retrofitted beneath the joists of an existing deck. The latter systems leave deck joists exposed to the elements while an above-the-joist system, like Trex® RainEscape®, protects the entirety of a deck’s foundation from moisture penetration. It also allows homeowners to discreetly run gas and electrical lines between the drainage system and a soffit ceiling to power lights, ceiling fans, appliances and electronic components.

Installing as Simple as 1-2-3.

A deck drainage system uses a network of troughs and funnels that can be installed using tools you likely already have on hand at home. A pair of scissors or a utility knife, a staple gun, and a caulk gun are typically all that’s needed.

Installation can be done in three simple steps:  

  1. Position the downspouts and troughs. Cut the funnels to match the joist spacing and position them along a rim joist and/or leger board. Lay the trough material, ensuring proper placement to guide water into the downspouts. Be careful not to seam or overlap the troughs.
  2. Staple all components into place. Repeat the installation of funnels and troughs across all joists.
  3. Tape all joists and seams. Use butyl tape to seal all seams and any spots where screws may penetrate the system. This creates a watertight installation.

Finishing Touches

With a drainage system in place, you can finish your under-deck space with furniture, lighting, accessories and anything else you might want to create your dream outdoor oasis.

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