It is common knowledge among tradies that water is the enemy of timber and the leading cause of deterioration for decks. It can lead to mould, mildew, rot and premature deck failure. To prevent moisture from undermining your next installation, keep these four tips in mind…
1. Survey the slope
Water must drain away from a deck structure. Set the deck framing at a pitch of 1% to 2% to slope away from the building site. If you plan to install an under-deck drainage system, decide where the water will discharge. Consider adding a French drain (a.k.a. an engineered trench), reservoir or other means to redirect the water or collect it for use in watering a garden or planting area.
2. Protect the substructure
The timber used in deck building is pressure-treated to be water-resistant – not waterproof. To protect a deck’s structural elements from moisture and rot, it’s critical to apply flashing tape, such as Trex® Protect, over all the joinery and blocking. Designed specifically for decking applications, and available in sizes for use on joists, bearers and rims, these self-adhesive butyl tapes also seal deck fasteners and help screws to hold longer and stronger by preventing moisture penetration and defending against splitting that can result from seasonal freezing and thawing.
3. Use low-maintenance decking
Timber decks can be beautiful but any type of wood, whether pressure-treated lumber, cedar or exotic hardwood, must be cleaned regularly and coated every few years to keep it looking good and prevent water damage. That’s why composite and PVC boards, which are practically impervious to water, continue to gain popularity. They require little upkeep and last for decades.
4. Divert water with a deck drainage system
For more comprehensive waterproofing of your substructure, consider adding a deck drainage system. Designed for use on elevated decks, these systems capture and divert water away from a deck. This not only protects the foundation from moisture penetration but also keeps the space beneath the deck dry and usable for storage or as an additional outdoor living area. Offering maximum protection, the Trex® RainEscape® system installs above the joists of a deck to shield the entire foundation. It also allows homeowners to discreetly run gas and electrical lines beneath the drainage system and a soffit ceiling to power lights, ceiling fans, appliances and electronic components.
For more waterproofing tips, visit TrexProtect.com.