Backyard Builders Announces Guidance on Decking Materials and Regional Moisture

LYMAN, SC – September 02, 2026 – PRESSADVANTAGE –

Decking materials respond differently to sustained moisture, and federal research places the southeastern United States in the highest hazard zone in the continental country for decay of wood exposed above ground. Backyard Builders Decks and Outdoor Living has outlined how those regional conditions factor into material selection for new deck projects.

The USDA Forest Products Laboratory publishes climate index values for estimating decay hazard to wood exposed outdoors above ground, calculated from National Climatic Data Center records for locations across the country. Values below 35 indicate little decay risk, values between 35 and 70 indicate moderate risk, and values above 70 indicate high risk. Regions that combine high rainfall with a mild climate carry the greatest hazard, a description that covers both the Southeast and the Pacific Northwest.

Those conditions apply year round rather than seasonally. Warm temperatures and frequent precipitation together create the environment in which decay develops, which means the exposure a deck faces is a function of regional climate rather than of any single wet stretch. Material selection accounts for that sustained condition.

Wood, composite and PVC decking respond to moisture in different ways. Pressure-treated wood absorbs and releases water as humidity and precipitation change through the year, and the boards expand and contract accordingly. Cedar and redwood contain natural oils that resist moisture absorption more effectively than untreated lumber, though prolonged wet exposure still affects them. Denser hardwood species including ipe, tigerwood and cumaru limit moisture penetration through grain structure, and manufacturers of those products publish maintenance schedules distinct from those written for softwoods.

Composite and PVC boards absorb less water than solid wood because of their manufactured composition, and manufacturers publish product-specific gapping and installation requirements that account for the difference. Actual performance varies by formulation, species, installation method and manufacturer specification, which is why material guidance is established per product rather than per category.

“Two decks built with the same boards can perform very differently depending on what the site does with water,” said Jason White, owner of Backyard Builders Decks and Outdoor Living. “Shade, airflow underneath and which way the yard drains change the exposure, so material selection has to start with the site rather than with a sample.”

Site conditions shape that exposure directly. Properties with limited airflow beneath the deck, heavy tree canopy or northern orientation retain moisture longer than open, south-facing sites. A structure built close to grade holds humidity differently than an elevated one with open space beneath it. Those differences influence board spacing, ventilation and grading alongside the choice of material itself.

Framing materials respond to moisture at different rates as well. Wood, steel, aluminum and composite framing each behave differently under sustained exposure, and framing selection is made to suit both the decking material above it and the drainage conditions of the property. Because framing is concealed once decking is installed, decisions made at that stage are not readily revisited later.

Structural fasteners and connectors sit within the same exposure. Hardware selection is specified alongside framing material rather than treated as a separate consideration, since connection points carry load and remain in contact with treated lumber over the service life of the structure.

Deck design and consultation is the stage at which those variables are assessed. A property assessment establishes how the site handles water, what the orientation and canopy conditions are, and how the intended structure will sit relative to grade. Three-dimensional models and two-dimensional plans are produced before material is ordered, so that the specification reflects site conditions rather than being adjusted during construction.

Maintenance requirements follow from the material selected. Wood decks are cleaned, sealed and stained on a recurring cycle to manage moisture absorption, and the interval depends on exposure as much as on age. Exotic hardwoods follow separate schedules from softwoods and pressure-treated lumber. Composite and PVC surfaces have their own cleaning requirements published by their manufacturers.

Periodic inspection applies across all materials. Early moisture-related wear appears on the surface before it reaches framing and connections, and identifying it at that stage keeps the work within the scope of cleaning, sealing or board replacement rather than structural repair. Existing decks that have gone several seasons without inspection are the ones where surface wear and structural wear are most easily confused.

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For more information about Backyard Builders Decks and Outdoor Living, contact the company here:

Backyard Builders Decks and Outdoor Living
Jason white
+18647401274
jason@backyardbuildersdeck.com
200 Newman Dr, Lyman, SC 29365, United States

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