· by Michael Blair, Nashville's Deck
Composite decking is sold as maintenance free and wood as a constant chore. Neither is quite true. What separates them here is heat underfoot, refinishing, and how each handles our humidity.
What each needs
Wood needs cleaning and resealing or restaining, realistically every two to three years in Middle Tennessee sun. It can be sanded and refinished, so a tired deck becomes a good one.
Composite needs washing, and that is largely it. It cannot be refinished — surface damage, deep scratches and fading are permanent.
Heat is the local factor
Dark composite gets genuinely hot in a Nashville August, hot enough to be uncomfortable barefoot. Lighter colors and capped products with reflective pigments are much better.
Wood runs cooler. On a fully exposed south or west deck that difference is worth weighing seriously.
- Wood: cheaper, refinishable, cooler, needs sealing every two to three years
- Composite: costlier, no refinishing, can get very hot in dark colors
- Capped composite resists staining and fading far better than uncapped
- Either way the frame underneath is ordinary treated lumber
Mold and the shaded deck
In Middle Tennessee humidity, any deck that stays shaded and damp grows mold and algae. Composite is not immune — organic film on the surface supports growth regardless of what is underneath.
Airflow beneath the deck matters more than the material. A deck close to grade with blocked ventilation stays damp and grows things whatever it is made of.
Cost over the life
Composite costs substantially more installed. Over twenty years, counting periodic staining of wood, the total costs converge without composite clearly winning.
The real difference is what you spend your time on. If you will not stain a deck every couple of years, wood degrades and composite does not, and that is the decision.