InstaBidsFor homeowners
Composite deck cost vs wood: which fits your home?
It depends on which part of the deck: Wood suits the substructure under the deck boards. The right choice depends on whether you are choosing the deck boards or the frame under them, how often you will refinish wood boards, and how much water reaches board ends and edges.
| Factor | Composite (wood-plastic) | Wood |
|---|---|---|
| Up-front cost, in the Forest Products Laboratory's words (no price figure) | USDA Forest Products Laboratory (2002): "Although WPC decking is more expensive than pressure-treated wood, manufacturers promote its lower maintenance, lack of cracking or splintering, and high durability." (WPC: wood-plastic composite) | no official figure |
| The substructure under the deck boards | USDA Forest Products Laboratory (2002): "WPCs are used for deck boards but not the substructure." | USDA Forest Products Laboratory (2013): lumber used in decks is "usually pressure treated with a preservative, or the lumber used is a naturally durable wood such as redwood or western redcedar." |
| Where one maker's composite boards are evaluated for use (ICC Evaluation Service report) | ICC Evaluation Service report (2025) on one maker's composite deck boards: they "are limited to exterior use as deck boards for balconies, porches, and decks." | no official figure |
| Water at board ends and edges | One USDA Forest Products Laboratory field study of capped and uncapped boards (2015, called preliminary by its authors): "Significant moisture was detected in the analyzed WPCs regardless of capping. Moisture was concentrated near the board ends and edges of capped WPCs." | USDA Forest Products Laboratory (2013), on treated decking: "it is still advisable to treat the ends cut during construction with a WRP." (WRP: water-repellent preservative) |
| Decay fungi and mildew | The same 2015 study: "Capped material is susceptible to fungal attack and weight loss particularly at exposed ends or areas of attachment." | USDA Forest Products Laboratory (2013): "Without proper maintenance, wood decks can develop problems such as checks and cracks, raised grain, and mildew" |
| Keeping mold and mildew down | The same 2015 study, on capped boards: "These products were designed to give increased performance against mold that commonly occurred and resulted in staining of uncapped WPCs." | USDA Forest Products Laboratory (2013): "Applying an additional finish to wood decks will minimize the problems of cracking, raised grain, and mildew growth." |
| How often a clear deck finish is renewed | no official figure | USDA Forest Service estimate (2013): "The service life of a WRP finish is about 1 year on the exposed surfaces of wood decks" (the finish, not the deck) |
| Which finish to use | no official figure | USDA Forest Products Laboratory (2013): "penetrating finishes, not film-forming finishes, should be used on wood decks." |
| Why wood decks are taken out of service | no official figure | USDA Forest Products Laboratory (2013): "Most decks are retired because of cracks and checks that mostly could have been avoided by timely finishing." |
| Color over time | USDA Forest Products Laboratory (2002): "Most WPCs tend to lighten over time" | USDA Forest Products Laboratory (2013): "The bright color of the wood on weathered decks can be restored by application of commercial products (called deck cleaners, brighteners, or restorers)." |
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| Priority | Choose |
|---|---|
| the frame under the deck boards (the substructure; USDA Forest Products Laboratory, 2002) | Wood |
What does deck building cost?
For prices, see How much does a deck cost?
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Sources for the facts on this page
- USDA Forest Service, Forest Products Laboratory, Wood-plastic composites in the United States (Forest Products Journal, June 2002), government, read 22 October 2026.
- ICC Evaluation Service, ESR-3771 composite deck boards (reissued November 2025), standards body, read 22 October 2026, subject to renewal November 2026.
- USDA Forest Service, Forest Products Laboratory, Durability of capped wood plastic composites (American Wood Protection Association proceedings, 2015), government, read 22 October 2026.
- USDA Forest Service, Forest Products Laboratory, Finishes for Wood Decks (revised July 2013), government, read 22 October 2026.