Decking wood falls into three buckets: preservative-treated softwood, naturally durable hardwood, and modified wood.
Choosing from the types of wood for decking comes down to one trade: how much upkeep you’ll accept versus how long the boards should last. The three practical US choices are pressure-treated pine, naturally durable species like cedar and ipe, and modified woods such as Accoya. The Timber Decking and Cladding Association recommends timber capable of a minimum 15-year service life, which means either naturally durable hardwood or pressure-treated softwood approved for its end use.
Pressure-Treated Softwood: The Workhorse
Pressure-treated pine dominates US decks because it balances cost with decades of service. The University of Tennessee Institute of Agriculture lists preservative-treated wood as one of the three main deck-board categories and notes that untreated pine is not recommended. The treatment forces preservative deep into the wood fibers, protecting against rot and insects.
There’s a catch worth knowing before you build. The TDCA says that from January 2020, deck joists or other exterior structural support timbers requiring preservative pressure treatment should be treated to Use Class 4, whether or not they sit in ground contact. Deck boards themselves face a less strict requirement, but supports carry a higher bar. Ask your lumberyard to confirm the treatment class before you buy framing material.
Naturally Durable Hardwood: Cedar, Ipe, and Teak
Softwoods come from evergreen conifers; hardwoods come from broadleaved trees, and the terms have nothing to do with literal hardness. Species like Western red cedar, redwood, ipe, and teak resist decay naturally without chemical treatment.
Timber Development UK lists cedar, redwood, ipe, and pine among common deck woods and breaks them down by type. Softwood decking species include quality redwood (pine), whitewood (spruce), Douglas fir, Western red cedar, and larch. Hardwood options include Balau/Yellow Balau, Cumaru, Ipe, Iroko, and Massaranduba.
- Cedar and redwood: naturally resistant softwoods that age to silver-gray; lighter weight makes them easy to work with.
- Ipe and cumaru: premium hardwoods that resist rot and insects; dense enough to dull standard blades.
- Teak and iroko: oily hardwoods with strong natural durability; teak carries a higher price tag.
The trade-off is simple. Natural woods cost more upfront than treated pine, and the dense hardwoods can be tough on tools, but they skip the chemical treatment entirely. If you’re weighing the full cost picture before committing, our best deck wood roundup covers top-rated choices in detail.
Modified Wood: The Engineered Upgrade
Modified wood starts as fast-growing softwood and gets transformed through heat or chemical processes to mimic the durability of naturally resistant species. Timber Development UK lists Thermowood, Kebony, and Accoya as modified decking options, positioned as longer-lasting than standard softwood.
Heat-treated Thermowood gets its stability from high-temperature processing. Accoya is acetylated pine, and the process alters the wood’s cell structure so fungi can’t feed on it. Accoya’s own guidance positions it as a durable, low-maintenance decking option with a long service life.
Modified woods typically cost more than treated pine but less than premium hardwoods like ipe, and they offer a stable, uniform appearance with strong dimensional stability.
Choosing Between Deck Wood Types
The right choice depends on your budget, your tolerance for maintenance, and your local climate. Consumer-facing guides consistently identify cedar, redwood, and pressure-treated wood as the three common wood-decking choices in the US market, and each has a clear home.
| Material | Durability | Best For |
|---|---|---|
| Pressure-treated pine | 15+ years with proper treatment class | Budget builds and large decks |
| Cedar / redwood | Naturally resistant, moderate life | Visual appeal with easy workability |
| Ipe / cumaru / teak | Very durable, decades of service | Premium decks where longevity wins |
| Accoya / Thermowood | Long-lasting, stable, low-maintenance | Modern builds wanting uniform look |
Untreated, non-durable pine is not recommended for deck building under any circumstances. If you’re comparing wood against composite options, Timber Development UK notes that composite decking may be heavier than standard softwood and may require closer support spacing during installation.
For most US homeowners, pressure-treated pine delivers the best value, with cedar as the upgrade pick for natural character and ipe for those who want a board that will outlast the house. Timber Development UK’s decking timber guidance confirms the standard species categories and their service-life expectations.
FAQs
Is pressure-treated wood the cheapest decking option?
Yes, pressure-treated pine is generally the most affordable wood decking choice in the US market. The preservative treatment extends its life well beyond untreated lumber, and it remains the default for budget-conscious builders who want a deck that lasts.
How long does cedar decking last compared to ipe?
Cedar typically lasts 15 to 20 years with proper maintenance, while ipe can serve 40 years or more thanks to its natural density and decay resistance. The trade-off is cost: ipe runs significantly higher per square foot and requires harder fasteners and drilling.
Can I use untreated pine for a deck?
No, untreated pine is not recommended for deck construction. The University of Tennessee Institute of Agriculture explicitly advises against it, and it will rot quickly when exposed to moisture and ground contact. Always specify treated lumber or naturally durable species for exterior projects.
References & Sources
- Timber Decking and Cladding Association. “Decking Timber Options.” Details durability classifications and pressure-treatment requirements including Use Class 4 guidance.
- University of Tennessee Institute of Agriculture. “Wood Decks: Material Selection.” Covers preservative-treated wood categories and the recommendation against untreated pine.