Most pressure-treated wood decks today last around 10–15 years depending on the quality of the installation, maintenance, sun exposure, moisture, and overall weather conditions. With regular staining, sealing, and upkeep, some pressure-treated decks can last longer, but modern PT lumber typically does not perform the same way older pressure-treated wood did decades ago.
Much of today’s lumber is grown and milled faster than older-growth wood, which can lead to more shrinking, twisting, cracking, and movement as the wood dries over time. Newer pressure-treated lumber also tends to hold more moisture when first installed, which is why homeowners may notice boards warping or checking during the first few seasons.
While pressure-treated wood is still a common and cost-effective option for deck construction, many homeowners now choose composite decking, PVC decking, or alternative framing systems for longer-lasting, lower-maintenance outdoor living spaces designed to hold up better over time.