ProWood® Ground Contact pressure-treated lumber (UC4A) is our most versatile and commonly used treatment level. Whether it touches soil, sits on the ground, or endures frequent moisture exposure, Ground Contact lumber is designed to resist rot, fungal decay, and termite damage where it matters most, at the foundation of your project.

With a higher chemical retention level than Above Ground treatments, Ground Contact is suitable for both structural and non-structural uses, especially where moisture or soil exposure is constant or likely.

Backed by the ProWood Lifetime Limited Warranty, it’s the trusted choice for long-term durability and peace of mind.

Where to Use Ground Contact Lumber

Ground Contact is ideal for applications that:

• Touch the ground or are partially buried in soil
• Are exposed to frequent or long-term moisture
• Are critical to structural integrity
• Are difficult to maintain, repair, or replace after installation

Common Use Cases

Ground Contact treated wood is commonly used for:

• Deck framing (joists, beams, posts) in contact with the ground
• Stair stringers and ledger boards
• Retaining walls
• Fences and fence posts
• Raised garden beds and landscape edging
• Mailbox and sign posts
• Pergola and gazebo footings
• Walkways or paths where wood sits directly on soil or gravel

Benefits of Ground Contact Treated Lumber

• Higher treatment level for superior protection in ground contact conditions
• Extended service life in outdoor environments
• Protection against rot, fungal decay, and insect damage
• Versatile applications
• Meets AWPA standards
• Available in a variety of dimensions and profiles
• Backed by the ProWood® Lifetime Limited Warranty

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