What Is Pressure Treated Lumber
Pressure treated lumber is wood that has been infused with preservative chemicals to resist moisture, rot, and insect damage. This treatment process extends the lifespan of the material, making it ideal for outdoor applications such as decks, fences, and structural framing exposed to the elements.
For deck construction, pressure treated lumber is commonly used for framing, posts, joists, beams, and sometimes decking boards.
Common Sizes for Deck Construction
Pressure treated lumber for decks is commonly available in:
2x4
2x6
2x8
2x10
4x4 posts
6x6 posts
These sizes are typically used for joists, beams, ledger boards, and vertical supports. Selecting the correct size depends on span requirements and local building codes.
Ground Contact vs Above Ground Treated Lumber
Not all treated lumber is rated the same.
Above Ground Treated Lumber
Used for deck boards and framing components that are elevated and exposed to airflow.
Ground Contact Treated Lumber
Designed for posts or framing that may touch soil or retain moisture. Ground contact lumber contains a higher level of preservative for increased durability.
Choosing the proper rating ensures compliance with building standards and long-term performance.
How Long Does Pressure Treated Lumber Last
When properly installed and maintained, pressure treated lumber can last 15 to 30 years depending on exposure conditions and maintenance.
Lifespan is influenced by:
Climate conditions
Drainage and ventilation
Fastener quality
Regular sealing or staining
Proper spacing and airflow underneath decks significantly extend structural life.
What Impacts Deck Lumber Pricing
The cost of pressure treated lumber for decks depends on:
Board size and thickness
Treatment level
Lumber market fluctuations
Freight and regional availability
Quantity purchased
Larger framing packages often reduce overall per-unit cost. Checking availability locally ensures accurate pricing based on current inventory.
Pressure Treated Lumber vs Composite Decking
While composite decking is popular for surface boards, most decks still rely on pressure treated lumber for framing. Treated wood remains the standard structural base due to strength and cost efficiency.
Many homeowners combine pressure treated framing with composite deck boards for durability and aesthetics.
Finding Treated Lumber for Decks Near You
If you are building or repairing a deck in Boise or the Treasure Valley, selecting the correct grade and treatment level is essential.
Capital Lumber supplies pressure treated lumber, dimensional lumber, and structural materials for deck construction and outdoor projects. Contact the team to confirm sizing, availability, and job site delivery options.
