Lumber Grades… What are they for? Does your lumber pass or fail?
The lumber grade of treated wood is something you’ll want to consider when planning your next outdoor building project. Lumber grades are assigned at the sawmill where the logs are cut. The lumber is primarily graded on the strength of the board. For the most part, lumber is available in three tiers of quality: Good, Better, and Best.
The Canopy Building crew cuts stringers from treated lumber to construct new stairs for a deck in Hoover, Alabama.
Good–Number 1 and Number 2 grades are commonly sold at local lumberyards. They have good strength ratings but also come with imperfections such as large knots, rounded bark edges, and some bowing or twisting. Number 1 will have fewer imperfections than Number 2. These grades are ideal for a cost-conscious DIY homeowner.
Better–You’ve hit Prime time. The Prime grade of Number 1 and Number 2 lumber features the same strength properties, but are listed as Prime based on appearance (regarding the amount of bark on the edges or the number of knots). This lumber is a bit more expensive, but you get what you pay for.
Best–To guarantee the most beauty for your back yard, choose either C & Better or Select Structural grade products. With these two grades you get the strongest lumber properties and better appearance. Knots will be small, few and far-between, and there should be no bark on the edges.
These best grades are also available in kiln-dried options, which eliminate the waiting period typically required before painting or staining for “wet” lumber. The KDAT (kiln-dried after treatment) lumber is a high-grade wood product selected for its appearance, providing similar appeal to wood-composite boards while maintaining a genuinely natural look. Typically backed by a lifetime warranty, KDAT lumber offers a number of benefits. Not only is it ready to be painted, stained or sealed immediately, but the kiln-drying process reduces the lumber’s natural tendency to shrink, cup and warp, and it weighs less than freshly treated lumber. KDAT products are easier to handle, cut and install, have greater strength, more stiffness, and increased holding power.
Learn more about treated lumber and KDAT building products from our friends at yellawood.com .
Jeff Winkle of Highland Properties, Inc. installs KDAT posts on an extensive house remodel in Birmingham, Alabama.
— Matt Weber