Whether you're framing a house, building a deck, or tackling a DIY project, choosing the right materials is critical. Not all lumber and plywood are created equal—and understanding grades can save you time, money, and headaches on the job.

At Youngblood Builders Supply, we help customers every day find the right material for the job. Here’s a straightforward guide to help you do the same.

What Do Lumber Grades Mean?

Lumber grading is a system used to classify wood based on strength, appearance, and intended use. Grades are assigned by organizations like the National Lumber Grades Authority and American Lumber Standard Committee.

There are two main categories:

• Structural (Framing) Lumber
• Appearance (Finish) Lumber

Common Framing Lumber Grades

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1. Stud Grade

• Used for vertical framing (walls)
• Smaller knots allowed
• Not rated for heavy structural loads
• Cost-effective option for standard wall framing

2. No. 2 (Most Common)

• The industry standard for construction
• Good strength and moderate appearance
• Used for:
  • Floor joists
  • Wall studs
  • Roof rafters

If you’re building anything structural, this is usually your go-to.

3. No. 1 Grade

• Fewer knots and stronger than No. 2
• Used where higher strength is required
• Common in load-bearing applications

4. Select Structural

• Highest strength rating
• Minimal defects
• Used in:
  • Heavy load applications
  • Engineered builds

Pressure-Treated Lumber Grades

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Pressure-treated lumber is graded by exposure level, not just appearance:

• Above Ground – Deck rails, fence pickets
• Ground Contact – Posts, framing near soil
• Severe Duty – Permanent ground or water contact

Using the wrong treatment level can lead to early failure—this is one place you don’t want to cut corners.

Hardwood & Appearance Lumber Grades

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For visible projects like cabinets or furniture:

• FAS (First and Select) – Highest quality, minimal defects
• Select – Slightly more imperfections
• No. 1 Common – Good for cabinets and painted projects
• No. 2 Common – Utility use

The higher the grade, the cleaner and more consistent the look.

Understanding Plywood Grades

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Plywood grading is based on the quality of the face and back veneers.

Letter Grades (Face Quality)

• A Grade
  • Smooth, sanded
  • Paint-ready
  • No knots
• B Grade
  • Minor repairs allowed
  • Still smooth
• C Grade
  • Knots and visible defects
  • Not sanded
• D Grade
  • Rough, large knots
  • Lowest quality

Common Combinations

• AC Plywood
  • One smooth side, one rough
  • Great for cabinets or visible surfaces
• BC Plywood
  • Good balance of quality and cost
• CDX Plywood
  • Most common for construction
  • Used for:
    • Roof decking
    • Wall sheathing
    • Subfloors

The “X” in CDX means it’s rated for exterior exposure (glue, not waterproof forever).

Specialty Plywood Options

• Marine Grade
  • No voids, waterproof glue
  • Used in high-moisture environments
• Pressure-Treated Plywood
  • Resistant to rot and insects
• Fire-Rated Plywood
  • Meets building code for certain applications

Choosing the Right Material

Here’s a quick cheat sheet:

• Framing a house? → No. 2 lumber + CDX plywood
• Building a deck? → Pressure-treated (ground contact where needed)
• Cabinets or furniture? → Select/FAS lumber + AC plywood
• Outdoor structure? → Treated lumber + exterior-rated plywood

Why It Matters

Using the wrong grade can lead to:

• Structural issues
• Warping and twisting
• Premature rot or failure
• Higher long-term costs

Choosing the right grade upfront keeps your project solid and professional.

Shop Quality Materials at Youngblood Builders Supply

At Youngblood Builders Supply, we stock a full range of:

• Framing lumber
• Pressure-treated lumber
• Hardwood boards
• Construction and cabinet-grade plywood

We can also special order exactly what you need if it’s not in stock.

Visit us in-store or shop online at
youngbloodbuilderssupply.com

Need Help? Ask the Pros

Not sure what grade you need? Our team is here to help you get it right the first time.

Stop by or contact us today—we’ll make sure your project starts with the right materials.