Walk into any lumber yard in Athens or Atlanta to order fence boards, and you’ll encounter one of the industry’s most confusing conventions: nominal versus actual lumber dimensions. That “1×6” board you’re purchasing isn’t actually one inch thick or six inches wide. Understanding this sizing system saves Georgia homeowners from costly mistakes and helps ensure your fence project uses the right materials for lasting strength and beauty.
After 15+ years installing fences across Northeast Georgia, we’ve answered hundreds of questions about why fence boards don’t match their labeled dimensions. This guide explains industry sizing standards, how lumber shrinks during processing, and what these measurements mean for your fence’s durability in Georgia’s challenging climate.
Why Fence Boards Aren’t the Size They Claim
The lumber industry uses “nominal” measurements—historical reference sizes that don’t match actual finished dimensions. This practice dates back over a century when rough-cut lumber actually measured close to its stated size. Modern milling and drying processes reduce these dimensions, but the old naming system stuck.
Here’s what you’re really getting when you order common fence boards:
1×4 boards: Actually measure 3/4″ thick by 3-1/2″ wide 1×6 boards: Actually measure 3/4″ thick by 5-1/2″ wide
1×8 boards: Actually measure 3/4″ thick by 7-1/4″ wide 2×4 boards: Actually measure 1-1/2″ thick by 3-1/2″ wide
This isn’t deceptive labeling—it’s standard industry convention. Every lumber supplier in Georgia uses these measurements. Problems arise when homeowners calculate material needs based on nominal sizes instead of actual dimensions.
How the Lumber Drying Process Affects Dimensions
Fresh-cut lumber contains significant moisture. Raw wood from Georgia mills might contain 50-60% moisture content by weight. This “green” lumber must dry to 19% moisture or less for outdoor applications and 15% or less for indoor use.
As lumber dries in kilns or air-drying yards, it shrinks across the grain. A rough-cut 1-inch-thick board loses about 1/4 inch during drying. Width follows similar patterns. Length stays relatively stable since wood shrinks minimally along the grain.
Georgia’s red clay soil and high humidity add complications. Our region experiences humidity levels from 65% in winter to 85% in summer. Wood naturally absorbs and releases moisture with seasonal changes, causing dimensional movement throughout a fence’s life.
Quality mills plane dried lumber to consistent final dimensions. This surfacing process removes another thin layer, creating smooth, uniform boards ready for finishing. The resulting “dressed” lumber provides the actual dimensions listed above.
Impact on Fence Strength and Design
Actual board dimensions directly affect fence structural integrity. A privacy fence using 1×6 boards (actually 3/4″ thick) differs substantially from one using 5/4 boards (actually 1″ thick). That extra 1/4 inch thickness adds approximately 33% more material—significantly improving wind resistance and impact durability.
Consider these strength comparisons for wood privacy fencing in Georgia:
Standard 1×6 boards (3/4″ actual): Adequate for 6-foot fences in protected locations. May show deflection in strong winds.
Premium 5/4×6 boards (1″ actual): Better wind resistance. Recommended for exposed locations or 8-foot fences. Common in Oconee and Clarke counties where storms test fences regularly.
Heavy-duty 2×6 boards (1-1/2″ actual): Maximum strength for high-wind areas. Overkill for most residential applications but ideal for commercial properties or farm fences.
Board spacing calculations also depend on actual measurements. Planning a board-on-board fence with 1×6 boards? You’ll need to account for 5-1/2″ actual width, not 6 inches. This affects material quantities and final appearance.
What to Specify When Ordering Materials
Clear communication prevents measurement confusion. When discussing fence projects with suppliers or contractors, use both nominal and actual dimensions:
“I need 1×6 cedar boards—that’s 3/4 inch by 5-1/2 inches actual—for privacy fence pickets.”
Specify these additional details:
Grade: #1 or #2 for visible fence boards. #2 allows more knots but costs 20-30% less.
Species: Cedar, pine, or pressure-treated pine. Each behaves differently in Georgia humidity.
Moisture content: Request KD (kiln-dried) lumber at 15-19% moisture for outdoor applications.
Treatment level: For pressure-treated lumber, specify ground-contact (.40 retention) or above-ground (.25 retention) treatment.
For projects in Athens, GA and surrounding areas, we recommend ordering 10% extra material. Georgia’s red clay soil and humidity can damage boards during storage, and having backup pieces saves delays.
Don’t rely on “linear feet” measurements alone. A supplier quoting “500 linear feet of 1×6 fencing” might deliver boards of varying quality or treatment levels. Specify exact dimensions, grade, species, and treatment for consistent results.
Quality Indicators Beyond Thickness
Board thickness matters, but other factors determine fence longevity in Georgia’s climate:
Grain orientation: Vertical grain (edge grain) resists cupping and warping better than flat grain (face grain). Inspect boards for straight, tight grain lines running lengthwise.
Knot size and location: Small, tight knots cause minimal problems. Avoid boards with knots larger than 1 inch or loose knots that might fall out. Knots near board edges create weak points.
Moisture content: Use a moisture meter to verify lumber at 15-19% moisture. Wetter lumber will shrink after installation, causing gaps. Drier lumber might absorb moisture and swell.
Treatment penetration: For pressure-treated lumber, check for uniform greenish or brown color throughout. Inconsistent coloring indicates incomplete treatment—those areas will rot faster.
Straightness: Sight down each board’s length. Slight bows are acceptable and can be straightened during installation. Severe twisting or cupping indicates poor drying and will cause installation problems.
Quality varies significantly between suppliers. Athens-area lumber yards specializing in fencing materials typically stock better-graded boards than big-box stores. Professional contractors build relationships with suppliers who set aside premium boards for their projects.
Regional Sizing Variations and Standards
While nominal-to-actual conversions stay consistent nationwide, regional practices affect what sizes are commonly available. Georgia suppliers typically stock these fence board dimensions:
1×4 boards: Common for decorative picket fences and garden enclosures. Light duty.
1×6 boards: Standard for privacy fences. Most popular choice for residential projects from Lawrenceville to Marietta.
1×8 boards: Becoming more popular for modern horizontal fence designs. Covers more area per board, reducing installation time.
5/4×6 boards: Premium thickness for high-quality privacy fences. Increasingly requested in upscale neighborhoods.
Some Georgia mills offer custom dimensions. Need 7/8-inch-thick boards for a specific design? Custom milling costs 30-50% more but delivers exact specifications.
Southern lumber producers use different grading standards than Western mills. “Southern Yellow Pine #2” differs from “Western Red Cedar #2” in knot allowances and grain characteristics. Always verify grading standards when comparing suppliers.
Common Measurement Mistakes That Cost Money
Mistake #1: Calculating material needs using nominal dimensions. Planning a 100-foot fence using 1×6 boards? If you calculate based on 6-inch widths instead of actual 5-1/2-inch widths, you’ll come up 8-9% short on materials. That’s 9-10 extra boards for a 100-foot run.
Mistake #2: Ordering boards too thin for wind exposure. We’ve repaired dozens of fences where 3/4-inch boards couldn’t withstand Georgia wind gusts. Areas like Cumming and Gainesville with open terrain need thicker boards.
Mistake #3: Mixing nominal and actual measurements in designs. This creates spacing problems during installation. Contractors waste time recalculating on-site.
Mistake #4: Assuming all 1×6 boards measure exactly 5-1/2 inches. Mill tolerances allow 1/16-inch variation. Budget for slight spacing adjustments during installation.
Mistake #5: Failing to account for shrinkage after installation. Even kiln-dried lumber continues adjusting to local humidity. Expect 1-2% additional shrinkage during the first year in Georgia’s climate.
How Thickness Affects Different Fence Styles
Privacy fences: Standard 3/4-inch boards work for most applications. Upgrade to 1-inch boards for 8-foot heights or high-wind locations.
Board-on-board fences: Require precise thickness matching. Mixing 3/4-inch and 1-inch boards creates uneven shadows and amateur appearance.
Horizontal modern fences: Benefit from thicker boards. 5/4 or 2x materials minimize sagging between posts, which becomes visible with horizontal orientation.
Picket fences: Use 3/4-inch boards. Thinner materials look proportional for 3-4 foot fence heights.
Split-rail fences: Rails typically measure 2-1/2 to 3 inches thick (not following nominal standards). Posts measure 4-6 inches square. Check our split-rail fencing options for traditional farm-style designs.
Professional Installation vs. DIY Considerations
Professional contractors account for actual dimensions automatically. We calculate material quantities, spacing, and structural requirements using real measurements. Our experience with Georgia’s red clay soil and humidity patterns also guides material selection.
DIY fence builders often struggle with the nominal-versus-actual distinction. This leads to three common problems:
First, purchasing insufficient materials. Recalculating mid-project means additional supplier trips and potential mismatched lumber from different batches.
Second, incorrect post spacing. Posts placed for nominal board widths create gaps when actual boards are installed.
Third, structural weakness from using boards too thin for the application. This becomes apparent during the first severe weather event.
For complex projects or premium materials like cedar, professional installation provides better long-term value. Our team’s 15+ years installing fences throughout Northeast Georgia means we select appropriate materials and account for regional challenges.
Material Selection for Georgia’s Climate
Georgia’s humidity and temperature swings stress fence materials year-round. Summer humidity peaks at 85%, while winter occasionally drops to 50%. This 35% humidity variation causes wood to expand and contract repeatedly.
Cedar boards: Natural oils resist moisture and insect damage. The 3/4-inch actual thickness provides adequate strength for most residential applications. Premium choice but costs 40-60% more than treated pine.
Pressure-treated pine: Most economical option. Chemical treatment protects against rot and insects. Standard 3/4-inch boards work well. Expect some checking and minor warping as wood ages.
Cypress: Excellent rot resistance. Naturally stable in humidity. Limited availability in Georgia markets. Price comparable to cedar.
Board thickness matters more in Georgia than drier climates. Our humidity accelerates rot in areas where moisture accumulates. Thicker boards resist cupping and maintain structural integrity longer when moisture penetrates finish coatings.
Red clay soil retains moisture, keeping fence posts and lower boards constantly damp. This makes bottom board selection critical. Many contractors use treated 2x4s (1-1/2″ actual thickness) for kickboards instead of standard 1x6s. The extra thickness provides longer life where rot risk peaks.
Cost Implications of Different Thicknesses
Material costs scale with thickness and quality:
1×6 treated pine (#2 grade): $1.50-$2.50 per linear foot 1×6 treated pine (#1 grade): $2.00-$3.00 per linear foot
5/4×6 treated pine: $2.50-$3.50 per linear foot 1×6 cedar: $3.50-$5.00 per linear foot 5/4×6 cedar: $5.00-$7.00 per linear foot
For a typical 100-foot privacy fence using 60 boards:
Standard 1×6 treated pine: $150-$180 in materials Premium 5/4×6 treated pine: $150-$210 in materials
Standard 1×6 cedar: $210-$300 in materials Premium 5/4×6 cedar: $300-$420 in materials
These prices reflect Northeast Georgia market rates. Bulk purchases for large projects may qualify for 10-15% discounts. Transportation costs add $50-$100 for delivery outside metro areas.
Labor costs increase slightly with thicker boards due to additional weight and cutting time. However, this premium rarely exceeds 5-10% of total installation costs.
Maintenance and Long-Term Performance
Board thickness affects maintenance requirements. Thicker boards resist cupping and warping, reducing the need for repairs. They also hold finishes longer because there’s more material to absorb stain or paint.
Thin boards (3/4 inch actual) require refinishing every 2-3 years in Georgia’s climate. Thicker boards (1 inch or more) often last 3-5 years between treatments. This maintenance advantage adds up over a fence’s 15-20 year lifespan.
Check our fence maintenance tips for detailed care instructions that protect your investment.
Boards also resist impact damage better with increased thickness. A 3/4-inch board might crack when hit by a lawnmower or fallen limb. A 1-inch board typically survives the same impact with minor surface damage.
Making the Right Choice for Your Project
Select fence board thickness based on these factors:
Fence height: 6-foot fences work well with 3/4-inch boards. 8-foot fences need 1-inch minimum thickness.
Wind exposure: Protected yards use standard thickness. Properties with open fields or hilltop locations require premium 1-inch boards.
Budget: Standard thickness delivers good value for most applications. Invest in premium thickness for high-visibility areas or long-term installations.
Climate stress: Georgia’s humidity and red clay soil argue for thicker boards in ground-contact areas and lower sections prone to moisture.
Aesthetic preferences: Board-on-board and horizontal designs show thickness differences more than vertical privacy fences. Premium thickness looks better on showcase installations.
Need help selecting appropriate materials? Our team provides free consultations throughout Metro Atlanta and Northeast Georgia. We assess your property’s specific conditions and recommend materials that balance performance with budget.
Professional Installation Ensures Proper Material Use
Professional fence contractors eliminate confusion about board dimensions. We order materials using actual measurements, calculate quantities accurately, and select appropriate thickness for each application.
Our installation process accounts for Georgia’s unique challenges:
Red clay soil considerations: We set posts deeper and use proper drainage around posts to prevent rot acceleration.
Humidity adjustments: Board spacing accounts for seasonal expansion and contraction in Georgia’s humid climate.
Wind load calculations: Post spacing and board thickness match your property’s wind exposure for long-term stability.
Treatment specifications: We specify appropriate pressure-treatment levels for ground-contact areas versus above-ground sections.
Quality installation matters as much as material selection. Even premium 1-inch cedar boards fail if installed incorrectly. Our team’s 15+ years of Georgia fence installations means your materials perform as designed.
Ready to Build Your Fence Right?
Understanding nominal versus actual lumber dimensions helps you make informed decisions about fence materials. The difference between 3/4-inch and 1-inch boards might seem small, but it significantly impacts your fence’s durability, appearance, and maintenance requirements.
Georgia’s climate demands careful material selection. Our humid summers and red clay soil stress fence materials more than drier regions. Choosing appropriate board thickness for your specific location prevents premature failure and costly repairs.
Precision Fenceworks has installed thousands of fences throughout Northeast Georgia using materials selected for regional performance. We help homeowners navigate lumber specifications, select optimal board thickness, and install fences that withstand our challenging climate.
Get your free estimate or call us at (770) 725-0777 to discuss your fence project. Our experienced team will recommend materials matched to your property’s needs, ensuring your investment delivers lasting value and beauty.
Visit our fence styles gallery to see examples of different materials and thicknesses in completed projects throughout Athens, Atlanta, and surrounding areas. Each fence demonstrates how proper material selection and professional installation create structures that protect and enhance Georgia properties for years to come.
