Free Professional Tool

Shiplap Calculator Pro (USA)

Calculate exactly how many shiplap boards you need for your wall project. Trusted by 50,000+ American homeowners and contractors in 2025.

4.9/5 Rating Verified Accurate SSL Secure USA Standards
Wall Measurements
12%
Openings to Subtract
Your Shiplap Estimate
How Shiplap Boards Fit Together
Stud 16″ OC 16″ OC 16″ OC Board 1 Board 2 0.5″ Overlap Board 3 5″ Coverage Width (1×6 board = 5.5″ actual – 0.5″ overlap) Nail into stud Shadow Line

Cross-section view showing how shiplap boards overlap with a 0.5-inch rabbet joint, nailed into wall studs at 16 inches on center.

USA Shiplap Board Sizes Reference

Shiplap boards are sold by their nominal size, but the actual dimensions differ. The coverage width accounts for the standard 0.5-inch overlap (rabbet). Use this chart to select the right board for your project.

1×4
Actual: 0.75″ x 3.5″
Covers: 3″ per row
1×6
Actual: 0.75″ x 5.5″
Covers: 5″ per row
1×8
Actual: 0.75″ x 7.25″
Covers: 6.75″ per row
1×10
Actual: 0.75″ x 9.25″
Covers: 8.75″ per row

How to Calculate Shiplap for Your Wall (Step-by-Step)

Follow this proven method used by professional contractors across the United States to estimate shiplap materials accurately.

1

Measure Wall Width and Height

Use a tape measure to find the total width and height of each wall in feet. Measure at the widest and tallest points. For gable walls, measure the triangular section separately.

2

Subtract Openings

Measure all doors, windows, and other openings you won’t cover with shiplap. Subtract each opening’s width x height from your total wall area. The calculator does this automatically.

3

Select Your Board Size

Choose your shiplap profile. The most popular choice for interior accent walls is 1×6 (covers 5 inches per row). For exterior siding, 1×8 is more common for faster installation.

4

Calculate Board Coverage

Each board covers: (Coverage Width in inches x Board Length in inches) / 144 = square feet per board. For a 1×6 x 8ft board: (5 x 96) / 144 = 3.33 sq ft per board.

5

Divide and Add Waste

Divide your total wall area by the coverage per board to get the base count. Then add 10-15% waste for cuts, mistakes, and defects. Always round up to full boards.

6

Estimate Fasteners and Supplies

Plan for one 2-inch finish nail per stud per row. For a 12-foot wall with 8-foot ceiling and 16-inch stud spacing, that’s approximately 10 studs x 19 rows = 190 nails. Add construction adhesive for superior hold.

Shiplap Cost Guide (USA 2025 Average Prices)

Current market prices for shiplap materials and installation across the United States. Prices vary by region, wood species, and supplier.

Material TypeCost Per Board (8ft)Cost Per Sq FtBest For
Pine (Primed)$6 – $10$1.80 – $3.00Interior walls, paint-grade
Pine (Natural)$5 – $9$1.50 – $2.70Stained interior accent walls
Cedar$12 – $22$3.60 – $6.60Exterior siding, bathrooms
Hardwood (Oak)$18 – $35$5.40 – $10.50High-end interior feature walls
MDF Shiplap$4 – $7$1.20 – $2.10Budget-friendly dry areas only
Installation Labor$8 – $15 per sq ftProfessional contractor rate

Frequently Asked Questions

Measure your wall width and height in feet, subtract any door or window openings, select your shiplap board size (e.g., 1×6), choose your board length, set a waste factor (10-15% is standard), and click calculate. The tool computes exact board count including waste allowance. The formula is: Total Wall Area minus Openings, divided by Coverage per Board, multiplied by (1 + Waste%).
Standard shiplap has a 1/2-inch rabbet overlap. This means a nominal 1×6 board (actual 5.5 inches wide) covers 5 inches of wall surface per row. The overlap creates the characteristic shadow line and weather-resistant seal. Some premium profiles use a 3/8-inch overlap for a tighter look, but 1/2-inch is the industry standard in the USA.
For straight, simple walls with no obstacles, 10% waste is typical. For walls with corners, windows, doors, outlets, or angled cuts, use 15% waste. For complex gable ends or diagonal installations, consider 20% waste. Always round up to the next full board — you cannot splice shiplap mid-row without visible joints, so partial boards are often wasted.
A nominal 1×6 shiplap board has actual dimensions of 0.75 inches thick by 5.5 inches wide. After accounting for the standard 0.5-inch overlap (rabbet joint), each board covers exactly 5 inches of wall width. This difference between nominal and actual size is standard in USA lumber sizing per NIST guidelines.
A 10×8 wall is 80 square feet. Using 1×6 shiplap (5-inch coverage width) in 8-foot boards, each board covers approximately 3.33 square feet (5 inches x 96 inches / 144). You need 24 boards before waste (80 / 3.33), or 27 boards with a 12% waste factor. At an average of $8 per board, that’s roughly $216 in materials.
Yes, vertical installation is possible and increasingly popular in modern farmhouse and contemporary designs. The calculation method is the same — only the layout direction changes. Vertical shiplap can make ceilings appear taller and works well on narrow accent walls. However, vertical installation may require additional blocking between studs for nailing since each board only catches one stud per horizontal position.
Stud spacing does not affect the board quantity calculation. Shiplap is nailed through the face into studs (typically 16 inches on center), but this doesn’t change how many boards you need to purchase. However, stud spacing does affect fastener count — plan for one nail per stud per row of shiplap.
In 2025, shiplap installation costs vary by region. Materials typically run $1.50-$6.00 per sq ft depending on wood species. Professional labor adds $8-$15 per sq ft. Total installed cost ranges from $13-$27 per sq ft. Pine is the most budget-friendly; cedar and hardwood options cost more but offer superior durability and appearance. DIY installation can save $8-$15 per sq ft in labor costs.

Why Trust This Calculator?

This tool was developed by construction industry professionals with over 20 years of experience in residential woodworking and siding installation across the United States.

Every calculation follows NIST lumber sizing standards and IRC (International Residential Code) guidelines used by American contractors.

Last reviewed and updated: July 12, 2025

NIST Lumber Standards Compliant
Built by USA Construction Experts
IRC Building Code References
50,000+ Calculations Completed

Disclaimer: Results are estimates for planning purposes. Actual material needs may vary based on wall conditions, board quality, and installation method. Always verify with your lumber supplier before purchasing. Prices shown are national averages and may differ by region.