Cedar Siding Calculator
Western red cedar bevel and shingle siding is prized for its natural look, but grade and exposure vary widely. This calculator estimates board count from a typical 12 ft piece at your chosen exposure.
Project type
Wall measurements
Enter each wall's length and height in feet and inches. Wall area = length × height.
Gable ends
No gables added. Gable area = base × rise ÷ 2.
Windows & doors
No openings added. Each opening's area is subtracted from your gross siding area.
Siding material
Waste factor
Waste accounts for cuts at corners and openings, gable angles, damaged pieces, and pattern matching. 10% is a common starting point for a simple rectangular home; complex roof lines or diagonal cuts often need more.
Trim & accessories
Actual accessory requirements vary by installation method and manufacturer — use these as a starting checklist, not a final order.
08Cost estimateOptional
Applied to area including waste — what you'll actually buy.
Applied to net wall area — what installers actually cover, before waste.
Enter your own prices for the most accurate estimate for your area. Leave fields blank or at 0 to exclude them.
Preview
Estimated siding needed
Net area
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Waste added
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Total area (w/ waste)
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Siding squares
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Cedar units
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Est. total cost
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How we calculated this
Trim & accessories
Want professional installation?
Bring this estimate to local siding contractors when comparing quotes, or reach out with questions.
Contact usHow it's calculated
- 1. Net siding area = gross wall and gable area minus openings.
- 2. Required area = net area plus your waste allowance (15% is typical for cedar).
- 3. A single 12 ft piece at a 5 in exposure covers about 5 sq ft.
- 4. Pieces needed = required area ÷ piece coverage, rounded up.
Worked example
A home with 900 sq ft of net wall area and a 15% waste factor:
| Net area | 900 sq ft |
| Plus 15% waste | +135 sq ft |
| Required area | 1,035 sq ft |
| Siding squares | 10.35 squares |
| Pieces to order | 207 pieces |
Cedar grade (clear, knotty) and exposure significantly affect both coverage and cost per square foot.
Assumptions
- • Default piece length is 12 ft with a 5 in exposure — common for cedar bevel siding, but grade and profile vary.
- • Higher-grade clear cedar generally costs more but produces less waste from knot culling.
- • This calculator does not include finishing (stain, sealant) material or labor.
Tips
- • Higher grades of cedar reduce waste from culling knots and defects — factor that into your waste percentage.
- • Cedar siding often benefits from back-priming before installation to reduce moisture-related warping.
Cedar grades, finishes and fasteners
Cedar is graded by how many knots and defects it has. Clear, vertical-grain grades are the most stable and produce the least waste but carry the highest price per board. Knotty grades cost less per board and give a rustic look, but you’ll cull more pieces on site, which is why the 15% waste default is on the higher side. The cedar siding cost page covers how grade and finish move the price.
Finish choice affects both look and upkeep. Untreated cedar weathers to silver-gray, which many people want. If you’d rather keep the warm color, plan to re-coat a stain or sealer on a regular cycle. The right interval depends on the product and how much sun and rain the wall gets, so follow the finish manufacturer’s guidance. Pre-finished boards, coated on all sides at the mill, usually last longer between re-coats than boards finished on site.
Fasteners matter more with cedar than with most siding. Cedar’s natural tannins react with plain steel nails and leave dark streaks, so use stainless steel or hot-dip galvanized fasteners. Also leave room for movement: cedar swells and shrinks with humidity, so nail the way your supplier recommends and don’t over-drive. Comparing cedar with other solid woods? Try the wood siding calculator.
This is a planning estimate
Frequently asked questions
How much cedar siding do I need?
Divide your required siding area by the coverage of a single piece (length × exposure). At 12 ft and 5 in exposure, that’s about 5 sq ft per piece.
Why does cedar siding cost more than vinyl?
Cedar is a natural material with higher material and finishing costs, plus typically higher installation labor than manufactured sidings.
Why do my cedar nails leave black streaks?
Cedar’s tannins react with some metals. Use stainless steel or hot-dip galvanized fasteners to avoid the staining.
How is cedar bevel siding different from cedar shingles?
Bevel siding is a long tapered board installed in courses; shingles are short pieces with a much smaller exposure. This calculator is built around bevel-style boards, so use shingle coverage from your supplier if you’re installing shingles.
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Related guides
Siding Waste Factor Explained
Why waste percentage matters and how to choose the right one for natural materials.
How to Measure a House for Siding
Walls, gables, openings and trim, step by step.
How Much Does Siding Cost?
Typical installed prices and what moves a quote.
Siding Cost Per Square Foot
What drives price per square foot across materials.