Lumber & woodworking guides

Board feet are to lumber what gallons are to paint — the volume unit that lets you compare apples to apples across species, sizes and suppliers. A 2×4×8 is always 5.33 board feet whether it costs $3.50 or $14.00 per BF. The formula is simple: thickness in inches times width in inches times length in feet, divided by 12. But simplicity hides nuance: which dimensions do you plug in, and why does one calculator give a different answer than your supplier?

The answer almost always comes down to nominal versus actual sizes. Softwood framing lumber is priced by nominal dimensions — 2×4, 2×6, 2×12 — even though its dressed size after planing is smaller. Hardwood is almost always quoted by actual (dressed) size. This series explains the PS 20-25 American Softwood Lumber Standard, shows the nominal-to-actual conversion table, and walks through why the same physical board can produce two very different board-foot totals depending on the convention you follow.

The guides also cover how board feet differ from linear feet and cubic feet — three measurements that get mixed up on every jobsite. Linear feet measure length only, cubic feet measure physical volume, and board feet measure billable volume under the PS 20-25 convention. Knowing which one your supplier is quoting lets you sanity-check every invoice.

The siding coverage formula is one of the more counterintuitive calculations in lumber estimating: Linear Feet = (Area in sq ft × 12) ÷ Exposed Face Width in inches. A 200-square-foot wall with 1×6 bevel siding, whose exposed face is 5.5 inches after overlap, needs 436 lineal feet — not 400 as you might naively assume from the 6-inch nominal width. That 0.5-inch overlap matters on every board.

This series covers every siding profile and its standard exposed width: bevel siding (typically ½ inch overlap), board-and-batten (nominal minus one batten width), tongue-and-groove (smaller gap from the tongue thickness), and lap siding with its own overlap rules. Each profile has a coverage table you can read across instead of plugging into a calculator every time.

We also cover how to account for waste in siding calculations. Standard waste is 10%, but angled gable ends, intricate dormer cuts, and projects where you are trying to match grain can push that to 15%. The guides show when to add waste as extra lineal feet versus extra whole boards, and why the coverage calculator rounds up differently for siding than it does for framing.

The calculator's built-in species presets give national-average board-foot prices — SPF at $3.50/BF, Douglas Fir at $4.20, Red Cedar at $5.80, Red Oak at $7.50, Hard Maple at $9.00, Cherry at $10.50, and Black Walnut at $14.00. But these are starting points, not final numbers. Regional differences, grade, moisture content, and current market conditions all shift the real-world price you will pay.

This series covers each major species in context: SPF for budget framing, Douglas Fir for load-bearing members, Red Cedar for outdoor siding and decking, Oak and Maple for furniture and flooring, Cherry and Walnut for premium woodworking. For each species we explain its Janka hardness, workability, finish characteristics, and which projects it excels at (or struggles with).

Price-per-covered-foot comparisons are a major theme. A $10.50/BF Cherry board might actually cost less per finished surface than a $14.00/BF Walnut board once you account for waste, yield, and cut efficiency. The guides show how to build that comparison table yourself, so species selection becomes a decision rather than an upsell.

The calculator's waste factor defaults exist for real reasons — the equipment and technique you use. A circular saw with a standard blade kerf wastes less than a band saw, but the band saw produces more usable offcuts. A miter saw for trim creates zero kerf waste on crosscuts but loses material to miter joints. This series explains where waste actually goes: kerf losses, blade thickness, rip versus crosscut efficiency, and the technique habits that keep real-world usage close to the estimate.

Equipment guides follow: choosing blade tooth count by cutting task, saw guide use for repeatable cuts, jig and fixture tricks that reduce measurement error, and when a table saw stops being a luxury. Each guide closes the loop by naming the waste-factor adjustment the tool deserves — a carbide-tipped blade on a table saw can legitimately use a 5% waste factor on certain jobs, while a cheap blade used freehand on hardwood needs 25%.

Measurement technique matters too. Tape measure accuracy, marking methods, and layout order all affect final waste. The guides explain how experienced carpenters lay out cuts before picking up a saw, and how to mark boards so you don't accidentally cut the wrong end. The fastest way to waste lumber is to cut the wrong board — and that's a technique problem, not a math one.