Vertical: General Contractor · Nav: 🏗️ GC Tools · This article: Tabs 1–4 of 9
Part 2: Labor, Sub Markup, Permit, Room Scan & Good/Better/Best →
GC Tools is a nine-tab calculator suite for general contractors. This article covers the four takeoff and measurement tabs. For labor, subcontractor markup, permits, room scan, and the Good/Better/Best tier builder, see Part 2.
Tab 1 — Concrete Yardage #
Calculates cubic yards of concrete needed for a pour. In Dimensions, enter Length, Width, and Depth / Thickness (in inches), plus a Waste factor percentage. The result section shows net cubic yards and yards with waste — the number to actually order. A bag count for hand-mixing appears for reference. The footer is direct: “Order ready-mix in cubic yards. Add at least 10% waste for slabs — more for irregular pours. Bag counts are for hand-mixing reference only.”
Tab 2 — Lumber Board Feet #
Calculates board feet for a lumber order. In Lumber Pieces, each row takes Length (ft), Width (in), Thickness (in), and Quantity. The tab footer shows the formula: “Board feet = length (ft) × width (in) × thickness (in) ÷ 12.” Tap Add Piece to add each piece dimension — mix different sizes freely. In Cost & Waste, enter your Price / board foot and a Waste factor percentage. Results show total board feet, board feet with waste, and total material cost.
Tab 3 — Area Calculator #
A flexible area calculator for any named space. Each row in Rooms & Areas takes a name plus Length and Width in feet. Add as many areas as the job requires. If you’ve run a LiDAR scan in the Room Scan tab, an Import button appears on the relevant row — tap it to pull the scanned floor area directly into the field (changes to “Imported ✓” when done). In Waste Factor, add an overage percentage. The footer reminds you: “Use ‘Measure on Map’ to trace a space from satellite imagery. Import a LiDAR scan from the Room Scan tab to auto-fill floor area.”
Tab 4 — Pitch / Slope #
Converts a roof or ramp pitch into the slope multiplier needed to get true surface area from a flat footprint. In Pitch (Rise : Run), enter your rise and run values and tap Use — the slope multiplier calculates and is applied to the flat footprint input below. Quick Reference — Common Pitches lists standard pitch values so you can tap a known pitch without measuring. Enter the Flat footprint in square feet and the Adjusted Roof Area section shows the true surface area for material ordering. The footer explains the math: “Slope multiplier = √((rise/run)² + 1). Multiply your flat footprint by this value to get the true roof surface area for material ordering.”
