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How We Calculate
Every YardBrick calculator follows the same basic approach. We take the measurements you enter, turn them into an area or a volume, and then convert that into the units you actually buy at the store or order from a supplier.
Our General Approach
- Standard rules of thumb. Formulas follow the methods contractors and trade groups use for estimating: area × depth for bulk materials, wall area minus openings for paint and wallpaper, and so on.
- Manufacturer coverage data. Default values such as bag yields, gallons per square foot, tiles per box or bricks per square foot come from typical manufacturer specifications. Products vary, so most calculators let you change these values.
- Waste factors. Real jobs lose material to cuts, breakage, uneven ground and spillage. Where it matters we add a waste percentage you can adjust, usually 5–15%.
- Rounding up. Bags, boxes, sheets, rolls and bundles are rounded up to whole units, because you cannot buy part of one.
- Estimates only. Results are planning estimates. Always confirm quantities with your supplier, and get a professional for structural, electrical or HVAC design work.
Formulas by Calculator
| Calculator | Formula | Key assumption |
|---|---|---|
| Concrete Calculator | yd³ = L × W × (T ÷ 12) ÷ 27 × (1 + waste) | 80 lb bag ≈ 0.60 ft³, 60 lb bag ≈ 0.45 ft³ |
| Gravel Calculator | tons = L × W × (D ÷ 12) ÷ 27 × density | Density by material, ≈ 1.4 tons per yd³ for crushed stone |
| Mulch Calculator | yd³ = L × W × (D ÷ 12) ÷ 27 | 2–3 in depth; bags in 2 ft³ or 3 ft³ |
| Topsoil Calculator | yd³ = L × W × (D ÷ 12) ÷ 27 | Loose bulk volume as delivered |
| Sand Calculator | tons = L × W × (D ÷ 12) ÷ 27 × density | Sand ≈ 1.35 tons per yd³ |
| Paint Calculator | gal = (wall area − openings) × coats ÷ coverage | ≈ 350–400 ft² per gallon per coat |
| Tile Calculator | tiles = L × W ÷ tile area × (1 + waste) | 10% waste straight, 15% diagonal |
| Flooring Calculator | boxes = L × W × (1 + waste) ÷ ft² per box | Rounded up to whole boxes |
| Fence Calculator | posts = length ÷ spacing + 1; rails = sections × rails per section | Sections = length ÷ post spacing, rounded up |
| Drywall Calculator | sheets = (wall + ceiling area) ÷ sheet area × (1 + waste) | 4 × 8 ft sheet = 32 ft² |
| Roofing Calculator | squares = footprint × pitch factor ÷ 100 | 3 bundles of shingles per square |
| BTU Calculator | BTU/h ≈ floor area × 20, adjusted for sun, occupants, kitchen | ENERGY STAR room AC sizing table |
| Square Footage Calculator | ft² = L × W (triangle ½ × b × h, circle π r²) | Measured in feet |
| Brick Calculator | bricks = wall area × bricks per ft² × (1 + waste) | Modular brick with 3/8 in joints ≈ 6.75 per ft² |
| Paver Calculator | pavers = area ÷ paver area × (1 + waste); base = area × depth ÷ 27 | 4–6 in gravel base, 1 in bedding sand |
| Asphalt Calculator | tons = L × W × (D ÷ 12) × density ÷ 2000 | Compacted hot mix ≈ 145 lb per ft³ |
| Insulation Calculator | thickness = target R ÷ R per inch; area ÷ coverage per bag | R per inch: batts 3.1, loose fill 2.5, spray foam 3.5 |
| Wallpaper Calculator | rolls = (perimeter × height − openings) ÷ usable roll area | Usable area reduced for pattern repeat |
| Deck Calculator | boards = deck width ÷ (board width + gap) × rows; joists = length ÷ spacing + 1 | Joists 16 in on center |
| Grass Seed Calculator | lb = area ÷ 1000 × seeding rate | Rate per 1,000 ft² by species, halved for overseeding |
Corrections
Found an error or a value that doesn't match your product? Read more about our team and contact us.