Convert house footprint dimensions and roof pitch (1/12 to 12/12) into true sloped roof area, roofing squares, shingle bundles, underlayment rolls, ridge cap, and replacement cost.
| Material / Application | Standard Spec / Depth | Coverage / Weight | Field Note |
|---|---|---|---|
| 2/12 Pitch (Low slope) | 9.5° (16.7% grade) | × 1.014 multiplier | Walkable · requires double underlayment / membrane |
| 4/12 Pitch (Standard ranch) | 18.4° (33.3% grade) | × 1.054 multiplier | Easily walkable · minimum for standard shingles |
| 6/12 Pitch (Classic gable) | 26.6° (50.0% grade) | × 1.118 multiplier | Max comfortable walkability without roof jacks |
| 8/12 Pitch (Steep gable) | 33.7° (66.7% grade) | × 1.202 multiplier | Steep · requires roof brackets & harness |
| 10/12 Pitch (Architectural steep) | 39.8° (83.3% grade) | × 1.302 multiplier | Very steep · +20% labor surcharge |
| 12/12 Pitch (45° A-frame/Tudor) | 45.0° (100% grade) | × 1.414 multiplier | Extreme slope · 41.4% more roof area than footprint |
Free cubic yard and tonnage calculator for gravel, concrete, mulch, asphalt, roofing, pavers, cinder blocks, topsoil, and paint. Multi-zone builder + printable estimate sheet.
Instant gravel calculator in tons, cubic yards, and 50-lb bags. Supports multiple driveway zones, compaction allowance, pea gravel vs #57 crushed stone densities, and bulk vs bag cost.
Free concrete calculator for slabs, patios, driveways, footings, and round sonotube post holes. Shows cubic yards, 80-lb and 60-lb bag counts, short-load truck fees, and rebar estimate.
Free mulch calculator and estimator: convert flower bed dimensions and tree rings into cubic yards, 2 cu ft bags, and 3 cu ft bags. Compares bagged vs bulk mulch delivery costs.
Accurate asphalt calculator in US tons and cubic yards. Uses standard 145 lb/ft³ hot-mix density, roll-down compaction guide, cold-patch 50-lb bag count, and hot-mix plant cost.
Complete patio paver calculator: computes paver count for 4x8 brick, 6x9, 12x12, 16x16, and 24x24 slabs plus crushed gravel base tons, leveling sand bags, and polymeric sand.
Free concrete block calculator and cinder block calculator. Computes 8x8x16 CMU blocks (1.125 per sq ft), courses, 80-lb mortar bags, core fill grout, and concrete footing.
Free paint coverage calculator: enter wall dimensions, doors, windows, coats, and surface texture to get exact gallons, liters, primer needs, and 5-gallon vs 1-gallon can savings.
Free topsoil calculator and sod calculator: convert lawn or raised garden bed dimensions into cubic yards, tons, 40-lb bags, and sod pallets.
In roofing, 1 "square" equals 100 square feet of roof surface. Standard 3-tab and architectural asphalt shingles are packaged so that 3 bundles cover 1 roofing square (33.3 sq ft per bundle). Heavyweight luxury shingles require 4 to 5 bundles per square.
Add your eave overhang to the footprint length and width, multiply to get flat area, then multiply by the roof pitch factor: √(1 + (Rise ÷ 12)²). For example, a 6/12 pitch has a factor of 1.118 (11.8% larger than flat), while a 12/12 pitch has a factor of 1.414.
A simple two-sided gable roof requires 10% waste. A hip roof or roof with multiple dormers, valleys, and hips requires 12% to 15% waste due to diagonal cuts along hips and valleys.