Guides
Construction estimating guides and reference charts
Each guide explains one estimating task: how the numbers are worked out, a reference table built from the same formulas the calculators use, a worked example, and the mistakes that cause short orders or failed inspections. Every guide links to the matching calculator.
Guides are general reference material. Local code, the engineer of record, and manufacturer instructions take precedence. See the editorial policy for sources and how corrections are handled.
Concrete
Concrete Yardage Chart: Slab Volume, Bags, and Truck Loads
A slab volume chart in cubic yards and 60 lb / 80 lb bags by size and thickness, plus how to order ready-mix, what to add for waste, and where short loads cost extra.
October 2, 2026 · 7 min readReinforcing steel
Rebar Size and Weight Chart (#3 to #11) with Lap and Cover Rules
Diameter, weight per foot, and area for ASTM A615 rebar #3 through #11, with weights for common slab grids, lap splice rules of thumb, and concrete cover requirements.
October 2, 2026 · 7 min readStairs
IRC Stair Requirements: Rise, Run, Headroom, and Handrails Explained
The IRC R311.7 stair limits in plain terms: maximum riser, minimum tread, headroom, width, nosing, handrail height, and how to lay out a stair that passes inspection.
October 2, 2026 · 8 min readRoofing & framing
Roof Pitch Chart: Angle, Slope Multiplier, and Rafter Length per Foot of Run
A roof pitch chart from 1:12 to 18:12 with angle, percent grade, slope multiplier, and rafter length per foot of run, plus minimum pitch limits for common roof coverings.
October 2, 2026 · 7 min readInterior finish
How Much Drywall to Order: Sheets, Screws, Tape, and Joint Compound
How to count drywall sheets for walls and ceilings, which sheet length to buy, and how much screws, tape, and joint compound a room needs, with sample room takeoffs.
October 2, 2026 · 7 min readRoofing & framing
Roofing Squares and Bundles: How to Order Shingles for Any Roof
What a roofing square is, how pitch and roof shape change the shingle count, and how to order bundles, underlayment, starter, and ridge cap with sample takeoffs.
October 2, 2026 · 7 min readMasonry
Brick and CMU Block Quantities per 100 Square Feet of Wall
Units per square foot for modular brick, queen, king, and CMU block, with mortar and sand allowances, opening deductions, and how joint thickness changes the count.
October 2, 2026 · 7 min readEstimating
Construction Waste Factors by Material: What to Add and When
Typical waste percentages for tile, flooring, drywall, concrete, siding, and masonry, what pushes each one higher, and how to avoid adding waste twice.
October 2, 2026 · 6 min read