Site & Sustainability Calculators
27 free site & sustainability calculators — standards-based, with formulas, worked examples, and no sign-up.
This is the broadest category on the site because it collects what a real project needs beyond the engineering disciplines: material takeoffs, site safety, accessibility, and the money and carbon math that decide whether the project happens. The estimating cluster is the largest — drywall sheets with mud, tape, and screws; tile with pattern-dependent waste and thinset by trowel notch; paint and primer gallons at real spread rates; flooring boxes with layout waste; siding squares; fences post by post; paver patios with base and bedding sand; decking boards and fasteners; carpet from actual broadloom roll geometry with seam placement; plus wallpaper, baseboard, gravel, sod, driveway sealer, and mulch. Each is anchored to published coverage data or the trade's counting rule, rounds purchases buyer-friendly (up, in whole units), and states its waste assumptions instead of hiding them.
The compliance-and-safety tools carry the codes their names cite. Trench excavation applies the OSHA 1926 Subpart P maximum allowable slopes by soil type and computes bank and spoil volumes with safety flags; temporary works (scaffolding, formwork, shoring) follows BS 5975 and OSHA 1926; rigging sling loads resolve tension per leg with the angle factor that surprises everyone the first time; stairs are checked against IBC, IRC, and OSHA geometry plus the Blondel 2R+T comfort rule; ADA ramps against the 1:12 slope and the landing requirements of 405.6; baluster spacing against the IRC 4-inch sphere rule; and grading against the IRC R401.3 foundation drainage minimums.
The sustainability pair takes the long view: embodied carbon per EN 15978 across lifecycle stages A1–D with a 201-material database and benchmark comparisons, and life-cycle cost as NPV, payback, and savings-to-investment ratio — the tools for arguing that the cheaper-today option is not the cheaper option. The window fabrication calculator, the site's original tool, still lives here with its cutting-list optimizer.
All Site & Sustainability Tools
Window Fabrication Calculator
Cutting lists and fabrication drawings for aluminum windows with optimized material usage.
Embodied Carbon Calculator
Whole-life carbon emissions with lifecycle assessment across stages A1-D per EN 15978.
Temporary Works Design
Scaffolding, formwork, and shoring load checks with stability analysis for construction.
Earthwork Cut & Fill Calculator
Cut and fill volumes by average-end-area and prismoidal methods with shrinkage and haul balance.
Life-Cycle Cost Calculator
LCCA with NPV, simple and discounted payback, and savings-to-investment ratio for two options.
Stair Calculator (Rise, Run & Code Check)
Straight-flight stair design from the floor-to-floor rise: number of risers, actual riser height, treads, total run, stair angle and stringer length, checked against IBC, IRC, OSHA or custom riser and tread limits and the Blondel 2R + T comfort rules.
Rigging Sling Load Calculator
Lifting sling tension per leg from load weight, leg count and sling angle from horizontal, with the angle factor, required WLL per leg for vertical, choker and basket hitches, horizontal compression on the load, and OSHA / ASME B30.9 sling-angle warnings.
Gravel & Aggregate Calculator
Cubic yards, cubic metres, and tonnage of crushed stone, pea gravel, sand, crusher run, riprap, or topsoil from rectangular, circular, or direct areas. Compaction and waste allowances with bag counts and 10 yd³ truckloads.
ADA Ramp Slope Calculator
Accessible ramp design per the 2010 ADA Standards and ICC A117.1: required run at 1:12, 1:16 or 1:20 (plus the 1:10 and 1:8 existing-site exceptions), intermediate landings from the 30 in rise limit, total footprint, handrail flag, and a check mode that grades an existing rise and run with pass/fail margins.
Decking Board & Fastener Calculator
Deck board and fastener quantities from the footprint: rows from the board width plus gap (5.5 in and 3.5 in presets or custom), lineal footage with a 10% straight or 15% diagonal waste allowance, boards to buy at 8 to 20 ft stock lengths, and face screws at two per joist crossing or hidden clips at one per crossing plus a starter per row, with 100/350/1750-count box suggestions.
Baluster Spacing Calculator (IRC 4-Inch Rule)
Guard baluster layout under the IRC R312.1.3 4-inch-sphere rule: the minimum number of balusters for a clear opening between posts, the perfectly even clear gap with a pass/fail badge, and center-line layout marks measured from the post face, plus an as-built check mode that verifies an existing baluster count and reports the margin to the 4-inch limit or a custom maximum such as the 4-3/8-inch allowance for guards on the open sides of stairs.
Drywall Calculator (Sheets, Mud, Tape & Screws)
Drywall quantity takeoff for a rectangular room (with or without the ceiling) or a list of wall segments, subtracting door and window openings. Counts 4x8, 4x10, or 4x12 sheets at 10% standard or 15% complex waste and converts representative trade coverage rates into joint compound pounds and 4.5-gallon buckets, tape lineal feet and 500-ft rolls, screws and 1000-count boxes, plus 8-ft corner bead sticks from the entered outside-corner footage.
Tile Calculator (Tiles, Thinset & Grout)
Tile quantity takeoff for a floor or wall entered directly in square feet or as length by width: tiles and boxes from the effective footprint of each tile including its grout joint, with pattern waste at 10% straight or offset, 15% diagonal, and 20% herringbone. Counts 50-lb thinset bags from representative 1/4, 3/8, or 1/2 inch square-notch trowel coverage and grout pounds from the industry-standard joint-geometry formula, rounded into 10-lb and 25-lb bags.
Fence Calculator (Posts, Rails, Pickets & Concrete)
Wood fence material takeoff from the run length: posts and sections at 6 or 8 ft on center, rails per section by style (3 privacy, 2 picket, 2-3 post-and-rail), pickets from the picket width and gap, post length to buy rounded to even-foot stock from the trade 1/3-height bury rule (2 ft minimum), post holes at three times the post width over a 4-inch gravel base, and concrete per hole and total with 60-lb and 80-lb premix bag counts plus one extra post and hardware set per gate.
Paver Patio Calculator (Pavers, Base & Sand)
Interlocking concrete paver takeoff for patios, walkways, and driveway aprons: pavers to buy from 4x8, 6x6, 6x9, 12x12, or custom face sizes with pattern waste (5% running or stack bond, 10% herringbone, 15% circular), compacted aggregate base at 4-in pedestrian or 8-in vehicular depth with a 1.15 loose-to-compacted factor, bedding sand at the fixed 1-inch ICPI screed, polymeric jointing sand bags at representative 80 ft² coverage, and 8-ft edge restraint sticks along the open perimeter.
Siding Calculator (Squares, Planks & Trim)
Horizontal lap-siding takeoff from up to 20 wall elevations with door and window openings subtracted: siding squares and course-equivalent lineal feet at trade-practice exposures (8.25-in plank at 7-in exposure, 6.25-in at 5-in, or a custom 3-12 in) with 10% simple or 15% complex waste, 12-ft or 16-ft plank counts, housewrap rolls figured on the gross area because the wrap runs behind the opening flanges, starter strip along the wall bases, and 10-ft corner trim sticks from the corner count and height.
Trench Excavation Calculator (OSHA Slopes & Spoil)
Trench excavation takeoff with sides at the OSHA maximum allowable slope from 29 CFR 1926 Subpart P, Appendix B, Table B-1 (excavations under 20 ft): stable rock vertical, Type A 3/4:1, Type B 1:1, Type C 1.5:1 by the competent-person soil classification, top width at grade and trapezoidal cross-section, bank volume in cubic yards, loose spoil from representative swell presets (15% rock, 30% Type A, 25% Type B, 12% Type C) or a custom 0-60% override, 10-yd³ truckloads, and the two Subpart P safety flags: protective system required at 5 ft or deeper per 1926.652(a)(1) with the stable-rock exception, and egress within 25 ft of lateral travel at 4 ft or deeper per 1926.651(c)(2).
Baseboard & Trim Calculator
Baseboard and trim takeoff for up to 20 rooms: installed lineal feet per room as the rectangular perimeter minus the standard 3-ft deduction per door opening (floored at zero for door-heavy closets, never negative), a 10% waste allowance for miters, copes, and splices, whole-stick purchase counts for 8-, 12-, and 16-ft stock, painter's caulk at one tube per 40 lineal feet of the INSTALLED length because waste offcuts are never caulked, and inside/outside corner counts echoed with the finish-carpentry joinery advisories — cope the inside corners so joints stay tight through seasonal movement, miter the outside corners at 45 degrees.
Flooring Calculator (Boxes, Waste & Underlayment)
Plank and laminate flooring takeoff: net floor area from up to 20 rooms minus up to 20 exclusions (kitchen islands, hearths, built-ins), boxes to buy from the coverage printed on the product carton (default 22 ft² — representative only) with a waste allowance keyed to the installation layout (10% straight, 15% diagonal, 20% herringbone/parquet), underlayment counted as 100-ft² rolls on the net area without the layout waste, an optional cost estimate from a price per box, and a chart comparing the box count across all three layouts.
Grading & Drainage Slope Calculator (IRC R401.3)
Foundation drainage grade check per the IRC 2021 published text (source-verified): the ground surface must fall not fewer than 6 in within the first 10 ft of the foundation (R401.3, a 5% equivalent), impervious surfaces within 10 ft of the foundation sloped not less than 2% away from the building per the R401.3 Exception, and drains or swales where lot lines, walls, slopes, or other physical barriers prohibit the fall — pass/fail verdict with the margin in inches and the governing section reference, the required fall for any run at the governing rate with a first-10-ft caveat for longer runs and the swale/drain note for shorter ones, plus a slope converter between percent, inches per foot, and 1:N ratio with exact round-trips (5% = 0.6 in/ft = 1:20, 2% = 0.24 in/ft = 1:50).
Sod & Grass Seed Calculator
Lawn establishment estimator with sod and seed modes: sod mode converts lawn area into standard 2 ft × 5 ft (10 ft²) rolls with a 5% or 10% cutting-waste allowance and into pallets at your supplier's stated coverage (300–700 ft² input, 450 default — pallet coverage varies by supplier, so it is asked, not assumed); seed mode computes pounds of grass seed from rates verified against University of Tennessee Extension W160-B "Turfgrass Establishment: Seeding" (table midpoints: Kentucky bluegrass 1.75, tall fescue 6.5, perennial ryegrass 5, hulled bermudagrass 0.75 lb per 1,000 ft²) at full rate for a new lawn or half rate for overseeding an existing thin stand, both modes adding starter-fertilizer bags at a representative 5,000 ft² per bag sized on the bare ground area rather than the waste-adjusted sod order, with the reminder that rates vary by cultivar and region — follow your seed bag and local extension.
Dumpster Size Calculator (Volume & Weight)
Roll-off container sizing from a list of demolition projects: representative debris factors for roof tear-off by squares and shingle layers (1/3 yd³ + 240 lb per square per layer — the encoded 240 lb is the midpoint of the published 230–250 lb/square trade range for 3-tab, architectural runs heavier), drywall (0.2 yd³ + 220 lb) and flooring (1/3 yd³ + 150 lb) per 100 ft², deck removal (1 yd³ + 300 lb per 100 ft²), kitchen (3 yd³ + 1,500 lb) and bath (1.5 yd³ + 800 lb) demo per room, plus custom per-unit debris, with loose volume at a 15% fluff factor and weight never fluffed, checked against 10/20/30/40 yd³ containers with representative 1–4 ton rental weight allowances — one size step up when weight alone overflows, split-load guidance when heavy debris like shingles governs by weight, and a chart of the load against every container allowance, all framed as estimates to confirm with your hauler (overage fees and prohibited items vary).
Paint Calculator (Gallons of Paint & Primer)
How many gallons of paint a room needs: wall area from room dimensions (perimeter × ceiling height) or a direct square-footage entry, doors and windows deducted at editable representative areas (21 ft² per door, 15 ft² per window) plus a custom exclusion, an optional ceiling, 1–3 coats at a spread rate set from your can (representative default 350 ft²/gal — manufacturers publish 350–400 for smooth, sealed surfaces), and an optional single primer coat at its own rate, with whole-gallon buy counts and a paintable-area breakdown.
Wallpaper Calculator (Rolls by Pattern Repeat)
How many rolls of wallpaper a room needs: wall area from the perimeter × wall height with openings deducted, usable coverage per single roll from the wallcovering trade's pattern-repeat yield table (no repeat or up to 6″ = 25 ft², 7–12″ = 22 ft², 13–18″ = 20 ft², 19–23″ = 18 ft² — verified against Hirshfield's wallcovering estimating guide), whole single- and double-roll counts, and a purchase quantity in the format your paper actually sells in (most US wallpaper sells as double rolls), with a leftover-coverage note.
Carpet Calculator (Broadloom Strips, Seams & Waste)
How much broadloom carpet a set of rooms needs, with the waste emergent from roll geometry instead of a flat percentage: each room buys whole strips of the 12- or 15-ft roll (ceil of room width ÷ roll width, strips running along the room length), so the calculator reports carpet bought vs laid per room and in total, the resulting waste percentage, seam counts, pad square footage on the laid area, tack strip from the room perimeters minus a per-room doorway allowance, and an optional straight stair flight from steps × width × (tread + riser + 1″ nose) geometry.
Driveway Sealer Calculator (Pails by Surface Condition)
How many 5-gallon pails of driveway sealer an asphalt driveway needs: area from length × width or a direct square-footage entry, first-coat coverage picked by surface condition (representative 450/350/300 ft² per pail for smooth/aged/rough — midpoints of the Latex-ite Airport Grade datasheet's published 400–500 and 300–400 ft² ranges), a second coat at the previously-sealed rate because coat one seals the surface, whole pails pooled across both coats, and optional 1-gallon crack-filler jugs at a representative 75 LF per jug for 1/2″ cracks, with the 24–48 h cure window and 55 °F application minimum noted.
Mulch & Topsoil Calculator (Bags vs Bulk)
How much mulch, topsoil, or compost a set of beds needs: cubic feet and cubic yards from up to 20 beds (L × W) or a direct total area and a spread depth with per-material guidance (mulch 2–3″, new lawn topsoil 4–6″, patching 1–2″), whole 2 or 3 ft³ bag counts rounded buyer-friendly, load weight in pounds and US tons from representative densities framed as ranges (hardwood mulch 600 lb/yd³ of 400–800, screened topsoil 2,200 of 2,000–2,400, compost 1,300 of 1,000–1,600), and bagged-vs-bulk purchase totals side by side when prices are entered — gravel and stone mulch are referred to the gravel & aggregate calculator.
Frequently Asked Questions
Why do the estimators give different waste percentages for the same square footage?
Because waste is a property of the material and layout, not the room. Tile waste depends on pattern (a diagonal or herringbone layout cuts more), flooring waste on plank direction versus room shape, carpet waste on how 12-ft broadloom strips and seams fall in your rooms — the carpet tool actually lays out the strips rather than applying a flat percentage. Trusting one universal waste factor is how projects end up one box short on a discontinued dye lot.
The trench tool says I need a much wider excavation than the pipe needs. Why?
OSHA 1926 Subpart P requires trench walls deeper than 5 ft to be sloped, benched, or shored. In Type C soil (the default assumption for anything you have not classified), the maximum slope is 1.5:1 (horizontal:vertical) — so a 6-ft-deep trench needs to open roughly 9 ft on each side beyond the bottom width, tripling the excavation and the spoil pile. The calculator shows the volume consequence of each soil type, which is also the cost argument for a competent-person soil classification or a trench box.
Life-cycle cost and embodied carbon — do they ever point in different directions?
Regularly, and that is why both tools exist. Extra insulation usually wins on both counts, but carbon-intensive products with long service lives (some metals, concrete) can look good on NPV and poor on A1–A3 emissions, while low-carbon options may carry higher first cost that the LCC tool can test against energy savings and your discount rate. Running both makes the trade-off explicit instead of rhetorical.