Measure the Build — free construction calculators for concrete, decking, tile, drywall, roofing, fencing, electrical, paving, masonry, insulation, aggregate, stairs & lumber
Measure the Build is a free US takeoff hub for contractors and DIY homeowners: type your measurements, get the quantity, and see every step of the math — the same way you'd check an estimate. 34 calculators live today across concrete, decking, tile, drywall, roofing, fencing, electrical, paving, masonry, insulation, aggregate, stairs, and lumber. No sign-up, nothing to install. Units are imperial; terminology is US trade vernacular.
Each calculator ships as a static page with the working shown in the HTML. Physical constants — bag yields, board face widths, waste defaults — live in a sourced data layer. When a figure is only a trade convention, the page says so instead of dressing it up as a manufacturer yield.
Manufacturer data sheets · published standards · labeled trade conventions
Calculators
34 tools live today. Each one names its sources and shows the intermediate steps.
Concrete
Concrete Bag Calculator
Cubic feet or yards, then whole bags by size — slab, footing, or post holes
Concrete
Sonotube Concrete Calculator
Cylinder volume and whole bags for round form tubes — with optional center void
Decking
Deck Board Calculator
Board count and material takeoff by brand width, optional even set-out, and waste
Decking
Deck Joist Span Calculator
Maximum joist span and smallest joist size by species, size and spacing from IRC R507.6 — with the full span chart and cantilever limit
Tile
Grout Calculator
Grout pounds from tile size, joint width, and depth — bag count by product
Tile
Tile Calculator
Tile square footage, piece count, and optional boxes for floor, shower, or backsplash
Tile
Shower Tile Calculator
Multi-surface shower takeoff — walls, floor, ceiling, niche, openings, tiles and boxes
Drywall
Drywall Sheet Calculator
Sheet count for walls and ceilings by common US panel sizes
Roofing
Roofing Shingles Calculator
Sloped area and roofing squares from footprint and pitch, then field, starter, and ridge cap bundles at published coverage
Roofing
Roof Pitch Calculator
Pitch, angle, percent slope, and area multiplier from rise and run or a measured angle — plus common rafter length and ridge height
Fencing
Fence Materials Calculator
Posts, post depth, wood pickets, vinyl panels, chain-link mesh, and concrete bags
Fencing
Fence Post Depth Calculator
Compare Quikrete’s ⅓–½ guidance, chain-link baselines, and your local frost or product requirement.
Fencing
Fence Picket Calculator
Picket count with exact gap or even bay spacing, end remainder, and waste
Electrical
Wire Gauge Calculator
Minimum AWG wire size from NEC ampacity and voltage drop, for copper or aluminum, plus a check on a gauge you already have
Electrical
Conduit Fill Calculator
Minimum EMT, PVC or RMC trade size for a mixed conductor pull at NEC fill limits — with the full fill chart
Tile
MAPEI Grout Calculator
Bags or gallon kits of a specific MAPEI grout from that product’s own published coverage table
Tile
LATICRETE Grout Calculator
Bags, cartons or epoxy units of a specific LATICRETE grout from its own published coverage chart
Paving
Asphalt Calculator
Square feet to tons of hot mix or blacktop for a driveway, lot or road — with the density derivation shown, not a single hidden number
Masonry
Brick Calculator
Brick count and cubic feet of mortar for a wall, by US brick size, joint width and bond pattern — from BIA quantity tables
Concrete
Quikrete Calculator
Bags of each QUIKRETE product by every size it is sold in, with total lift weight and spare volume, from the published data-sheet yields
Masonry
Concrete Block Calculator
CMU block count, mortar bags and core-fill grout for a wall, from QUIKRETE published yields and ASTM C90 nominal geometry
Insulation
Insulation Calculator
Blown-in attic bag count by target R-value, from Owens Corning and CertainTeed coverage charts, with the required install depth
Insulation
Wall Insulation Calculator
Batt count and bags for stud walls from measured cavity depth and height, with the R-values that actually fit
Aggregate
Topsoil Calculator
Cubic yards, cubic feet and bag count for lawns, beds and raised beds, with depth presets from NDSU and UMD Extension and a settling allowance
Aggregate
Gravel Calculator
Cubic yards and tons of aggregate for a driveway or base layer, from WSDOT unit dry weights, with the loose delivered volume shown separately
Tile
Thinset Calculator
Bags of thinset from each product’s own published coverage chart, by trowel notch, with back-buttering and overage
Electrical
Box Fill Calculator
Required cubic inches against the box volume, itemised by NEC 314.16(B)(1)-(B)(5), with Table 314.16(A) box sizes
Concrete
Rebar Calculator
Bar counts each way, lineal feet, lap splices, whole stock bars, tie points and total weight from ASTM A615 nominal weights
Stairs
Stair Calculator
Riser height, tread count, total run, stringer length and angle from a floor-to-floor rise, checked against IRC R311.7
Lumber
Board Foot Calculator
Board feet for rough hardwood by the quarter or nominal softwood, with surface measure, cutting overage and optional cost per BF
Roofing
Gutter Calculator
Gutter length, sections, hangers and downspouts, the fall across the run, and the smallest gutter size in IPC Table 1106.6 that carries your roof at your rainfall
Roofing
Soffit Calculator
Soffit area and panel count, plus the IRC R806.2 net free area the attic needs and whether the chosen vented product actually delivers it
Lumber
Plywood Calculator
Sheet count from a real layout rather than area alone, the gap between the two, and the APA span rating that reaches your framing for a floor or a roof
Lumber
Stud Calculator
Common, corner, tee and opening studs for a wall run, plus plate stock lengths, the exact stud cut length, and the precut that fits it
Tile takeoff: Tile Calculator for a single rectangle; Shower Tile Calculator for walls, floor, ceiling, and niche. Fence planning cluster: Fence calculators and material guides.
Why trust the numbers?
Coverage rates and bag yields come from manufacturer data sheets when they exist. Where the trade uses a rule of thumb instead — waste percent, post embedment — that figure is labeled as a convention, not dressed up as a published yield. Conflicts between sources (for example Trex gap figures that disagree across Trex’s own pages) are called out on the tool page instead of silently averaged.
The full source hierarchy and how corrections land is on the methodology page. Who runs Measure the Build and why it exists: about. Questions or a bad constant: contact.
Frequently asked questions
How many bags of concrete do I need for a slab?
Enter your slab dimensions in the Concrete Bag Calculator. It converts cubic feet or yards to whole bag counts by size (40 lb, 60 lb, 80 lb) using Quikrete’s published yields and shows every step of the math.
How do I calculate how many tiles I need?
Use the Tile Calculator for a single rectangle or the Shower Tile Calculator for walls, floor, ceiling, and niche. Both show the waste factor used and label it as a trade convention or a manufacturer figure.
How many deck boards do I need?
The Deck Board & Joist Calculator accounts for brand-specific face widths (Trex, TimberTech, pressure-treated), optional even set-out, and waste — and flags where Trex’s own documents disagree.
What size wire do I need for a circuit?
Enter amps, one-way distance, and conductor material in the Wire Gauge Calculator. It returns the minimum AWG from NEC Table 310.16, checks it against the 210.19(A) voltage drop recommendation, and names which temperature column it applied — terminations usually hold you to the 60 or 75°C value rather than 90°C.
Is Measure the Build free to use?
Yes. Every calculator is free, requires no sign-up, and nothing is installed. Calculator inputs stay in your browser.
More detail: concrete bag calculator, tile calculator, shower tile calculator, and deck board calculator.
Field notes
Longer walkthroughs that sit next to the calculators — not blog filler. For fencing, use the fence hub instead of dumping every post-depth article here.
Concrete
How Many Bags of Concrete Do You Actually Need
Cubic feet to bag counts, when ready-mix beats bagging, and why Quikrete’s two post-depth docs disagree.
Concrete
How Many Bags of Concrete for a Footing?
Trench volume from length × width × depth, Quikrete yields, and when a footing leaves bag territory.
Decking
How Many Deck Boards Do You Need (And Why Brand Actually Matters)
Covered width vs face width, Trex/TimberTech conflicts, and waste that isn’t a brand yield.
Decking
How a Deck Board Calculator Actually Works
Inputs to buy count: dimensions, face width, gap, waste — and why Trex/TimberTech/PT presets disagree.
Decking
How Many Deck Joists Do You Need
Joist count from length and on-center spacing, linear feet of stock, and why spacing follows the board maker.
Decking
Deck Joist Span Chart: How Far Can a Joist Go?
IRC R507.6 spans by species, size and spacing — plus the overhang table, and why the L/4 cantilever rule is wrong in 26 of 36 cases.
Decking
Deck Beam Span Chart: Sizing the Beam and the Posts
AWC DCA 6 Table 3A in full — plus the round-up rule that costs 16 inches of post spacing, and why a solid 4x beats two 2x nailed together.
Drywall
How Many Drywall Sheets Do You Need
Room takeoff with USG 4×8/4×10/4×12 coverage, large openings, and EPD-labeled waste—not a layout optimizer.
Drywall
4×8 vs 4×10 vs 4×12 Drywall
USG face coverage, fewer joints versus carrying weight and access—without inventing mud or screw rates.
Tile
How Many Tiles Do You Need
Area to pieces with labeled floor/wall/diagonal waste conventions—and optional boxes from your carton.
Tile
Tile Waste Factor: How Much Extra?
Why 10/15/20% defaults are trade conventions here—not TCNA yields—and how attic stock differs from cut waste.
Tile
How Much Grout Do You Need
Chart-cell lookup first, calibrated formula only in a documented zone—MAPEI, LATICRETE, TEC, ARDEX.
Roofing
How Many Bundles of Shingles Are in a Square?
Three — but three bundles cover 98.4 sq ft, not 100, for GAF, Owens Corning and CertainTeed. The published numbers, and what the rule of thumb costs you.
Roofing
Roof Pitch Chart: Angle, Slope Factor and Hip/Valley Factor
Every pitch from 0:12 to 24:12 as an angle, a slope percentage, an area multiplier and a hip/valley factor — computed from the geometry, not copied off a PDF.
Electrical
NEC Conduit Fill Chart: How Many Wires Fit in a Conduit
Max conductors by trade size and gauge, derived from NEC Chapter 9 Tables 1, 4 and 5 — including the two-conductor cell where every other chart online is wrong.
Electrical
NEC Wire Ampacity Chart (Table 310.16)
Copper and aluminum ampacity at 60, 75 and 90°C, 14 AWG to 4/0 — plus why the 90°C column is almost never the number you get to use.
Electrical
What Size Wire for 20, 30, 50, 60, 100 or 200 Amps?
The straight answer for each common amperage, the termination rule that decides it, and the run length where ampacity stops being the binding constraint.
Electrical
Voltage Drop Formula: How to Calculate It
The round-trip formula worked by hand, NEC 210.19(A)’s 3% and 5% recommendations, and why they are recommendations rather than code.
Concrete
Sonotube Size Chart: Diameters, Lengths and Concrete Per Foot
Every stock form-tube diameter from Sonoco, QUIKRETE and Sakrete, what each holds per foot, and proof that all three bag charts are the same arithmetic.
Masonry
Brick Sizes: Standard, Modular, Queen and King
Every US brick size from BIA Technical Notes 10 — nominal against specified, what each covers per square foot, and why "standard" and "modular" are not the same brick.