Measurements, coverage and rounding
The starting measurements are editable examples, not measurements of a real home. Change them to match your project. Coverage, extra material and package sizes stay editable because different products and layouts need different amounts.
The calculation beside each result shows the arithmetic. We keep the underlying area or volume before rounding the order up to whole boxes, bags, bundles or cans. A blank price stays unknown.
Units and rounding
Bare lengths use the unit on their field. Feet-and-inches entries such as 12 ft 6 in and 150 in are converted to the same length as 12.5 ft. Tube diameters and height use inches; the other concrete shapes label their long dimensions and thickness separately. Lengths are converted to feet before area or volume arithmetic. Roof area equals horizontal footprint area multiplied by the square root of 1 + (rise divided by run) squared. For a 6:12 pitch, that ratio is 6 divided by 12. An allowance increases the material quantity by the percentage you choose. Boxes, bags and bundles round up; the underlying area does not. The shingle example displays 33.3 sq ft per bundle but calculates with exactly 100/3 until you edit it. Split very large projects into smaller parts, and check the units if a dimension is refused.
Gates, slopes and roof panels
Fence gate positions and section lengths are horizontal distances between post centers. Each section has a constant slope: slope length is the square root of horizontal length squared plus rise squared. The gate splits solid fence into separate spans; each span is divided into equal bays no longer than the entered maximum spacing along the slope. A shared post is counted once. Grade-change posts are treated as terminals for chain link; the supplier still needs to specify the grade and gate fittings.
Metal panels use the entered width minus side lap. Enter an already installed coverage width with a zero side-lap deduction. Eave, rake, ridge, hip and valley trim round separately using each part’s usable coverage. Full-length panels are assumed; the calculation does not design end laps or optimize offcuts.
Drywall is an area-based sheet allowance. It does not lay sheets across framing or prove that an offcut can be reused. Check orientation, joint support and openings on a sheet layout before ordering.
Quote totals and allowances
A quote budget adds the entered price, work or fees left out, and any additional tax. The reserve percentage applies to that subtotal. It is an amount you choose to set aside, not a market-price estimate or a recommended reserve. Blank prices remain unknown.
Starting dimensions, counts, gaps and allowances are arithmetic examples, not observed homes or installation requirements. The product and guide facts identified on the source list have their own links, periods and Updated dates. Change the examples to match your measurements and the selected products.
What these numbers cannot settle
The calculators cannot inspect rotten decking, confirm load paths, select a beam span, locate utilities or decide permits. AHS medians are past spending across different jobs. BLS figures are employee pay, without contractor overhead or a project’s labor hours. Neither is your local quote.
Product coverage and reference values
These references explain the product examples and unit conversions used by the calculators. Check the label or specifications of the material you plan to buy.
Sherwin-Williams: How to Prep Walls for Painting
Preparation, room protection, cleaning, patching, caulking and priming. The process guide also follows the manufacturer’s warning about disturbing old coatings.
Schluter-DITRA Installation Handbook
Assembly selection, waterproofing connections and movement-joint requirements for the named system. No structural sizing or universal shower assembly is supplied.
USG Sheetrock Installation and Finishing Guide J371
Panel planning, hanging, compatible joint treatment, drying between coats and repair sequence. The guide does not select a rated assembly.
USG: Repair Drywall
Like-material repairs to fire-rated assemblies and the manufacturer’s reference to Gypsum Association GA-225.
GAF Technical Advisory Bulletin R-136: Valley Flashing Options
System-specific valley choices: laminated Timberline shingles use open or closed-cut valleys rather than woven valleys.
GAF Steep-Slope Pro Field Guide
Roof-system planning: deck, underlayment, flashing, ventilation and product-specific fastening. The homeowner guide does not provide a roof-access method.
Barrette Outdoor Living: Veranda Vinyl Fence Installation Instructions
Panel/post geometry and shortened sections for the named vinyl system. Its foundation dimensions are not treated as national defaults.
Unit conversion
Exact conversion: 1 foot = 0.3048 meter; a cubic yard is 27 cubic feet; 1 US gallon = 3.785411784 liters and a quart is a quarter gallon. Other areas and volumes are derived from these units.
GAF Timberline HDZ specifications
The listed 3 bundles per roofing square gives 100/3 square feet per bundle for the editable shingle example. Check the selected package.
GAF explanation of roofing squares
A roofing square is 100 square feet. Bundle coverage varies by product.
Sherwin-Williams paint questions
The example uses theoretical coverage of 400 square feet per gallon. Actual coverage depends on coating and surface. Primer uses a separate illustrative coverage input and must be checked against its own label.
Basalite CMU dimensions: Rocks in a Box
The Dimensions section specifies a precision CMU as 7 5/8 inches wide, 7 5/8 inches high and 15 5/8 inches long. The example uses that face size; actual units have manufacturing tolerances. Adding the chosen 3/8-inch joint gives a 16 by 8-inch repeating position.
AWC DCA6 deck guide, 2018 edition based on the 2015 IRC
Page 20, Figure 27 states the maximum riser and minimum tread. The stair example starts with a 7 3/4-inch maximum riser and 10-inch tread run. These are editable reference values, not a finding about the code adopted at a particular address. No beam, joist or stringer sizing is supplied.
QUIKRETE Concrete Mix No. 1101 data sheet
The YIELD section on page 1 gives approximate mixed volumes: 80 lb = 0.60 cubic feet, 60 lb = 0.45 cubic feet, and 40 lb = 0.30 cubic feet. The selectable examples use these values; other mixes and bag sizes require the yield on their own label.
GAF Royal Sovereign shingles: specifications
The 3-tab choice uses the page’s specification table: its Bundles/Square row reads 3, which is 100/3 square feet per bundle, and its Exposure row reads 5 inches.
GAF: Minimum slope for shingles
The roofing calculator warns when an asphalt shingle section is below 2 in 12, the minimum GAF gives. Shingles on low slopes also need the maker’s low-slope underlayment details.
Cedar Shake & Shingle Bureau: New Roof Construction Manual, coverage tables
The cedar choices use the bureau’s coverage tables: one square is 4 bundles of 16-inch shingles at a 5-inch exposure (25 square feet per bundle), and 5 bundles of shakes at a 7 1/2-inch exposure (20 square feet per bundle). Other lengths and exposures cover differently.
Eagle Roofing Products: technical specifications
The concrete tile choice uses Eagle’s Malibu profile: 88 field tiles per 100 square feet with a 3-inch headlap. Ridge, rake and starter pieces are separate items.
Barrette Outdoor Living: Veranda Vinyl Fence special order catalog
The vinyl fence calculator starts with the Linden 6 ft by 8 ft kit, whose actual width is 91 inches, and 5 by 5-inch posts. Veranda’s assembly instructions set post centers at the panel width plus the post width (96 inches here), and a shorter bay takes a cut-down panel.
Fortress Building Products: Athens aluminum fence installation instructions
The aluminum fence calculator starts with the maximum post spacing Fortress gives for 2-inch posts, 71 3/4 inches on center. The instructions say panel lengths are adjusted at gates, to cut an equal amount from each end of a shortened panel, and that gate posts sit 1 1/4 to 2 1/4 inches wider apart than the gate panel. Its figure for 2 1/2-inch posts is not used because the document gives two different values.
AWC DCA 6 deck guide: guard requirements
The railing calculator keeps every baluster gap under 4 inches. Page 19 says openings must not let a 4-inch sphere pass. Local codes set the rule where you live.
AWC DCA 6 deck guide: Figure 24, example guard detail
The railing calculator starts with posts at most 6 feet apart, the spacing labeled on the example guard in Figure 24 on page 19. The label is part of the drawing, not the text. Your railing system may set a shorter spacing.
USG Sheetrock Brand All Purpose Joint Compound, ready-mixed: submittal sheet J1969
The drywall calculator starts joint compound at about 10 gallons per 1,000 square feet of panels and a 4.5-gallon container, both from this USG sheet. Other compounds cover differently: USG’s J371 guide gives 9.0 gallons per 1,000 square feet for Plus 3.
USG Sheetrock Brand Paper Joint Tape: submittal sheet J1736
The drywall calculator starts joint tape at about 370 feet per 1,000 square feet of panels and a 250-foot roll; USG lists 75, 250 and 500-foot rolls.
USG Sheetrock Installation and Finishing Guide J371: fastener spacing
The screw count uses USG’s spacing for Type W screws: 12 inches on ceilings and 16 inches on walls, along each stud or joist a sheet crosses, counting both edges. The 16-inch stud spacing is an example; enter your framing.
Marvin: Best interior door size for your home
The door counters start at an 80-inch height and a 30-inch width (36 inches on the exterior paint calculator). Marvin gives 80 inches as the standard door height in rooms with 8-foot ceilings, lists 24, 28, 30, 32 and 36 inches as the most common interior door widths, and names 30 inches as the most common bedroom door width. Change the size to your own door.
Pella: Standard window sizes
The window counters start at 32 by 48 inches, which Pella lists as a standard size: 2 feet 8 inches wide by 4 feet tall. Windows vary widely, so measure yours for a closer answer.
GAF FeltBuster synthetic roofing felt: data sheet
The underlayment line uses the standard FeltBuster roll GAF lists: 48 in by 250 ft, 10 squares (1,000 sq ft) before laps.
GAF Pro-Start starter strip shingles: data sheet
The starter line runs along the eaves and rakes at about 120 linear feet a bundle, the coverage GAF gives for Pro-Start.
GAF Seal-A-Ridge ridge cap shingles: data sheet
The ridge-cap line uses 25 linear feet a bundle: GAF gives 4 bundles per 100 linear feet at a 6 2/3 in exposure.
GAF Timberline HDZ installation instructions
The nail count uses 4 nails a shingle, the standard pattern (6 in high-wind areas), times the shingles in a square from the shingle length and exposure.
International Residential Code 2021, R905.2.8.5 Drip edge
Drip edge is sold in 10-ft pieces and adjacent pieces lap at least 2 inches, so each covers 9 ft 10 in along the eaves and rakes.
International Residential Code 2021, R806.2 Minimum vent area
Open vent area of 1/150 of the attic floor, or 1/300 when 40 to 50 percent of it is high on the roof and the rest at the eaves (in climate zones 6 to 8, with a vapor retarder in the ceiling too).