Construction

Every calculator here does the arithmetic contractors run on the tailgate: how much material, what it costs, and what the code table says. Each tool shows its formula and its assumptions, so you can check the number before you price a job on it.

Estimating and materials
Start with the construction cost estimator for whole-project numbers, then get exact quantities: concrete for fence posts, gravel for a driveway, blown-in insulation depth and bags, and drywall mud and tape coverage.

Roofing
The roofing calculator with waste factor sizes the order including cuts and ridge loss. The metal roofing screw calculator counts fasteners per square so you buy screws once, not twice.

Structure and conversions
The joist span calculator references the standard residential span tables for floors and ceilings. The mezzanine floor calculator covers platform layout and cost, and the loft and attic conversion cost calculator prices the full conversion.

UK building rules
For UK jobs, the permitted development calculator checks whether an extension or outbuilding needs planning permission.

Pricing the work
Quantities are half the job; the price is the other half. Set it with the contractor markup calculator and track it with the job costing calculator. Before you quote, read the five construction pricing mistakes that lose money.