Project Guides | BuildCalc

Calculators give you a number. These guides show you why.

Use them to understand measurements, check assumptions and avoid common ordering mistakes before using the related calculator.

Concrete Quantity GuideHow to estimate concrete for slabs, footings, post holes and bagged mixes, with formulas, waste allowances and worked examples Fencing Materials GuideEstimate fence panels or pickets, posts, rails and post concrete without overlooking corners, gates, spacing or waste Decking Materials & Fastener GuideCalculate deck boards, joists and fasteners from board width, gaps, support spacing and practical waste Brick & Block Quantity GuideEstimate masonry units and mortar from net wall area while accounting for openings, unit size, joints and waste Plasterboard & Drywall Quantity GuideEstimate sheets, joint compound and related materials for walls and ceilings, with regional sheet-size guidance Roofing Materials Calculation GuideUnderstand roof area, pitch, tile or shingle quantities, underlay and guttering before ordering Flooring Quantity & Waste GuideEstimate flooring packs and underlay while allowing for room shape, pattern, cuts and pack coverage Wall & Floor Tiling Quantity GuideCalculate tiles, adhesive and waste using surface area, tile size, layout and product coverage Paint Coverage & Quantity GuideEstimate litres or gallons from paintable area, number of coats and the coverage stated for the chosen product Wallpaper Rolls & Pattern Repeat GuideEstimate wallpaper rolls correctly by using drops, roll length and pattern repeat rather than wall area alone Insulation Quantity GuideEstimate insulation rolls, batts or boards from net area and product coverage while checking application requirements Paving & Patio Materials GuideEstimate paving units, sub-base and bedding materials for patios and paths using layer depth and coverage Gravel, Soil, Sand & Aggregate GuideConvert area and depth into bulk volume and practical order quantities for landscaping and groundwork Timber & Lumber Quantity and Dimensions GuidePlan timber lengths, stud spacing and material volume while avoiding nominal-versus-actual dimension mistakes Construction Waste Allowances ExplainedHow to choose realistic material waste and contingency percentages instead of applying one number to every project Driveway Materials GuideEstimate excavation, sub-base, gravel, asphalt or concrete quantities from area and layer depth Drainage Fall & Gradient GuideUnderstand fall, gradient and level difference calculations for drainage and site setting-out

How the guides are written

Each guide is built around the same transparent approach as our calculators: define the measurement, show the mathematical relationship, distinguish theoretical quantity from practical purchase quantity, and identify where product data or site conditions override a generic estimate.

For the underlying rules used throughout the site, read our calculation methodology.