DIY Estimating Guides

Step-by-step explanations behind our calculators — how to measure, which allowances to add and how materials are sold in the US, UK, Canada and Australia. Every guide is written and maintained by the DIYCalcLab Editorial Team under our editorial policy.

Concrete

• How Much Concrete Do I Need? A Step-by-Step GuideWork out concrete volume for slabs, footings and post holes in cubic yards, cubic metres and bags — with worked examples, waste allowances and ordering tips.
• Bagged Concrete vs Ready-Mix: Which Should You Use?When to mix bags yourself and when to order a ready-mix truck — volume thresholds, labour, finish quality and the questions to ask a supplier.

Paint & Wallpaper

• How Much Paint Do I Need for a Room?Calculate wall area, deduct doors and windows, choose coverage and coats, and buy the right mix of gallons, quarts or litre tins — with US and UK examples.

Tile

• Tile Waste Factor Explained: How Many Extra Tiles to BuyWhy tile jobs need extra tiles, how layout, tile size and room shape change the waste factor, and how to turn area into boxes with spares.

Flooring

• How to Measure a Room for FlooringMeasure rectangular and irregular rooms for laminate, vinyl plank and hardwood, add the right waste factor and convert area to boxes — with diagrams in words and worked examples.

Roofing

• Roofing Squares Explained: From Footprint to BundlesWhat a roofing square is, how pitch changes roof area, how many bundles of shingles you need, and the extras — starter, ridge cap and underlayment.

Landscaping

• Mulch, Gravel and Topsoil: How Deep Should Each Layer Be?Recommended depths for mulch, decorative gravel, sub-base and topsoil, how much one cubic yard or cubic metre covers, and how to convert volume to bags and tons.

Decking

• How to Plan a Deck: Size, Layout and MaterialsPlan a deck from site to materials list: choosing size around board lengths, board direction, gaps, joist spacing, footings and the permits you may need.

Fencing

• Fence Planning Checklist: Before You Dig the First HoleA practical checklist for planning a wood or panel fence: boundaries, permits, layout, post spacing, gates, materials and concrete per post.

Drywall (Plasterboard)

• Drywall and Plasterboard Sheet Sizes: US vs UK vs AustraliaStandard drywall and plasterboard sheet sizes and thicknesses in the US, UK and Australia, how to choose a size, and how sheet size changes the number of joints.

Framing & Lumber

• Nominal vs Actual Lumber Sizes (and What It Means for Board Feet)Why a 2×4 is not 2 by 4 inches, a chart of nominal and actual lumber sizes, metric equivalents, and how sizes affect board-foot pricing.

Conversions

• Imperial vs Metric for DIY Projects: A Practical Conversion GuideThe length, area, volume and weight conversions that matter on DIY projects, common traps, and how product sizes differ between the US, UK and Australia.