I'm Valerii Zugravu, and I build and check these calculators myself. When something is wrong I fix it and say so here, with the date. If a result ever doesn't match what you see on site, use Report a problem under it. For how the calculators are checked, see how accurate are the calculators?
3 November 2026
- FixKitchen worktop calculator: the lengths and depths you can choose now match what UK merchants sell (2m, 2.4m, 3m, 4m and 4.1m; 600–635mm deep). The 3.6m length and 650mm depth were removed, because none of the merchants we checked sell them. See it
- NewNew guide: Kitchen Worktop Sizes UK. Standard UK worktop lengths, depths and thicknesses by material, which length to buy for your run, heights, corners and breakfast bars. See it
- NewHow accurate are the calculators? Eight results checked against published UK figures from Tarmac, Thistle, Marley, Dulux and Approved Document H. See it
- New"Was this result helpful?" under every result, so you can tell me which calculators need work. See it
- ImprovedSearch understands questions like "how much sand for render", plurals and small typos.
- ImprovedEach calculator's worked answer for its starting values is now part of the page itself, so it shows even where JavaScript doesn't run.
- ImprovedEight popular calculators (brick, plasterboard, fence, MOT Type 1, kitchen worktop, extension cost, radiator and square metre) now list what they assume: the rates, rounding and pack sizes behind the answer.
2 November 2026
- FixConcrete calculator: clearer wording. Mix ratios are parts by volume, and 1:6 is a nominal mix, not a strength class. See it
- NewConcrete calculator: optional steel reinforcement mesh (A142, A193 or A252), with sheets, laps, spacers and tie wire. See it
1 November 2026
- NewNew guide: How to Plaster a Room. Skim or undercoat, prep for each wall, mixing, the two-coat skim timeline, drying and a room planner with hand-checked UK prices. See it
28 October 2026
- FixQuote builder: unticking VAT on a quote that had already been sent no longer changes that quote's total. See it
- NewEmbeds for other websites: preset the bulk bag size, your own colour, and hide merchant prices. See it
27 October 2026
- FixFoundation advice now follows the Approved Document A rule (concrete at least as thick as it projects past the wall, minimum 150mm) instead of a rule of thumb. See it
- ImprovedQuick answers (bricks per m², bags of cement per m³ and 27 more) moved onto their calculator pages, next to the tool that works them out.
- ImprovedSources lists added to the brick, concrete, plaster, paint, roof tile and gutter calculators, with links you can check.
25 October 2026
- NewNew guide: How to Lay a Patio, Step by Step. Setting out, dig depth, sub-base, a full mortar bed, porcelain priming, jointing and a patio planner with hand-checked UK prices. See it
- NewNew guide: How Deep Should Foundations Be?. Foundation depths for walls and extensions on sand, clay and near trees, trench sizes, building control and a priced trench planner. See it
- ImprovedPages load much faster on phones, and every guide got diagrams, photos and at-a-glance figures.
24 October 2026
- FixEight calculators that mix sand, cement and ballast now share one method, so the same mix gives the same answer everywhere. Radiator room factors corrected.
- FixA full review found 13 problems, from the mixing water for plaster to swapped hip measurements on the roof calculator. All 13 were fixed the same day. See it
- ImprovedSkip weight limits, door widths on the skirting calculator, a gutter capacity check, whole-room mode on the plaster calculator and grab-lorry loads on the excavation calculator.
23 October 2026
- NewQuote builder for trades: turn a project into a priced quote and a PDF. See it
22 October 2026
- ImprovedNew look across the site, with the calculator next to its results.
19 October 2026
- ImprovedAll 41 calculators got fuller explanations, with a worked example that uses the calculator's own starting values.
18 October 2026
- NewNew guide: How to Build a Brick Garden Wall. Rules, footings, single vs double skin, step-by-step build and a costed shopping list with hand-checked UK merchant prices. See it
- NewNew guide: How to Insulate a Loft. Top up to 270mm yourself: is it worth it, the two-layer method, storage without squashing it, and a loft planner with hand-checked UK prices. See it
- NewNew guide: How to Build a Stud Wall. Split a room: rules, finding joists, framing, doorways, soundproofing, boarding and a stud wall planner with hand-checked UK prices. See it
- NewProject planners: enter your sizes once and get one shopping list for a whole job, such as a patio, a garden wall or a fence. See it
- NewBuild your own calculator for any material, worked out by coverage, count or weight. See it
- NewNew guide: How to Put Up a Fence & Fix Storm Damage. Fix a blown-down panel, who owns the fence, post depths, step-by-step install and a fence planner with hand-checked UK prices. See it
17 October 2026
- NewNew guide: Patio & Driveway Sub-Base Depth Guide. How deep to dig and how much MOT Type 1 for patios, paths, sheds and driveways. See it