--- title: "Room Measurement Calculator for New Zealand: m² and Volume | AumnI tools" description: "Work out floor, wall, skirting and volume figures for New Zealand rooms in metres, then convert area into boxes of flooring or panels with a waste allowance." url: https://aumnitools.com/nz/tool/room-measurement-calculator category: "Lifestyle" country: "New Zealand" updated: 2026-11-08 --- # Room Measurement Calculator A New Zealand renovation quote begins with room sizes in metres and a clear idea of how much floor, wall and skirting is involved. This version opens in metres and square metres, takes doors and windows off the walls, and converts the area you choose into boxes using your own waste and coverage figures. ## New Zealand rules and figures - New Zealand building plans and flooring suppliers work in square metres, so the page starts in metres and m². - GST of 15% is included in New Zealand shelf prices, so enter a box price exactly as marked. - A box starts at a cover of 2 m² with 10% waste, example figures to be replaced by the label on the pack. - Switching Display units to feet converts every typed size, then shows square feet and cubic feet. Sources: [Inland Revenue: New Zealand tax authority (GST rate)](https://www.ird.govt.nz) (checked 2026-11-08) ## How the Room Measurement Calculator works The calculator keeps each room as a flat-ceilinged rectangle. Everything you type in metres is converted to feet for the sums and back again for display, so totals are exact to the number typed. Formula: `volume = L × W × H; net wall = perimeter × H − openings; order = ceil(area × (1 + waste) ÷ cover per box)` - The starting rooms are a 5.5 × 4.3 m living room and a 3.7 × 3.4 m bedroom with 2.7 m ceilings, each with a door and windows already added. - Opening areas ignore frames and reveals, and each size is typed as metres. - Waste starts at 10%, and the preset buttons switch it between 5, 10, 15 and 20%. A box starts at 2 m². - The price per box is left empty so the cost is zero until you enter it. ## How to use the Room Measurement Calculator 1. **Type the room sizes.** Enter length, width and ceiling height in metres, using Add room for each extra room, hallway or garage. 2. **Include windows and doors.** Use + Door and + Window to describe each opening so the wall figure is net. 3. **Compare the totals.** Open Totals for floor, wall, ceiling, volume and perimeter, then check each room in the table. 4. **Turn area into packs.** On Materials, choose floor or walls, set Waste allowance (%), the pack cover and Price per unit. 5. **Save the numbers.** Copy summary or Export CSV records the figures for the supplier. ## Example: A 3.7 × 3.4 m bedroom, planks with 10% waste The bedroom has 12.58 m² of floor and a 14.20 m perimeter. Its 2.7 m walls total 38.34 m² before the door and window, which take out 2.72 m², leaving 35.62 m² net. The volume is 33.97 m³. Planks with 10% waste need 13.84 m², so 7 boxes of 2 m² cover it, and 0.16 m² is left over. ## When to use the Room Measurement Calculator - **Re-carpeting a bedroom.** Enter the room and read floor area with an allowance for cuts before asking for quotes. - **Lining a garage.** Use the net wall figure to order sheets for a garage conversion and subtract the roller door as a large opening. - **Skirting run for a renovation.** Read the total perimeter, then take away doorways to estimate lengths of skirting. - **Insulation planning.** Use wall and ceiling area to compare batts or panels by pack coverage. ## What the Room Measurement Calculator does not do - Switching units converts the typed sizes (rounded to 4 decimals), so flipping back and forth can leave tiny rounding differences. Metric and feet-and-inches shorthand cannot be mixed: inch shorthand is read only in feet mode. - Rooms are rectangles with flat ceilings. For an L-shape, add two rooms; sloping ceilings need an average height. - The Materials tab prices whole units only, so the cost is units times the price you enter, with no discounts, tax or delivery. Outside the US no starting price is filled in. - Opening areas ignore frames and reveals, and every door or window you add uses a typed size, not a catalogue size. - Measure real rooms at several points: the tool trusts the one number you type for each side. ## When something else is a better fit - **When you are estimating paint and want coats, texture and colour change built in**, use the [Paint Calculator](https://aumnitools.com/tool/paint-calculator.md). - **When you need to convert measurements between feet, metres and inches**, use the [Unit Converter](https://aumnitools.com/tool/unit-converter.md). - **When the room is irregular or you need a scaled drawing**, use a floor-plan or CAD app, or a laser measure with a sketch. ## Questions about the Room Measurement Calculator ### How much floor is in a 3.7 by 3.4 metre bedroom? 12.58 m². With 10% waste that is 13.84 m², which takes 7 boxes of 2 m². The room’s perimeter is 14.20 m for skirting. ### How do I enter a room that is not a rectangle? Split it into rectangles and add each as its own room. An L-shaped lounge is two rooms, and the totals add them together. Sloping ceilings need an average height. ### Does the tool include GST? No tax is added. Cost is whole boxes times the price typed, and New Zealand shelf prices already include 15% GST, so the marked price is the right one to enter. ### What is net wall? It is the gross wall area minus the doors and windows you added. Use it for linings and panels. For paint, the gross figure is the safer base because cutting in costs paint. ### Can I change the box cover? Yes. The Coverage per unit box starts at 2 m² and takes any number, such as 2.4 m² for a pack of planks. The box count updates as you type. ## Related tools - [Paint Calculator](https://aumnitools.com/tool/paint-calculator.md): Cans of wall, ceiling, trim and primer paint, in gallons or litres - [Unit Converter](https://aumnitools.com/tool/unit-converter.md): Converts 102 units in 11 categories, with temperature offsets and 0 to 12 decimals - [Home Maintenance Reminder](https://aumnitools.com/tool/home-maintenance-reminder.md): 45 home jobs with set intervals; log last-done dates to see what is overdue ## About this page Runs in your browser: what you enter is processed on this device and is not uploaded. Last checked against the tool's code on 2026-11-08. Interactive version: https://aumnitools.com/nz/tool/room-measurement-calculator