Turf calculator: rolls for your lawn

How it works

Measure the lawn area in square metres. For several separate patches, add their areas together. If you have an irregular outline, divide it into simple shapes, calculate each area, then add the results. Exclude paths, patios and other surfaces that will not receive turf.

Turfco says irregular cuts may need a few extra square metres or about 5%, treat this as that supplier’s example, not a universal rule. Choose an extra turf allowance that reflects your own cuts and layout. The supplier source identifies the area in one Instant turf supplier roll example roll, but does not publish a universal allowance for trimming or waste. The calculator starts at 0%, which is an unadjusted baseline rather than a recommendation, and lets you enter your own percentage. It rounds the final order up to a whole roll.

The optional topsoil field estimates cubic metres from the same lawn area and a depth that you enter. Leave it blank if you do not need that estimate. The calculator does not suggest a topsoil depth, convert the volume to a supplier’s bag size, or include extra for settlement.

Formula

• Turf area to order = lawn area × (1 + extra allowance ÷ 100).

• Rolls to order = turf area to order ÷ 1 m² per roll, rounded up to a whole roll.

• Topsoil volume = lawn area × the depth you enter in metres. Convert a depth in millimetres to metres by dividing it by 1,000. The extra turf allowance does not change this topsoil estimate.

Worked example

1. 1

   For a 6 m × 4 m lawn, the area is 6 × 4 = 24 m². With 0% extra, order area is 24 × 1 = 24 m². The cited Instant turf supplier roll example example states 1 m² per roll, so 24 ÷ 1 = 24 rolls. Round up and order 24 rolls.

2. 2

   If you also enter 75 mm for topsoil, convert it to 0.075 m. The volume estimate is 24 × 0.075 = 1.8 m³. This is the volume at the depth you chose, not a depth recommendation.

Assumptions and limits

The Australian supplier source gives a product-specific example: Instant turf supplier roll example is listed as approximately 1.8 m × 0.585 m and 1 m² per roll. Other grass types, suppliers or order formats may differ. Check your chosen supplier’s current dimensions, minimum order, availability and delivery conditions before ordering.

The calculated roll quantity is an area estimate. It does not plan strip direction, joins, edge cuts, lawn shape, damaged pieces or how reusable offcuts fit another part of the lawn. Those details affect the extra you need, so measure carefully and choose an allowance suited to your own layout.

The optional topsoil output is volume only. The calculator does not recommend a depth. Soil can settle and site levels vary, the estimate does not account for compaction, uneven subsoil, edging, existing topsoil, drainage, soil type or how a supplier sells material. Confirm preparation and soil depth for your lawn with a local turf supplier or qualified landscaper.

Frequently asked questions