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Turf calculator

Work out how many rolls of turf you need for your lawn. It handles rectangles, circles and triangles, adds extra for cutting, and tells you the weight of the delivery. You can also work out the topsoil to put underneath.

Man laying rolls of turf on prepared soil in a back garden with staggered joints
%

5% for a plain rectangle, 10% for curves and awkward edges.

Your result

Rolls of turf

22

each roll is about 1 m², 0.61 m × 1.64 m

Turf to buy
22 m²20 m² of lawn plus 10% extra, rounded up to whole rolls
Lawn area
20 m²
Weight of the delivery
330–440 kg15–20 kg per roll
  • Order turf for the day you will lay it. Rolls are heavy, perishable and best laid straight away in spring and summer, or within 24 hours in autumn and winter.
  • Roll sizes vary between growers. Check the size on your supplier's listing and order by square metre.

Add this to your project shopping list, then print it or take it to the merchant.

Open shopping list

How to use the turf calculator

  1. Choose the Shape of the area. Pick a rectangle, circle or triangle, or enter the area if you already know it.
  2. Measure the lawn and enter the sizes. Each box has its own unit, so you can use metres or feet.
  3. Set Extra for cutting and waste. Use 5% for a plain rectangle and 10% for curves and awkward edges.
  4. Tick Also work out the topsoil underneath if you need to prepare bare ground.
  5. Read the number of rolls and the weight of the delivery. Then tap Add to shopping list or Share link to send it to your turf supplier.

Why use this calculator

It handles lawns that are not square. Circles and triangles are built in. For any other shape, split the lawn up, add the areas and enter the total.

It rounds to whole rolls. A standard UK turf roll is about 1 m², so the calculator tells you how many rolls to order and how many m² you are really buying.

It warns you about the weight. Turf is heavy, and you can see the total weight before the delivery arrives.

It works out the topsoil underneath as well, so you can order everything for the lawn together.

How we worked it out

Your numbers, step by step. This updates as you change the calculator.

  1. Area = length × width = 5 m × 4 m = 20 m²
  2. Add 10% for cuts: 20 m² × 1.1 = 22 m²
  3. Rolls = 22 m² ÷ 1 m² per roll = 22 rolls (a roll is about 0.61 m × 1.64 m)

The formula

Work out the area of the lawn in m², add the extra for cuts, and divide by the size of one roll.

Rolls = area × (1 + extra) ÷ 1 m², rounded up

A 5 m by 4 m lawn is 20 m². With 10% extra that is 22 m², so you need 22 rolls.

  • Circle: π × (diameter ÷ 2)².
  • Triangle: base × height ÷ 2.
  • Delivery weight: rolls × 15 to 20 kg.
  • Topsoil underneath (optional): area × 0.15 m × about 1.5 tonnes per m³. For 20 m² that is 3 m³, or 4.5 tonnes. The topsoil is not given an extra for settling here, so use the topsoil calculator if you want that.

What we assume

  • A standard roll is about 1 m². We use the Rolawn Medallion roll, which is 610 mm by 1,640 mm and 12.5 mm thick, and weighs 15 to 20 kg. We have not found other roll sizes confirmed, so check your supplier.
  • Extra of 5 to 10% for cuts is a rule of thumb, not a supplier figure.
  • Topsoil is 150 mm deep for bare ground, at about 1.5 tonnes per m³.

Tips

  • Order the turf for the day you will lay it. Rolls are heavy and perishable. Rolawn says to roll its turf out straight away in spring and summer, and within 24 hours in autumn and winter.
  • Prepare the ground first. Rake it level, remove stones and weeds, and add topsoil where needed. The topsoil calculator works out how much.
  • Measure an irregular lawn by splitting it into rectangles, circles and triangles. Work out each area, add them up, and use the "I already know the area" option. The square metre calculator can help.
  • Roll sizes vary between growers. Check the size on your supplier's listing and order by square metre rather than by the number of rolls.

FAQs

How many rolls of turf do I need for my garden?
Your lawn area in m² plus 5 to 10%, rounded up, since a standard roll is about 1 m². A 5 m by 4 m lawn is 20 m², so 21 rolls with 5% extra or 22 with 10%.
How big is a standard roll of turf in the UK?
About 1 m², which is around 610 mm wide and 1.64 m long, and about 12.5 mm thick. Other roll sizes exist, so check your supplier's listing and order by square metre.
How much extra turf should I order for cutting and waste?
5% for a plain rectangle and 10% for curves and awkward edges. The calculator uses 10% unless you change it.
How do I measure an irregular shaped lawn for turf?
Split it into rectangles, circles and triangles, work out each area, and add them up. Then pick "I already know the area" in the calculator and type in the total.
How much topsoil do I need under turf?
About 150 mm of topsoil on bare ground, which is 3 m³ or 4.5 tonnes for a 20 m² lawn. If the soil you have is decent, 100 mm may be enough.
How much does the turf delivery weigh?
A roll weighs 15 to 20 kg, so 22 rolls is 330 to 440 kg. For a 100 m² lawn with 10% extra, 110 rolls weigh about 1,650 to 2,200 kg.

Last reviewed: 6 November 2026 · How we calculate · Report an error