Patio Slab Calculator – Quickly and Easily Calculate How Many Slabs You’ll Need For Your New Patio

FAQs For Our Paving Calculator

How Many Extra Patio Slabs Should I Order To Take Into Account Wastage and Damages?

Our paving calculator assumes a wastage/breakage of 10% which is the industry norm, for circular patios or DIYers with little experience, you may wish to order extra patio slabs.

How Wide Should the Mortar Width Be?

There is no industry standard but the larger the slab size, the larger mortar width can be, if you wish. For slabs over 650mm we recommend a mortar width of 20mm, for anything less, either a butt joint with no mortar or a joint of 10mm.

How Can I Calculate the Square Metres in a Circle?

Measure the radius (centre to edge or half of the diameter) and then square this. So a 6cm radius squared is 36cm. Now multiply 36 by 3.14. The answer is 113.04cm² or 0.011304 square metres.

Do I Need to Seal My Patio Slabs After They’re Laid?

Sealing patio slabs can protect them from stains including oil, mould, moss, dirt and pollution. Weeds and grasses are also less likely to grow through a sealed slab and mortar joint.

This patio and paving calculator was created by and was last updated in August 2019.

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Author - Danny Woodley