Measure your project
Measure the finished patio footprint. Enter specified base and bedding thicknesses. Check cuts, edge restraints and drainage with your installer before ordering.
Measure the space you need to fill. Rectangles use length and width; circles use diameter. For several sections, choose combined areas and add rectangles, then subtract exclusions. The final area must be greater than zero.
Count the paving before pricing packs
Enter the finished patio footprint, matching rectangular slab dimensions, joint width and cutting allowance. The piece estimate uses slab-and-joint modules; it does not decide where cuts go. Enter supplier pack coverage to calculate full packs independently.
A hypothetical 4 m by 3 m patio with 600 mm square slabs, zero joint in the arithmetic and 10% cutting allowance gives 37 pieces. At 5 m² per pack, the same area and allowance require three packs. Zero joint is an arithmetic illustration; follow the actual product’s joint specification.
Specify the bedding before adding sand
Marshalls distinguishes mortar bedding from flexible sand bedding for different flags. The optional sharp-sand layer starts off excluded. Enable it only if the installation specification calls for a sand layer and enter that specified depth.
This planner does not calculate cement, mortar yield, jointing compound or edging. A patio requiring mortar needs those quantities checked separately. Type 1 remains its own line, with a compacted depth and supplier-confirmed loose-material allowance.
Use the unit you will pay for
Select full packs or individual slabs for the paving quote. Pack pricing needs coverage per pack; otherwise the calculator cannot price that order. A cutting allowance increases both the piece estimate and the area used for pack rounding.
Base and any sand layer have independent bag and loose-load comparisons. Slab transport is entered on the paving line. Allocate a delivery shared across materials once, and check pallet access, unloading and what the supplier means by quoted coverage.
Volume formula
Allowance applies once to each volume layer. No density or compaction factor is assumed. If buying by weight, enter the density for your supplier’s product in the units shown.
Sources & what they cover
- NIST SI conversion factorsNational Institute of Standards and Technology
Exact US customary and SI conversion factors; no material or installation recommendations.
Source checked - MOT Type 1 jumbo bagWickes
Named sub-base product and 800 kg bag. Bag weight can vary with moisture. No universal density or construction depth imported.
Source checked - Sharp sand jumbo bagWickes
Named sharp-sand product and 800 kg bag. No density, mortar recipe or bedding depth imported.
Source checked - Paving installation and delivery FAQsMarshalls
Different bedding systems for paving flags, joints, VAT and delivery access. No generic installation specification imported.
Source checked
We check what each reference covers. A source check does not mean a specialist has reviewed this tool. You supply the depths, densities, prices and blend proportions.