Accurate material quantities for every outdoor project. From fencing, decking, and paving to mulch, gravel, and garden walls - calculate what you need before you order and make sure your project runs smoothly from start to finish.
External landscaping projects involve materials that are sold by the tonne, the metre, the panel, or the bag - and the unit conversions between areas, volumes, and weights catch many buyers out. Ordering too little means a second delivery charge and possible delays; ordering too much leaves you with surplus material to store or dispose of.
Our landscaping calculators handle all the unit conversions for you. Whether you need paving slabs in square metres, fencing in linear metres, or bark chip in m3 and tonnes, the calculators give you the right output for the material you are ordering.
From professional landscapers and groundworkers to homeowners improving their garden, these tools make material planning quick and reliable.
Select a calculator below to get instant material quantities for your outdoor project.
Calculate posts, rails, boards, panels, and fixings for any style of garden fencing. Enter the total fence run length, panel width, and post spacing. Supports close-board fencing, hit and miss, panel fencing, and palisade styles. Returns number of posts, post concrete quantities, rails, boards or panels, and fixing counts with optional cost estimate.
Use CalculatorEstimate paving slab quantities, block paving units, or decking board and joist requirements for patios, paths, driveways, and outdoor living areas. Enter the area dimensions, select the paving or decking type, and specify joint width or board gap. Returns total quantities, sub-base requirements, and sand bedding volumes.
Use CalculatorCalculate the volume of mulch, bark chip, wood chip, or decorative gravel needed to cover garden beds, borders, paths, and play areas. Enter the area and desired application depth. Returns volume in litres and m3, weight in kg for comparison with bagged products, and the equivalent number of standard bags or bulk bags required.
Use CalculatorEstimate gravel stabilisation grid or cellular confinement system panel quantities and infill gravel volumes for permeable driveways, paths, and parking areas. Enter the area to be covered, select the panel size and cell depth, and get the number of grid panels, infill gravel volume in m3 and tonnes, and sub-base material requirements.
Use CalculatorCalculate the sub-base depth, aggregate tonnage, and attenuation volume for SuDS-compliant permeable driveways and paved areas. Select your design rainfall event, sub-base material, and intended use - the calculator works out both the structural and attenuation requirements and gives you the governing depth to order.
Use CalculatorCalculate bricks or blocks, mortar, and coping stones for garden boundary walls, raised bed retaining walls, and low dividing walls. Enter wall length, height, and thickness, choose your brick or block size, and set the mortar joint width. Returns brick and block counts, mortar volumes, and optional coping stone quantities.
Use CalculatorBefore you build, make sure your project has the right consents in place.
Find out whether your project needs full planning permission or qualifies as Permitted Development. Covers extensions, outbuildings, loft conversions, fencing and more - with clear rules for England.
Explore planning guidesPlain-English guidance on all Parts of the Building Regulations - from Part A (structure) and Part B (fire safety) to Part L (energy efficiency). Know what Building Control will be checking before work begins.
Explore building regsWorking on a listed building? Most works - inside and out - require Listed Building Consent. Our guides cover the consent process, acceptable materials, enforcement risks, and how to find a heritage consultant.
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