Landscaping and garden calculators — turf, topsoil, decking and fencing

Calculators in this cluster

Turf calculatorRolls of turf and topsoil for a new lawn.
Topsoil calculatorTonnes of screened topsoil for beds, borders and a new lawn.
Decking calculatorBoards, joists, screws and joist hangers for a timber deck.
Fence calculatorPanels, posts, gravel boards and bags of postcrete.

What this cluster is for

Four calculators that share a soil-and-timber logic. Turf and topsoil are about what a plant grows in; decking and fencing are about timber quantities, fixing centres, and what has to be buried.

The recurring mistake across all four is treating an area as the answer. Turf is sold in rolls and needs a cutting allowance; topsoil is sold by the tonne and settles after it is watered; decking is bought per board and computed from joist centres rather than from area; a fence is computed per bay from post centres. Each calculator converts the measurement you can take into the unit the merchant actually sells.

What usually goes wrong

Buying topsoil with no specification. BS 3882 is what defines topsoil. "Topsoil" on a bulk bag is not a specification, and subsoil sold as topsoil will not grow a lawn.
Laying turf on the ground as found. Turf roots into what is beneath it. Compacted or poor subsoil shows up as yellow patches within a season.
Treating the topsoil volume as the finished depth. Screened topsoil settles once it is watered and walked on — typically by around a tenth. Order for the settled depth.
A deck with no airflow under it. A deck needs ventilation beneath and a slight fall. Boards tight against damp ground rot from the underside outwards.
Fence posts too shallow, or dry-packed. Posts need to sit below the depth the panel’s leverage reaches and be concreted. A post that moves takes the whole panel with it.
Boundary rules ignored. Fences and raised platforms can be permitted development up to a point, and the limits are not the same on every side of a property.

What to order together

Screened topsoil, turf, and a starter fertiliser
Decking boards, joists, joist hangers, and coated or stainless screws
Fence panels, posts, gravel boards, and bags of postcrete
Hire: a turf cutter for the old lawn, and a post-hole auger for a long fence run

Related clusters

Cross-links here are contextual, not a second home: each calculator belongs to exactly one cluster above.

All 13 calculators

Plasterboard calculatorSheets, screws and scrim tape for walls and ceilings.
Paint calculatorLitres and tin sizes for walls and ceilings.
Turf calculatorRolls of turf and topsoil for a new lawn. In this cluster.
Paving calculatorSlabs, MOT Type 1 sub-base and sharp sand bedding.
Concrete calculatorCubic metres, plus cement, sand and aggregate by the bag, or ready-mix.
Gravel calculatorTonnes of decorative gravel, or MOT Type 1 sub-base, in bulk or 25 kg bags.
Topsoil calculatorTonnes of screened topsoil for beds, borders and a new lawn. In this cluster.
Decking calculatorBoards, joists, screws and joist hangers for a timber deck. In this cluster.
Fence calculatorPanels, posts, gravel boards and bags of postcrete. In this cluster.
Flooring calculatorPacks of flooring, underlay and scotia or beading.
Brick calculatorBricks, blocks, mortar, sand and cement for a wall.
Kitchen worktop calculatorWorktop lengths in 600, 620 or 900 mm, mitres, upstands and cost.
Carpet and rug calculatorCarpet off a 4 m or 5 m roll, plus the rug size that fits.
All calculatorsBack to the homepage.