Calculators in this cluster
What this cluster is for
Seven calculators that share a soil-and-timber logic. Turf, topsoil, gravel and paving are about what goes on the ground and what holds it there; decking, fencing and a shed base are about timber and concrete quantities, fixing centres, and what has to be buried.
The recurring mistake across all seven 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
- MOT Type 1 sub-base for a shed base or under paving, and weed membrane under gravel
- Paving slabs, sharp sand bedding, and an edge restraint for the open sides
- Hire: a turf cutter for the old lawn, and a post-hole auger for a long fence run
Plan your garden
Start here if you are planning rather than buying: measure the space, decide what goes where, and let the calculators turn each part into a quantity. The layout templates are the shapes real gardens have; the plans below are whole jobs.
Garden plans and projects
Each plan below is a whole job: a drawing, the order to do it in, what people forget, and a material take-off worked out by the calculator that sizes that material. One button adds the whole list to your project.
Related clusters
Cross-links here are contextual, not a second home: each calculator belongs to exactly one cluster above.