Outdoor project guides

Project guides

The real-world planning process behind each calculator: what to measure, which depth to choose, where waste hides and what to confirm before ordering.

• How much gravel do I need?Three things decide the order: the area you are covering, the depth of the gravel layer, and how much extra to allow for waste. Area × depth ÷ 12 gives cubic feet, ÷ 27 gives cubic yards, and cubic yards × the material density gives an estimated tonnage. The gravel calculator runs all of those steps from your own measurements.
• How to calculate mulchMulch is calculated exactly like any other bulk material: bed area × depth ÷ 12 gives cubic feet, and cubic feet ÷ 27 gives cubic yards. What makes mulch different is that the depth range is narrow, the bag sizes are misleadingly small, and the material settles after it is spread. This guide covers all three.
• How much topsoil do I need?Topsoil is calculated from the area you are covering and the depth you are adding: area × depth ÷ 12 gives cubic feet, and ÷ 27 gives cubic yards. The work is in choosing the depth, because top-dressing a lawn, filling a raised bed and topping up a planting bed use three completely different numbers.
• How to calculate landscaping materialsAlmost every landscaping material is planned with the same three numbers: an area, a depth, and a waste allowance. Learn that workflow once and it covers gravel, mulch, soil, topsoil, sand, decorative rock and paver base — only the depth guidance and the purchase unit change.
• How to plan a gravel drivewayA gravel driveway is calculated layer by layer, because each layer is a different stone at a different depth with its own compaction behaviour. Measure the footprint once, then run base, middle and surface through the same calculation and add the results into one order.
• How to plan a fencePlanning a fence is mostly sequencing. Measure the run, decide where gates go, choose post spacing, decide height, then pick a fence type — because each of those decisions changes the material list. The post count in particular depends on corners, ends and gates rather than on length alone.
• How to calculate fence materialsA fence take-off is a list of every component, not a single number. This page works through one complete example — a 100 ft fence, 6 ft high, with one 4 ft gate — and explains what each line of the result means, why the post count is not length divided by spacing, and where the allowances come from.
• How to plan a paver patioA paver patio is a layered build-up, and the planning order follows it: shape and area first, then the paver module and joint, then base and bedding depths, then edge restraint. Get the order right and the material list falls out of the measurements; get it wrong and you buy pavers before realising the base is the bigger purchase.
• How to calculate paver materialsPaver material is four purchases, not one: the pavers, the compacted base, the bedding sand and the edge restraint. This page works through a 12 ft × 20 ft patio from the first measurement to a shopping list, using the same engine as the calculators so every figure can be reproduced.
• How to calculate concrete for a slabConcrete volume is length × width × thickness, converted into cubic yards and rounded up to what a supplier will actually deliver. The arithmetic is simple; the decisions around it — thickness, waste allowance, and whether the job is bagged or delivered — are where a slab project succeeds or fails.
• How to estimate deck materialsA deck material estimate runs on four inputs: the deck size, the board width and stock length, the joist spacing, and the direction the boards run. Everything else — board rows, joist count, rim material, fasteners — follows from those. What it does not do is decide whether the deck is safe to build, which is a separate question with a separate answer.
• Outdoor project cost planningA useful outdoor project budget is built in two halves: quantities you calculate, and prices you enter from real quotes. This page covers both — which cost categories a project actually contains, why online estimates vary so widely, and how to turn a set of calculator results into a shopping list with a running total.

Material guides

What each material is, what changes its quantity, how it is usually sold and which calculator plans it.

• Gravel: sizes, uses and how to plan quantitiesGravel is a broad word covering crushed stone of many sizes and gradations, and the differences are not cosmetic: a stone that makes a good driveway base is a poor decorative cover, and the reverse. This page explains what changes between products, how to plan a quantity, and what to ask for at the counter.
• Pea gravel: uses, coverage and depthPea gravel is small, rounded stone, usually around 3/8 in. Its rounded shape is why it feels good underfoot and why it will not lock together: it shifts, it migrates, and it needs edging to stay where you put it. Plan it as a decorative surface rather than a structural layer.
• Mulch: categories, depth and coverageMulch is a category rather than a single product: bark, wood, and other organic materials are sold under the same word and behave differently. What they share is how they are planned — by volume, at a depth measured in inches — and that is what this page covers.
• Topsoil, garden soil and compost comparedThese three words are used loosely, and sometimes interchangeably, which is why so many soil projects go wrong before anyone measures anything. The distinction that matters is what each product is intended to do: add mineral growing depth, provide a ready-to-plant blend, or improve what is already there.
• Sand: common outdoor uses and how to plan a quantitySand is sold under many names, and they are not the same product. Bedding sand for pavers, leveling sand, masonry sand and play sand have different gradings and different intended uses. Choosing the right one is a supplier conversation; planning the quantity is arithmetic.
• Paver base: purpose, depth and compactionPaver base is the compactable aggregate layer under a paved surface. It spreads load, keeps the surface from settling unevenly, and provides the level platform the bedding layer is screeded onto. It is the layer that decides whether a patio stays flat, and it is usually the largest single quantity in the project.
• Concrete: ready-mix, bagged and how to plan a volumeConcrete is ordered by volume and specified by mix. The volume is arithmetic: length × width × thickness, or a cylinder for post holes. The specification — strength, air content, reinforcement, subgrade and curing — is a design decision that a quantity calculator cannot make for you.
• Fence materials compared for planningFence materials fill the same line in different ways. What changes between them is mostly how the infill is counted, how much maintenance the surface needs, and how the system handles posts, gates and hardware. This page compares them for planning purposes rather than recommending one.
• Decking materials compared for planningDecking materials differ in how they are made, how they behave outdoors, and what the framing beneath them has to do. The planning consequences are concrete: board width and stock length drive the count, joist spacing is often set by the decking product, and waste behaves differently. What this page will not do is declare a winner.

Cost guides

What actually moves the price of a job — and why two quotes for the same quantity differ. Every price in these guides is yours to enter.

• What changes the price of gravelGravel has no universal price, and any single figure quoted as one is describing a different project. What can be explained honestly is what moves the number: the material, the quantity, how it arrives, and how hard it is to get it where it needs to be.
• Mulch cost: bagged versus bulkMulch is one of the few materials where the packaging decision changes the cost more than the product choice. Bagged mulch carries a large premium per cubic foot, and bulk mulch carries a delivery minimum. This page explains where the crossover falls for your own project.
• What a fence estimate is made ofA fence estimate is a component list with prices attached. Understanding the components is what makes quotes comparable, because two installers can quote very different totals for the same boundary simply by including different things. This page breaks the list down, and the Fence Cost Calculator applies your own prices to it.
• What drives paver patio costA paver patio quote is a build-up, not a single material. Pavers are the visible cost, but the compacted base is usually the largest volume and the preparation is often the largest labour item. Understanding the layers is what makes two quotes comparable.
• What drives gravel driveway costA gravel driveway price has very little to do with the stone on the surface. Excavation, subgrade preparation, the base layers, drainage and delivery are usually where the money goes — and where two quotes for the same driveway can legitimately differ by a large margin.
• What drives deck costDeck cost is usually framed around the decking boards because that is the part you see. In practice the framing, footings, fixings and labour are often the larger share, and the surface is the smallest of the visible decisions. This page explains the structure of a deck price and where it can move.
• Landscaping project cost: the full breakdownA landscaping budget is a list of categories, and most overruns come from the categories that were never on the list. This page covers all of them: material, delivery, labour, equipment, preparation, waste and complexity — and explains how to build the number yourself rather than borrowing someone else’s average.

Where to start

If you have measurements in hand, open a calculator and add its result to Project Mode — the guides are there for the judgement calls the calculator cannot make for you.