Driveway Cost Calculator

Key Takeaways

• A new driveway needs a compacted sub-base of MOT Type 1, 150mm deep on firm ground and 200mm on soft ground, with a membrane under it. Put in your length and width, pick gravel, self-binding gravel, block paving or a resin bound kit, and the calculator lists every layer with its quantity and price.
• A domestic driveway sits on 150mm of compacted MOT Type 1 on firm ground and 200mm on soft or clay ground. MOT Type 1 is spread about 1.3 times deeper than it ends up, so 150mm compacted starts as roughly 195mm loose.
• Loose driveway gravel is laid at about twice the stone size, so 20mm gravel goes down 40mm deep and 10mm gravel 20mm deep. Gravel laid deeper than that lets tyres sink and turns the drive into a beach.
• A driveway membrane goes on the dug-out ground, under the sub-base, on every new drive. It is laid with 300mm overlaps and a peg every 1,000mm along the edges and joins, and it keeps the stone out of the wet British soil.
• Self-binding gravel on a driveway is laid 100mm deep in two layers of 50mm, straight onto the compacted MOT Type 1 with nothing between. It is spread about 1.5 times its finished depth and rolled down.
• A dig for a gravel driveway on firm ground goes about 190mm below the finished level, plus around 50mm where turf and roots come off first. Self-binding gravel needs about 250mm and block paving about 240mm.

I got asked "how much will my drive cost?" more than almost anything else when I was laying these for a living, and the answer people wanted was always the surface. The gravel, the blocks, the resin. The surface is the cheap, easy bit. Most of the stone and most of the digging sits underneath, in a layer nobody ever sees once the job is done. Outdoor Aggregates' calculator is built the other way round: base first, surface last, every layer counted.

How Does the Driveway Cost Calculator Work It Out?

The driveway cost calculator works the drive out layer by layer, from the bottom of the dig up, and prices each layer on its own. Area first, then depth, then the bags or units each layer needs.

1. The area comes from your shape: a rectangle, a circle, a triangle or an L shape, in metres or feet.
2. The sub-base is MOT Type 1 at 150mm compacted on firm ground or 200mm on soft ground, spread 1.3 times deeper loose, at 1,490kg per m³ loose.
3. The membrane is worked out in 1m strips with a 300mm overlap, then rounded to whole 14m rolls, with pegs every 1,000mm.
4. The surface depends on the drive: loose gravel at twice the stone size, self-binding gravel at 100mm, block paving on a 40mm sharp sand bed, or a resin bound kit laid 18mm deep over existing concrete or tarmac.
5. The edging is the outside edge, less any length already held by a wall, a kerb or the house.
6. One allowance, from 0 to 15%, goes on every quantity except the membrane and pegs, which come from the layout itself. It starts on 10%.

Everything Outdoor Aggregates sells shows the live shop price and the number of bags. Anything we do not stock yet (blocks, sand, resin bound kits and edging) shows a typical UK price range instead, so the total covers the whole drive. "Click to share this answer" copies a link that reopens the calculator with your figures in, and "Save as PDF" prints the list to take to a merchant or an installer.

How Deep Should Driveway Gravel Be?

Driveway gravel should be laid about twice the size of the stone, so 40mm of 20mm gravel and 20mm of 10mm gravel. Any deeper and the stones roll over each other under a tyre instead of locking together. I know nearly every gravel calculator on page one lays driveway gravel at 50 to 100mm, and I'd genuinely advise against it. The depth that holds a car is the sub-base. The gravel is a wearing coat on top, and a thin coat of angular stone on a hard base drives like a road. A thick coat drives like a beach.

Worked at 1,490kg per m³, before the allowance.

20mm is the size I recommend for a drive. It locks well, it does not follow you into the house, and it shrugs off a turning tyre better than the smaller grades. Slate is the odd one out: flat pieces need more depth to cover, so the calculator lays 20mm slate at 50mm, and I have written up why slate struggles under a car before you choose it. The calculator lists every stone in our driveway gravel range.

How Much MOT Type 1 Do I Need for a Driveway?

A driveway needs about one 850kg bulk bag of MOT Type 1 for every 2.9m² on firm ground at 150mm compacted, and one for every 2.2m² on soft ground at 200mm. That is before the allowance.

Outdoor Aggregates measured its own MOT Type 1 bulk bag at 850kg and 0.57m³ loose, which is where the 1,490kg per m³ comes from. A lot of tools online use a compacted density of 2.1 to 2.3 tonnes per m³ and then add 20% on top, which is why they come out a tonne or more heavier for the same drive. The 1.3 goes on the depth and the volume, never on the weight, because stone does not get heavier when you squash it.

Build it in layers of 150mm or less, and compact each one with a plate compactor before the next goes on. On soft ground that means two layers. I always did eight passes or more on each, and if the plate was still leaving a mark, it got more. The calculator's "Take me there" button opens MOT Type 1 with your measurements already filled in.

How Deep Do I Dig for a Driveway?

A driveway is dug to the sub-base depth plus everything that sits on top of it, so a 20mm gravel drive on firm ground goes about 190mm down. Allow about 50mm more where turf and roots come off first.

The calculator also gives the soil to dig out, in m³. That is the figure in the ground. Dug soil takes up more room once it is loose in a skip or a grab lorry, so ask the hire firm to size the muck-away from it. Digging, skips and plant hire are not in the calculator's total.

Does a Gravel Driveway Need a Membrane?

A gravel driveway always needs a membrane, laid on the dug-out ground under the MOT Type 1, never up under the gravel. Its job on a drive is to keep the sub-base and the soil apart, so the stone does not slowly sink into the mud.

I would put one under every drive. UK ground is wet for most of the year, and wet soil pumps up into a sub-base under the weight of a car, firm ground or not. Lay it in 1m strips along the length with a 300mm overlap, and peg every 1,000mm along the edges and the joins. The calculator counts the strips, the run and the 14m rolls of our heavy duty weed membrane, and the membrane pegs in packs of 25, 50 or 100.

The weeds people worry about on a gravel drive mostly blow in and root in the dust on top. A sheet under the sub-base does nothing about those, and a sheet just under the gravel tears and lifts within a season. A rake and a hoe over the summer do the job.

Loose Gravel or Self-Binding Gravel for a Driveway?

Self-binding gravel makes a firmer, tidier driveway than loose gravel, because its fines bind together into a solid surface that does not get kicked about or carried into the car. It costs more stone and more labour to lay.

Golconda Self Binding Gravel is the grade the calculator uses for drives. It goes down 100mm finished, in two layers of 50mm, each spread about 75mm loose and rolled. One 850kg bulk bag covers about 4.25m² of drive at that depth before the allowance. It sits straight on the compacted MOT Type 1 with nothing in between, so it binds to the base.

Two things to know before you choose it. Self-binding gravel takes about a week to set in summer and two weeks or more in a cold, wet winter, with gentle use for about three months after. And the steepest slope it holds is about 1 in 15. On anything steeper, the fines wash downhill in the first storm.

Loose gravel is quicker, cheaper and much more forgiving to lay yourself. It moves, though, it needs raking back, and it needs an edge to keep it in. Different drives, different answers.

Block Paving and Resin Bound Driveways

Block paving sits on a compacted sub-base like a gravel drive, while a resin bound kit goes over an existing hard base, and the calculator works out both. We do not sell blocks, sand or resin bound kits yet, so those rows show a typical UK price range.

Block paving at 200 x 100mm takes 50 blocks per m². They are laid on 40mm of sharp sand (sharp sand, never soft building sand, which squeezes out under a tyre), and the joints are filled with kiln dried sand, about one 25kg bag for every 3m². The allowance covers the cut blocks. Block paving always needs a fixed edge, bedded and haunched in concrete (a sloping shoulder of concrete behind the edge block), or the whole lot slowly spreads.

A resin bound kit is the DIY route, and it is laid over what is already there. It goes 18mm deep on a drive, over existing concrete or tarmac that is sound, with no cracks or movement. A 100kg kit (four 25kg bags of stone and the two tins of resin) covers about 3.55m² at that depth, so the calculator counts whole kits. There is no sub-base, no membrane and no digging, but it still needs a fixed edge or an existing kerb or wall to finish against. Our resin bound gravel kits guide covers what is in the box and how to lay it.

Worked Example: A 5m by 4m Gravel Driveway

A 5m by 4m gravel driveway on firm ground, with a membrane and a 10% allowance, takes eight bulk bags of MOT Type 1, two bulk bags of 20mm gravel, three rolls of membrane and 43 pegs. Here is how each figure is reached.

Delivery, digging, a skip, plant hire and labour are on top. If one side of the drive runs along the house or an existing kerb, put that length in the calculator's "Edge already held by existing wall or edge" box and the edging comes down.

What Does a Driveway Cost in the UK?

A driveway's cost in the UK splits into two very different numbers: the materials, which this calculator lists layer by layer, and the installed price, which adds the digging, the muck-away, the plant hire and the labour.

Most of the driveway cost calculators on page one are run by installers. They give an installed price per m², and plenty of them want your phone number before they show it. That is a fair number to have, but it tells you nothing about what is in the ground. The calculator here does the opposite job: every bag, every layer, priced, so you can either build it yourself or check that a quote has the depth in it. For a rough sense of order on a new drive, on materials alone:

1. Loose gravel is the cheapest new drive, because it is sub-base, gravel and an edge, with the shallowest dig.
2. Self-binding gravel costs more stone than loose, because the surface is 100mm deep instead of 40mm.
3. Block paving adds the blocks, a sand bed, jointing sand and a concrete-haunched edge.

A resin bound kit sits outside that list. It skips the sub-base and the dig altogether, but it only works where a sound concrete or tarmac base is already in place. If a quote seems cheap, ask what depth of sub-base is in it. That is where corners get cut, because nobody sees it until the ruts start.

Next Steps

Put your drive's measurements into the calculator above, pick the surface, and tap "Add to basket" or "Take me there" on anything we sell. "Take me there" opens the product page with your measurements already in its calculator. Click "Click to share this answer" to send the full list to whoever is helping you, or "Save as PDF" to keep a copy.

We stock MOT Type 1, the full driveway gravel range, Golconda Self Binding Gravel, membrane and pegs, all delivered in bulk bags to the kerb. If your drive needs more than a handful of bulk bags, call us, we can price a very competitive loose load at that size. Talk to the team on 0330 043 7585, 7am to 7pm.

Have you ever laid a driveway yourself, and which surface did you choose? Tell us in the comments how deep you took the sub-base and how it has held up, we would love to hear.

FAQs

Should I use 10mm or 20mm gravel for my driveway?

Driveway gravel at 20mm is the better size, because the bigger angular stones lock together under a tyre and are less likely to get carried into the house. 10mm works on a drive if it is laid thin, at about 20mm, but it moves more under turning wheels.

Is it better to buy driveway gravel in bulk bags or 20kg bags?

Driveway gravel is far cheaper in 850kg bulk bags than in 20kg bags for anything bigger than a few square metres. One bulk bag of 20mm covers about 14m² at 40mm, which would take more than 40 small bags.

Can I use gravel instead of MOT Type 1 under a driveway?

Decorative gravel cannot replace MOT Type 1 under a driveway, because clean stone has no fines to fill the gaps and it never compacts into a solid layer. MOT Type 1 is a graded mix of crushed stone and fines, made to lock hard under a plate compactor.

How do I stop gravel spreading off my driveway?

Gravel on a driveway spreads when it is laid too deep or has no edge to hold it. Keep the gravel at about twice the stone size, use angular stone rather than rounded pea shingle, and fix an edging on every open side with its top just above the gravel.

Is self-binding gravel good for a driveway?

Self-binding gravel makes a good driveway when it is the right grade and laid 100mm deep on a compacted sub-base. Golconda is the grade the calculator uses for drives, and it needs about a week to set before you drive on it gently.

Can I lay a gravel driveway on a slope?

A loose gravel driveway on a slope creeps downhill under tyres and in heavy rain, so it needs holding in place. Self-binding gravel holds up to about 1 in 15. I cover grids and drainage on slopes in my gravel driveway how-to.

Is a gravel driveway cheaper than paving?

A gravel driveway is cheaper than block paving on materials and labour, because it has fewer layers, a shallower dig and no sand bed or haunched edge. Switch the calculator between gravel and block paving with the same measurements and the gap shows straight away.

How much MOT Type 1 and gravel for a 30m² driveway?

A 30m² gravel driveway on firm ground takes about 9.6 tonnes of MOT Type 1 and about 2 tonnes of 20mm gravel with a 10% allowance. That is twelve 850kg bulk bags of sub-base, £1,368, and three of gravel, £426. The membrane depends on the shape, so put the length and width in the calculator.