The cost of a new patio

A new patio usually starts with a few quotes from landscapers. Two quotes for the same space can look very different.

Several choices shape the price. Some sit on the surface, and some sit underneath it where nobody sees them.

The surface you choose

The surface is the part everyone looks at, and its cost varies a great deal. The Royal Horticultural Society says gravel is by far the cheapest of the surfaces that let water through. Government guidance describes loose gravel as cheap and simple to lay.

Hard surfaces that let water soak in, such as permeable block paving or porous asphalt, can cost more than other options. They also need a contractor who knows how to build them. Government guidance says porous asphalt should be laid by a specialist company.

The layers underneath

Under the surface sits a sub-base. It is a layer of compacted gravel that spreads the load, so the soil below is not overstressed. Its depth sets how much digging the patio needs.

A conventional sub-base uses a stone mix with fine material in it, often called Type 1. A permeable surface needs an open-graded stone instead, such as Type 3 or 4/20, with gaps that let water pass and store it. Ask each landscaper which one they have priced, and how deep.

Where the rainwater goes

Rain that runs off a patio has to go somewhere. Builders can send it onto a lawn or border, into a soakaway, or into a rain garden. A rain garden is a planted dip that holds the water while it soaks away. Rain gardens and soakaways need deeper digging and more space, which adds to the work.

A patio laid against the house needs care at the wall. Government guidance on new walls puts the damp-proof course at least 150mm above ground level. Ask how the finished surface will sit below it.

Paving a front garden

The rules are different at the front of the house. In England, you do not need planning permission if the new surface lets water through, or if the rainwater runs to a lawn or border. Covering more than five square metres with a surface that does neither needs planning permission.

The RHS says Scotland has similar rules, which apply to paving of any size. In Wales, a new or replacement front surface must use permeable or porous materials, with an allowance for repairs of up to five square metres.

Cutting slabs safely

Slabs are often cut to fit edges and corners. The Health and Safety Executive says cutting paving, blocks or kerbs with a cut-off saw can produce very high levels of silica dust. Breathing that dust over time can cause lung cancer and other diseases.

HSE expects the saw to have a water attachment or dust extraction, along with a suitable mask. It is fair to ask a landscaper how they will cut the paving for your patio.

Comparing quotes

Citizens Advice suggests getting written quotes from at least three traders. A quote is a fixed price, and an estimate is a rough guess. Get a written contract before work starts, and pay in stages where you can. If a deposit is needed, Citizens Advice suggests keeping it under 25 per cent of the total.

A good quote names the area, the surface, the sub-base, the drainage and the removal of spoil. Each of those lines is something you can compare.