Laying tarmac and concrete accurately is skilled work, best left to a professional. But gravel and paving slabs are relatively easy to lay. For a path, choose the obvious route through the garden. If there is no obvious route, create one by using obstacles or barriers.
Put a paved area in a position of full sun, as far as possible. The area will be used more often and stay cleaner. A paved area must be situated so that it is private, or can be made private by screening. Otherwise, there will always be a feeling of discomfort.
There are three ways to lay paying – sand bed, dry sand-and-cement bed, or sand and cement mortar. Laying paving on a sand bed is the easiest and most commonly used method. To lay gravel paths or paving, start by removing the top 10 to 15 centimetres of soil, or more if the ground is soft. As the site for paving must not be soft, drainage might be necessary first.
Pack the remaining soil well. Lay 5 centimetres of hardcore for gravel; 5 centimetres of sand on top of 10 cm of hardcore for paving slabs. Gravel laid on hardcore lasts longer than if laid on soil as it tends to sink into the soil. Firm the foundation well.
It is essential to get an accurate level for paying slabs, especially for areas wider than a couple of metres. To achieve this, a ‘screed’ should be set up. First, drive in short pegs to set the level of the foundation.
Allowing for the thickness of the slab to come on top, use a long, straight piece of timber with a spirit level, to get the tops of the pegs to the correct height. A slight slope, to throw off water, should be built in at this stage – 1 centimetre in 1 metre is enough.
Lay two straight pieces of 5 x 5 cm timber beside the pegs and level with their tops. Fill in the sand accurately and firm it well, levelling all the time with a third ‘straight edge’ laid across the two pieces of timber.
When the sand is level and evenly firm, lay the slabs in position, leaving a very small gap to allow for manœuvre. Level and lay the slabs by degrees. Some cement – 1 part dry cement to 8 parts sand – can be used to give a firmer base. The cement sets in time.
If a kerb is to be used to retain the sides of paved or gravel areas, especially paths, it should be put in place before laying foundations. Stand the kerbing on a bed of sand and cement (3:1) and allow it to set. It must laid level, or evenly sloping. Rough kerbing can be put in place without fixing in concrete.
A useful kind of informal kerb is a mowing strip of bricks laid level with the soil of the lawn. It reduces the amount of lawn edge cutting and can be continued around the lawn edge – not just at pathways. The mowing strip need not be set in concrete.
Slabs can also be laid on a bed of wet sand and cement mortar (5:1) laid under each slab. The amount used should be enough to allow the slabs to be lightly tapped to their correct level. The level of the foundation needs to be accurately alid out with pegs beforehand and these pegs constantly checked off as slabs are laid. This is the best way to lay natural stone paving, which is often of varying thickness and very difficult to lay on a level sand bed.
Measure the area to be paved and work out how many slabs will be needed. One square metre will take 6.25 (40cm x 40cm) slabs, 4.2 (60cm x 40cm) slabs or 2.8 (60cm x 60cm) slabs. One tonne of sand covers about ten square metres to a depth of five centimetres. Measure the layout of slabs carefully to reduce the number of slabs that must be cut.