Materials you'll need:

• Ready-mixed concrete (or sand, gravel and cement)
• Coloring pigment it required
• Bucket or platform for mixing
• Builders sand or aggregate
• Boards for edging
• Timber stakes
• Bituminous felt
• Screeding board
• Aggregate chips if required
• Polythene sheeting or sacking

Tools you'll need:

• Spade
• Hose
• Wooden float
• Stiff bristled brush

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A concrete patio creates an ideal area for outdoor entertaining, yet it needs very little upkeep, once it is properly poured. With care, it is well within the scope of the homemaker.

Tackle the job on a dry day and do not use too much water when mixing the concrete as this weakens it and leads to surface cracking. Too little water results in air holes giving the surface a honeycomb effect, so the consistency of the concrete is very important.

A mixture of one bucket of cement to 2 buckets of sand and 3 of gravel is a good balance Mix these thoroughly together then add about 1 bucket of water and mix to an even consistency.

Small jobs may only require a few bags of ready-mixed cement to which you add water and gravel. For very large jobs it may be worthwhile having ready-mixed concrete delivered to your property by truck, ready to pour.

1. Decide on the size and shape you want your patio to be. Make sure it will accommodate your outdoor furniture and a large party of guests.
2. If the patio is to be level with the ground, excavate the shape to about 75mrn deep plus an allowance for the layer of sand, which forms the bed. In poorly drained soil, use coarse aggregate as the base. For drainage, the patio should slope away from the house at the rate of about 6mm per 30cm.
3.Use clean builders sand (not beach sand). Builders sand is a coarse mix of different sized sand grains. Smooth out and tamp down the sand until it is well compacted. Damp the sand with your garden hose on mist setting and tamp down again.
4.Next make a formwork (edging boards which keep the concrete in shape until it dries) usually removed after the concrete is set so they can be of any handy timber such as 50mm x 10Omm­. Brace the outside forms with pegs of timber driven into the soil every meter or so.

The inside of formwork should be coated with diesel distillate to stop the concrete sticking to it. In a large area reinforcing mesh should be used. It usually comes in sheets of varying sizes set out in 10cm to 15cm squares. Cut so that it fits just inside the edges of the form­ work. Suspend it by tying pieces of wire at 45cm to 60cm intervals and attaching to strong pieces of timber that span across the area to be concreted, and sit on the formwork. This will ensure that the mesh is positioned in the middle of concrete for maximum strength. You are now ready to pour the concrete.

Note - Patios laid alongside the house should have an expansion joint (a strip of bituminous felt) laid between patio and adjoining building to allow for heat expansion and prevent the concrete cracking. Pour the concrete and spread it out evenly with a shovel, working it well into the corners and edges.
Now you can cut wire-holding mesh in position and remove timber. Use a length of straight board (called a screeding board) to even out the surface level with the top of the formwork.

When the water on the surface of the concrete begins to disappear, finish the surface by smoothing over lightly with a wooden float. To make the surface non-skid you can brush the concrete with a stiff bristled broom.

Exposed aggregate. The pebbly surface known as exposed aggregate can be created in 2 ways:

1. By letting the surface start to firm then gently hosing and brushing away the top layer of concrete to leave the aggregate in view.
2. By finishing the concrete as described then scattering handfuls of aggregate pebbles or marble chips over the surface and patting down to embed them. When the surface starts to fix, gently brush the cement off the top of the aggregate, spraying with a fine jet of water from the hose.

To cure the concrete. Allow to set until a finger pressed lightly on the surface leaves no mark then sprinkle with water and cover with polythene sheeting or sacking and keep damp to cure. You may need to hose down each day for about a week. Concrete can be walked on after 24 hours but ideally requires up to 6 days to fully cure, before wheeled traffic should be allowed on it.

Colored concrete. If you are unhappy with a plain grey surface, and don't want an exposed aggregate finish, special coloring pigments can be added to the cement before it is poured.

Note the concrete technique described here is mainly intended for patio surfaces which are only going to be walked over. For a driveway or other heavy-use surface, consult your concrete supplier about necessary reinforcing and suitable concrete mix.