Decking has found favour in the garden in recent years. It is an excellent alternative to paving as it is durable, light and gives the garden a modern, contemporary feel. It can be built in almost any shape, colour and size, designed to suit personal tastes and budgets. It also enables a level seating area to be constructed in a sloping garden. Although it is possible to construct simple decks in your garden, seeking professional advice is recommended when constructing complicated designs or high, raised structures.
Which type of wood to use
Decking can be made out of either softwood or hardwood. The most popular type of timber used in the UK is softwood that has been pressure treated with a suitable preservative. Pressure treating involves deeply penetrating the wood with preservative by an industrial process that provides long-term protection against rotting and should last about 25 years. Standard components and decking boards are readily available in DIY stores, timber merchants and garden centres. Ready prepared decking kits are also available. Hardwood decking boards do not require pressure treatment.
Softwood suitable for decking
When using softwood, check that it has been pressure treated to avoid rotting. North American western red cedar: straight grained, few knots but a tendency to split and dent.
British spruce/European white wood: straight grained and few knots. Use for out of ground components only.
British pine/European redwood: clearly visible grain. Lower grades can have lots of knots.
British/North American Douglas fir: a prominent, wavy grain, the heartwood is naturally durable.
British/European larch: a prominent grain, sometimes knotty.
Southern pine: visible grain with few knots.
Hardwood suitable for decking
Hardwoods are generally more expensive, have a tighter grain and will not require pressure treatment with preservative because they have natural durability sufficient for decking applications. They can be more colourful than the beige colours of the pressuretreated softwood, although colour will fade when exposed to sunlight.
Teak: very durable with high strength, mid-brown.
Iroko: coarse grain, but not very visible, durable, brownish beige.
European oak: broad, straight to wavy grains, durable, pale beige.
Opepe: an insignificant grain but the wood can have an irregular coarse texture, very durable.
Jarrah: straight grain but not strongly marked dark brown.
Karri: stripped grain and very durable.
Balau: fine even texture, very durable and strong, beige.
Decking boards are usually available in sizes from 75mm wide to 150mm wide. Laying the wider boards is usually quicker because they cover a greater area. Each board, whether it is plain or grooved, should also have the edges rounded off to help any water to run off easily.
Site preparation
After working out the size and orientation of the deck, clear and prepare the site. Failure to do this properly will result in weeds growing up through the cracks between the boards and will look unsightly. Start by clearing the area of all vegetation and turf. Compact and level the ground leaving a gentle slope towards the outer edge of the deck to allow for drainage. Then lay a weed-suppressing membrane over the surface and cover with gravel. Now you are ready to begin.
