Decking can be built in almost any shape, colour or size, which means you can design it to suit your tastes and budget. It's possible to construct simple decks yourself, but professional advice is recommended when constructing complicated designs or high structures.



Choosing your materials

You can use softwood or hardwood for decking. The most popular choice in the UK is softwood that's been pressure treated with a preservative to prevent rotting.
Grooved decking boards

Standard components and decking boards are available from DIY stores and timber merchants, and should last about 25 years. Ready prepared decking kits are also available. Hardwood decking boards don't require pressure treatment.

Always ensure the wood has been obtained from a sustainable resource - look for the Forestry Stewardship Council (FSC) label. See http://www.fsc-uk.info for more details.

Decking boards are usually 75mm to 150mm wide. The wider boards are quicker to lay (because there are less of them), but narrower boards are often considered to look nicer.

Coloured deck

Grooved boards are available; these offer better grip particularly when it's wet. It's possible to choose coloured boards, too, although you can always paint the decking once it's built. Whichever type you choose, it should have rounded edges to protect feet and improve drainage.
Site preparation

After working out the size and orientation of the deck, clear and prepare the site.

Nothing spoils a new deck more than weeds growing through cracks in its boards, so before you start clear all vegetation and turf from the area. Compact and level the ground, leaving a gentle slope towards the outer edge of the deck to allow for drainage. Lay a weed-suppressing membrane over the surface and cover with gravel.
Tools required

* drill
* saw
* screwdriver
* set square
* spade
* spirit level
* tape measure

Materials required

* ballast
* cement
* blocks for the posts to rest on
* bolts to support the outer frame
* decking boards (100mm x 25mm/4in x 1in)
* joist hangers
* stainless steel screws, countersunk
* wooden joists (150mm x 50mm/6in x 2in)
* wooden posts (100mm x 100mm/4in x 4in)

Step by step
Finished decking

The basic principle of constructing a deck is to attach the decking boards to a timber frame that consists of horizontal joists attached to vertical posts. It's always advisable to consult a professional when undertaking a major building project. However, here's a guide for constructing a small decking area.

1 Measure out the area the deck will cover and work out where the posts will go. A deck should be supported by posts on all corners and every 1.5m (5ft) around the perimeter, although more posts are required if the deck will be supporting heavy loads.

2 Dig holes 300mm to 400mm (12in to 15in) deep and 300mm (12in) wide for the posts. Put a building block in the bottom of each hole and place the post on top of this. Use a spirit level to make sure the posts are upright, then fill the holes with concrete. You must wait for the concrete to harden before continuing with construction, which should take one to two days.

3 Using bolts, attach the joists to the outside of the posts at the desired height to form the outside edge of the frame. Leave the posts long, as you can attach rope later to form a banister.

4 Attach joists to the inside of the frame every 300mm to 450mm (12in to 15in), using either joist hangers or screws.

5 To improve the stability and prevent any sideways movement from the deck, add shorter lengths of wood (150mm x 50mm/6in x 2in) every one to two metres (4ft to 6ft), perpendicular to the inside of the joists.

6 Screw the decking boards to the joists, leaving a gap of 6mm to 10mm between each board. This will allow the boards room to expand during wet periods. It will also ensure sufficient drainage and ventilation. If using hardwood, drill the holes in advance. Decking boards are usually laid at 90 or 45 degrees to the joists. Always lay decking when the boards are dry.

7 Once the decking boards are attached, use string to form a straight line along the edges of the deck and saw them all off in one go. Allow the boards an overlap of about 5cm (2in) over the frame. Paint the cut ends with a sealant to prevent water penetrating the deck.

8 Paint the deck with a coloured deck stain if required and coat with a clear water repellent.
Care and maintenance

* Furniture should be placed on rubber feet or mats to minimise damage.
* Put pots on bricks to allow the air to circulate and to prevent a build up of mould.
* Check bolts and screws regularly and tighten if necessary.
* Regularly clean the deck with a brush to remove dirt. A stiff brush should also remove mildew and algae.
* Occasionally remove mildew, algae and dirt with a pressure hose or deck-cleaning liquid.
* Once a year, add a clear water repellent.
* Check for damaged boards and replace as necessary.