Before You Start

It is best to plan your deck on paper first. The joists and decking boards come in  2.4m, 3.6m and 4.8m lengths, so think about how you can best use these sizes without creating excessive waste or unsightly joints.

Make sure that your deck is not going to obscure access to drain/manhole covers. If your project requires you to concrete in support posts, you should check for underground pipes and cables. Very large decks and raised decks may require planning permission.

Safety First!

Take normal safety precautions when working with timber products. Wear gloves to avoid splinters and a mask when cutting to avoid the inhalation of dust. Wear goggles when using circular saws, drills or sanders and always use an RCD device when using any power tools outside.

Preparing The Area

Mark out the area you plan to deck using wooden pegs and a string line – this will also help you visualise the finished size of your deck. If you are covering a lawned area you should lift the turf first and then cover the bare earth with a landscaping membrane to retard the growth of weeds. Where possible uneven ground should be levelled out, however if this is not possible the higher end of the deck can be supported with timber posts.

Constructing Your Framework

The design of your framework will depend on which pattern you plan to use for your decking. There are three main decking patterns – chevron, diagonal and horizontal. Incredibly intricate designs can be created by breaking the deck into modules of these three basic styles.

Pressure treated 100mm x 47mm joists are ideal for building the frame for a deck measuring up to 3.6m wide or a deck that is sitting on a concrete pad. For larger or raised decks 150mm x 47mm joists are more suitable.

If your deck sits on soft ground you will need to support the frame to prevent it from sinking or going out of level. The easiest way to do this is to either put down a 25mm deep bed of gravel for the frame to sit on, or stand the frame on concrete pad stones bedded down at no more than 1.80m centres. If your deck is raised off the ground you will need to support it with 100mm square timber posts. These posts should be spaced at no more than 1.20m centres, bolted to the frame and concreted in to a depth of 600mm.

Construct the outside of your frame first and then fit in the intermediate joists at no more than 600mm centres. Each joint should be double fixed with 4 inch screws. As you build up the frame, check at regular intervals that it has remained level and square.

Fixing Down The Decking Boards

Loosely lay out the decking over your frame. This will enable you to correctly judge the spacing of your boards. Once you are happy with the spacings, the boards should be cut to length and secured to the frame using two 65mm deck screws at every joist. The screws should be located approx 15mm in from the edge of the decking board and inserted in a grove to help obscure them from view.

If you intend to add either a balustrade, deck panels or a pergola to your deck you should bolt the appropriate posts to your frame first and then cut your decking boards around them.

There will be a detailed guide covering various ways of decorating your deck in ‘Constructing A Garden Deck Part 2′ which is coming soon.

You can purchase everything you need to build your deck from our on-line store.

CLICK HERE TO GO TO THE DECKING CATEGORY