Greengates Builders Merchants

Building a Raised Deck Step-by-Step

Building a raised deck is a rewarding project. Once completed, your new deck will provide a versatile addition to your outdoor living space. In this edition of the Greengate's local builders merchant blog, we'll share a simple step-by-step guide to building a square raised deck.

All of the materials you'll need are available to purchase at the most competitive price from the Greengate's website.

  1. First you will need to prepare a level area for your deck and ensure it is completely free of any weeds. 
  2. Create a framework using timber cut to the required length. Join the pieces of timber together using quality screws. Measure from corner to corner to ensure the framework is perfectly square, adjusting if necessary.
  3. Next, cut four blocks of timber to the required height of your deck. Screw the blocks into each corner of your prepared frame, making sure that they are totally flush with the top. As the legs will be supporting the weight of the deck, you should use a minimum of three screws to attach each block.
  4. Most decks will be sitting on soil or grass and so will required slabs or blocks placed underneath, providing a stable base and spreading the weight load. Put the slabs or blocks into position and use a spirit level to check the frame is aligned correctly. 
  5. Three joists should be sufficient for small decks: one joist will be in the centre and the other two at the middle-point between the centre joist and the edges of the frame. Measure and mark where the joists will go.
  6. Measure across the interior of the frame at the marks before cutting lengths of timber to these measu­rements. Fix the joists in place using a hammer so that they are flush with the top. Screw into place from the outside of the frame. 
  7. Make and use additional legs to support the joists, spacing them at intervals of 1m. Repeat step 4 for these additional legs.
  8. Measure the frame's outer sides and cut decking boards accordingly. Use a square to mark the cutting lines for a straight edge. The facing should then be countersunk and screwed to the frame, making sure that the facing is flush with the top.
  9. Start laying the deck, measuring across the frame's top and cutting boards to the right length. The first board should be placed flush with the frame's outer edge and facing, at right angles to the joists. Mark each joist's location as you go. 
  10. Mark screw holes over each joist's centre. Use a sharp countersink to leave clean holes. It may be necessary to drill pilot holes. You should use a minimum of two screws per joist for each board. 
  11. Incorporate an expansion gap of around 5mm between each decking board to allow for natural thermal expansion of the timber. 
  12. Continue this process until the raised timber deck is complete.

Your new deck is now ready to enjoy! Check out the Greengate's website to find all of the materials you'll need.

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