Wooden Decking in Scottish Borders

1. Calculate the surface area for your decking Multiply the length (L) of your decking area by the width (W): L x W = Decking Surface Area (DSA) in m² 10 x 6 = 60m²
2. Work out the coverage of your deck boards Add your deck board width (DBW) to the expansion gap length (EGL), then add the deck board length (DBL) to the expansion gap width (EGW). Then multiply these numbers. (DBW + EGL) x (DBL + EGW) = Single Board Coverage (SBC) 0.144m + 0.005m = 0.149m 2.4m + 0.003m = 2.403m 0.149 x 2.403 = 0.358m²
3. Calculate the number of deck boards you need Multiply the SBC by 1.1 to allow for 10% wastage. Then, divide the DSA by the SBC. DSA / SCB x 1.1 = Total number of boards required 60m² / 0.358m² x 1.1 = 184.36 boards – so round up to 185 so you’re not left short.

• Have a step tread width of 900mm – if you don’t want them that wide, they should be no less than 760mm
• Add a central step riser to stairs wider than 900mm to prevent them buckling
• Add a step depth (the vertical distance between each step) of between 150 and 180mm if building your own riser, so the steps are at a comfortable depth

• Step treads (the actual step themselves)
• Step risers
• Coach screws
• Deck screws
• Saw
• Drill

1. Make sure the ground where you want to put your steps is level and firm. If it’s not, consider laying concrete or paving slabs to provide a secure surface for your steps to sit so they don’t sink.
2. Grab some joist off-cuts and cut them to the same width as your step treads. Attach them to the step risers at the top and bottom using countersunk coach screws.
3. Place the steps against the sub-frame of the deck; if you’ve put slabs down for support, make sure the steps sit in the middle of them. The longest edge of the stair riser should be on the slabs, and the short edge against the deck. Drill pilot holes through the step and sub-frame joist, then screw the step to the sub-frame with more coach screws.
4. After drilling pilot holes, screw the treads into the risers at each end with deck screws.
5. If you don’t want gaps between each stair, you can add joist off-cuts or deck boards. Measure the height and depth of the gap, then screw the off-cut or board into the step riser with two screws at each end.

• Paving slabs – old or cheap ones are fine
• Timber for the frame and legs
• Type 1 MOT hardcore

1. Mark out the area as we explain in ‘How to lay decking’. Then, dig to 200mm below where you want to surface of the decking to be.
2. Add a 50mm layer of hardcore and make sure it’s compact.
3. Build the decking sub-frame as we describe in ‘How to build a deck frame’.
4. Lay out paving slabs along the edges and in the centre of the area. This will help to spread the weight of the decking.
5. Set the decking frame on the slabs, checking for high or low points and adding off-cuts of timber where needed. Don’t forget to sand and seal these off-cuts with decking preservative.
6. Add your joists and then the deck boards, leaving the recommended gaps of expansion of between 5-8mm.

Usually, slipperiness is caused by algae or dirt on top of the deck or terrace. A full cleaning treatment should restore the natural grip of the wood or stone. If slipperiness is a persistent problem, consider installing grip mats in high traffic areas of the deck.