With my deck all done and every man and his dog coming over to have a look, it has become apparent that even a deck as low as mine still needs a step.
There are many ways to build a set of steps. If my deck was a little higher I could use a pair of stringers 50mm thick and 200mm deep and check the treads into those. The stringer method is more appropriate if your deck is up a level. For wider steps, a stringer running under the steps from the deck and fixed to the ground using a Bowmac bracket set in concrete is the way to go. Triangular blocks are nailed to each stringer to form a flat surface to attach the treads to.
But for what is essentially one step, neither of these methods is worth doing. I'm going to build a closed-in step - which is more or less a small deck.
For low steps or relatively small sets of cascading steps like a wedding cake, with the smallest one at the top and the largest at the bottom steps, this is my preferred method.
Importantly, the steps still need to be anchored to the ground and because I'm covering the outside of the step with decking timber I use posts on the inside of the framing, set in concrete.
Step height is a matter of choice but I recommend steps with no more than 150mm faces or drops. This seems to be the most comfortable height for most steps; any deeper and it can become a chore to get up and down them and any shallower they start to become a tripping hazard.
Measure the depth of the step from the top to the bottom, then divide that measurement by 150. That will give you the number of steps you need. If you are building steps between two fixed surfaces, like a deck and a driveway, you can either adjust the height of all the steps to fit or you can make the height correction on the bottom one only. I recommend the second option as it will be a lot less fiddling around. In my situation the step will be a little short but I'm able to bring the path up to the required height.
Set up a profile for the step using my string method of a couple of weeks ago.
Dig a 500mm hole for the post in each corner. The posts should be no more than a metre apart. If you need to put a set of posts in the middle of your staircase I would consider using the stringer method.
Build a frame for the bottom step out of 150 x 50mm h3 tanalised timber. Position joists to attach the decking at no more than 450mm apart, plus a joist running length ways to support the step above if required.
Position a post under each corner using galvanised straps. Then use sturdy pegs to set the entire step in place. Do a final check to make sure that it is level and at the correct height, then concrete the posts into place. Make sure that the concrete completely encases the post; self-reinforcing concrete is perfect for this.
Once the concrete is dry, mitre the face or riser of the steps first then attach the treads so they overlap the riser.
Using a sanding block, rub off any rough corners, then stain or finish to match the deck.