Build box step stairs for a deck with these easy instructions. This DIY project shows how to assemble the risers and treads, make the stringers, attach them to the support posts and then nail or screw each side of the steps into place. The best way to build box step stairs for a deck is by using 2×6 or 2×8 treated lumber for the framing, and you can use pressure treated or kiln dried lumber for your steps and stringers.
A box step stair is made up of a ladder-type framework, called stringers. Stringers are the bed that holds the stair riser and tread board in position, as well as supports them both vertically and horizontally. They can be built out of many materials, but for our example we will build ours out of pressure treated lumber.v
Building box step stairs for a deck is a simple project that can be done over the course of several weekends. Box step stairs are generally used in lieu of a single wide stair at the entrance to a deck, and they also work well in situations where space on either side of the stairs would result in an area too small to use. The box steps don’t require special tools or skills other than basic framing knowledge, and they’re just as strong as any other type of stair.
Put together all of the parts for the rise and run of the stairs.
Calculate the rise and run for each step. The rise is the distance from the bottom of one step to the top of the next, while the run is the distance from front of one step to front of next. Make sure all your measurements are straight down or up don’t account for diagonal measurements because those will be built into your stair structure.
- Rise = 4 inches (10 cm)
- Run = 6 inches (15 cm)
Fasten the parts for each step together to form two boxes with a top rail. The top rails will serve as a handrail for the stairs.
The top rails will serve as a handrail for the stairs. Fasten the parts for each step together to form two boxes with a top rail. The top rails will serve as a handrail for the stairs.
Position the first box under one end of a straight 2×6 board and adjust the box until it is flush with the back edges of the deck frame.
Now that you have the first box in place, it’s time to glue and nail it into place.
Position the first box under one end of a straight 2×6 board and adjust the box until it is flush with the back edges of the deck frame. Then pull out your speed square (or checker) and draw a line along the bottom edge of this board all the way across both sides of this piece, as shown in Figure 3-8 below. This will act as your guide so that when you apply nails at even intervals, they will be placed consistently across every side of all four sides of this piece.
Now measure over 1″ (25mm) from each corner and make marks for two more nails one on each side at each mark location and drive these two nails into place where marked, as seen here:
Fasten a 2×6 cleat to each inside face of the box, flush with the bottom edge of each. Toenail or screw through each cleat into its respective side of the box.
Fasten a 2×6 cleat to each inside face of the box, flush with the bottom edge of each. Toenail or screw through each cleat into its respective side of the box. As you work, keep an eye on your measurements to make sure that all four sides are exactly equal in length.
To attach the top rail, first measure and cut three pieces at 3 inches longer than your desired height (including both steps). Then cut one piece at 16 inches long for a handrail (or more if you want more space between steps). Now measure and mark out where you want your treads to go on all four sides of the box—these should be around two inches from each edge so that when someone walks up or down there will be room for their foot without hitting anything sharp like nails sticking up from under their shoe. You may need to move some nails back toward their edges slightly if they’re too close but not quite touching them; this shouldn’t cause any problems later on when building stairs since we’ll be using pressure-treated lumber anyway.
Move the first box into position under one end of a straight 2×6 board and adjust it so that it is flush with the back edges of the deck frame.
The first box should be positioned under one end of a straight 2×6 board and adjusted so that it is flush with the back edges of the deck frame.
Fasten a 2×6 cleat to each inside face of the box, flush with its bottom edge; toenail or screw through each cleat into its respective side of the box.
Next, you’ll need to fasten a 2×6 cleat to each inside face of the box, flush with its bottom edge. Toenail or screw through each cleat into its respective side of the box.
For example, when you’re attaching your first cleat (the one shown in red) to the left side of your box frame, align it so that it’s flush with the bottom edge and then nail or screw through both pieces.
Step 6: Position and Attach Remaining Stairs
Position and Attach Remaining Stairs
- Align steps with back edges of deck frame. The steps you are building should be aligned with the back edges of the deck frame. You may want to use a carpenter’s square or other level tool to make sure your measurements are accurate, but as long as everything is straight, you won’t have any problems.
- Align top rail with back edges of deck frame. Positioning your top rails is just as important as positioning your step frames; if it is off by even an inch or two, it could lead to problems later on when you start putting boards across them for flooring or railing purposes! Once again, use whatever tools are necessary to ensure that this alignment matches up perfectly before proceeding any further with construction efforts
Fasten each succeeding stair in place against its preceding stair by aligning its back cleats with those above them.
To fasten each succeeding stair in place against its preceding stair, you’ll need to align the back cleats with those above them. This can be done by using a transit or level and marking the back of each new step at the same location as its predecessor. Next, use a tape measure to make sure that each succeeding step is identical in length to its predecessor and use plumb bobs hung from its front edge to check for squareness. If your cuts were accurate, this process should be quick and easy.
We hope these instructions for building box step stairs for a deck have helped you understand the process better, so that you can enjoy your time on the porch even more.