Wooden exterior stairs often provide entry into a home from a patio or deck. Wooden steps are typically pressure treated lumber. While you can make your own risers, you can also purchase pre-made stringers that can save the time of cutting all of the angles. If you choose to make your own wood stringers, keep in mind that the average riser follows a 7:11 ratio. That means each step rises 7 inches and measures 11 inches across. Before building any wooden steps on the exterior of your home, make sure that you have all building permits in hand.
Prepare the ground under the new stairs. It needs to slope away from the house. Add fill dirt as necessary. Unless you plan to set the bottom of the stairs directly on the ground, position cement pavers or bricks at the bottom of the stairs for them to rest on.
Measure how many steps that you need to build. Measure from the bottom of the door's opening to the ground. Divide by 7 since that's the height of a typical step. Subtract one, because that's the bottom of the doorsill.
Measure the width of the steps. If your steps are wider than 36 inches, you need a stringer for every 16 inches of width in addition to the two outside stringers.
Cut the 2-by-4 inch anchor board the width of the opening minus 3 inches. Center it under the door opening. Attach it to the house. If the house has masonry siding, use appropriate anchor screws to secure the anchor board.
Hold one stringer level with one end of the anchor board. Attach it to outside end of the anchor board with corrosion resistant screws. Repeat the process on the other end of the anchor board. If you are putting additional support stringers in place, cut 1 1/2 inches off the top of them with a circular saw. Toenail them in position so that they are flush with the anchor board.
Cut a piece of 1-by-8 lumber to create the stringer face. Cut this vertical piece so that it's flush with the outside edges of the stringers. Screw it in position on both of the outside stringers and the support stringers.
Add 1 inch to each end of the bottom step. Center the step in place on the stringer. Attach it to the outside stringers as well as the support stringers.
Continue working your way up the wooden steps, alternating between the stringer face and the stair tread.
Some municipalities do not require the stringer faces to enclose the steps. If that's the case, you may omit them and leave the stringers open.
Always use personal protective equipment, such as goggles, when working with power tools.