The advantage of double- or triple-board treads is that they drain water more quickly and they’re less likely to cup than single-board, full-depth treads. It’s standard practice to leave a ¼” gap between each board of a double or triple tread for drainage. If using risers, leave a gap of ¼” wherever the tread meets the riser, for ventilation and drainage.
Should you need to make any adjustments to account for variations on the ground, make up the difference on the bottom step. It’s OK if it’s slightly lower than the rest of the steps, provided the others are uniform in terms of rise. Be sure to leave a gap of at least 1/8″ between the ground and the bottom of the first riser.
Illustration of properly proportioned porch steps.
Planning a stoop
A cutaway layout for a set of porch steps shows the location of treads, risers, and supporting stringers in relation to one another. Steps and risers are uniform. The bottom step and supporting stringer rest on a concrete pad; the top of the stringer engages the house beneath the landing.
nosing The projection of a tread beyond the riser, usually rounded.
pitch line An imaginary line that runs at an angle along the front of the nosings of the treads.
riser The vertical element of the step between treads.
run The total horizontal travel of a staircase or steps.
stringer Inclined side member that serves as both carriage and face, also called a horse. Open stringers are more common than routed, closed stringers for porch steps.
tread The horizontal top of a step.
unit rise The vertical distance between one tread and the next.
unit run Depth of a tread (distance of travel per step) excluding nosing. Cutting the Stringers
Once you have all the rise and run measurements, use them to mark out the first stringer. For open stringers: Choose a 2″ x 12″ piece of rot-resistant red cedar, pressure-treated pine, or redwood with as few knots as possible. The stringer should follow the desired pitch line of the stair, and the cuts will follow in zigzag fashion to follow the rise and depth of each step.
• Lay out the cuts by placing a framing square on the stringer board; mark and check the positions of all before making any cuts. Align the blade and tongue of the framing square so that the rise and run dimensions fall on the edges of the stock. Once you’ve marked the first planned cuts, slide the square along to lay out the next, taking care to mark each step accurately.
• Leave a foot or two of extra stock at both the top and bottom ends of the stringer. You won’t know exactly where and how the ends will be cut until you determine where the stringer will land. The top anchor may require another 18″ of stringer, for example, if it continues under the porch. If the foot lands on a finished surface such as a poured concrete pad, the bottom riser will have to be “dropped” by the thickness of a tread to keep the stairs consistent.
• Use the first stringer to mark cuts for the second outside stringer and any additional stringers to support the stair carriage. As a rule of thumb, use one stringer for every 2′ of span. Before laying the treads, use a level and check in several places to make sure the base for your new stoop is square and level.
Concrete steps work well for stoops, especially in forgiving climates like southern California. Poured correctly, leveled, and back-filled with stone, gravel, or concrete block—not soil—they’ll last for decades.
Rails & Posts
New stoops that rise 30″ or more off the ground must comply with building codes regarding rail height, typically about 34″ to 36″ from the front of the tread. If any parts of a stoop that is original to the house are still present, by all means use them as a template for rebuilding, especially with architecturally important components such as top rails, spindles, and post caps.
You’re in luck if there’s an existing concrete platform underneath what will be the bottom of the stair run. If it’s in good condition, use it as a support for the bottom posts. Anchor the posts to the concrete with concrete screws. If the slab is missing or in poor condition, remove it and pour a new slab. It’s important that the post at the bottom of the stoop not directly touch the ground. If there isn’t a concrete pad, pour concrete piers to support the stoop posts. (A Sonotube collar works well for this.) Place a 4″ x ½” bolt in the middle while the concrete is still wet. After the concrete has cured for a day or two, slip a galvanized post base over the bolt and fasten with a washer and nut. Slide on the new post, making sure that it rests at least 1″ above ground level.
A simple two-step granite stoop at a Georgian entry is beautifully proportioned.
Anchoring and Skirting
To anchor a stoop with multiple steps to the house, fasten a 2″ x 8″ board to the faceplate below the door with large galvanized deck screws. Reinforce the bottom of the steps with a 2″ x 8″ board that runs between the exterior stringers. Butt any interior stringers into this support. To conceal open areas underneath the stoop but allow for ventilation, add skirting. A skirting apron is typically composed of latticed panels that are hung or hinged to the framing. Lay a bed of crushed stone underneath to keep wood from touching the ground.
The Pro Tip Looking for clues to what the steps originally looked like? If there’s no evidence at your house, look around the neighborhood for homes with original steps still in place. Take into consideration the type of construction (wood or brick, for instance) and whether one material—concrete, wood, brick—dominates.
The finished cap is made from cedar that’s been allowed to air dry for several months. Trim mouldings are cut from PVC composite and back-caulked to give them greater longevity.
When Chicago-area carpenter Bill Cigliano rebuilt the porch and stoop on his 1907 home, he milled new rails and balusters to match the originals from Red Grandis, a sustainable, tropical wood similar to mahogany. While new posts can be milled from a single piece of lumber, it’s difficult to get quality stock that will hold up to exposure from wind, snow, and rain. “Most of the
newel posts I repair rot from the inside out,” Cigliano says.
Bill Cigliano’s post caps are always beveled to direct water away from the wood. He draws newel post details to scale before constructing them, often giving owners two or three different profiles to choose from.
That’s one reason he builds his posts as 4″ x 4″ boxes of pressure-treated pine mitered and glued together at the corners, then slips them over a galvanized post base. He finds that treated pine is harder than cedar and less prone to cracking. All wood is back-painted (primed with oil-based paint on all sides) to protect it against moisture. He also staples ¼” PVC shims to the bottom of each post to prevent any wood from wicking up moisture from the ground.
Cigliano air dries clear, knot-free cedar stock for post caps in his workshop before milling them into shape. For shaped mouldings, he uses a PVC that won’t shrink or swell, such as AZEK, then caulks behind them to ensure low maintenance and longevity.