Mark Top and Bottom Stringer Cuts

What happens in this clip

To complete the top of the stringer, turn the framing square 90 degrees and align the blade with the last marked tread line. Make sure it's perfectly lined up, then draw a horizontal line to finish off the top of the stringer. For the bottom of the stringer, line up the tongue of the framing square with the bottom marked tread, ensuring perfect alignment with the pencil mark and in the corner. Then measure and mark out the riser distance (7 and 5/16 inches in this case). This adjustment needs to be applied if your stringer is going to be attached to a subfloor first, and then finished flooring will be added on top. You need to drop the stringer by the thickness of the tread minus the thickness of the finished floor. For example, if your tread thickness is 1.5 inches, you need to remove that amount from the bottom of the stringer so that once the finished tread is added, your rise remains consistent.

Goal: Finalize the top and bottom cut lines of the stringer

What's used

Tools

• Framing Square
• Pencil
• Tape Measure

About the full video

This project provides a detailed guide on how to figure out the dimensions, lay out, and cut stair stringers for a basic set of stairs. It covers essential terminology, mathematical calculations for total rise, total run, unit rise, and unit run, as well as considerations for attachment methods and tread thickness. The instructions culminate in the marking and cutting of a wooden stringer using a framing square, circular saw, and hand saw.

Step 6 of 6: Trim the Bottom of the Stringers

The bottom of each stringer often has a triangular waste piece. You need to trim this off to create a flat surface. The amount to trim depends on your specific layout, but it's typically a straight cut across the bottom edge of the stringer where the lowest tread will sit. This ensures the stringer sits flush and supports the first tread properly. Measure and mark this trim cut accurately on all stringers.

Open this step in the guide

Every video in How to Lay Out and Cut Deck Stair Stringers

1. Step 1: Determine Stair Riser Height and Tread Depth

   • 0:06–1:32 Calculate Stair Dimensions
   • 0:19–0:57 Calculate Stair Dimensions and Stringer Type
   • 0:51–1:37 Calculate Individual Step Rise and Total Run

2. Step 2: Select Stringer Material

   • 0:00–0:03 Cut Stringers
   • 6:08–6:51 Stair Stringer Fabrication
   • 2:20–3:14 Mark and Cut Stringers

3. Step 3: Mark the First Stringer Layout

   • 3:10–3:59 Mark the Stringer Board
   • 6:59–9:34 Mark the Stair Stringer for Cutting
   • 6:12–7:01 Marking the Stringers

4. Step 4: Cut the First Stringer

   • 6:15–7:14 Cut Out the Stringer
   • 4:16–5:49 Cut Stringers
   • 15:12–19:27 Cutting the Stair Stringer

5. Step 5: Transfer Layout and Cut Additional Stringers

   • 8:43–8:58 Cutting Remaining Stringers using Template
   • 7:14–7:47 Replicate Stringers (Pattern Use)
   • 2:49–3:44 Layout and Cut Stringers

6. Step 6: Trim the Bottom of the Stringers

   • 7:25–10:59 Mark Top and Bottom Stringer Cuts
   • 7:30–8:22 Check and Adjust First Stringer
   • 8:10–9:35 Mark Top and Bottom Stringer Cuts (this video)