Steel Channel Stair Stringer Stairs in Advance Steel (Free Template)

The steel stair I build most often has two MC10x8.4 channel stringers, diamond plate steps and a channel-framed landing. It’s simple to fabricate, easy to handle and install, and it saves my clients money. I use it on jobs all over Chicago and the suburbs, and it has always passed inspection for me. Below is how I model it in Advance Steel, step by step, with a free template so you don’t have to set every parameter from scratch.

Download the template here

Code note: the riser and tread sizes below are from IBC 2021 Section 1011.5.2. Chicago, and many other cities, have their own code. Always check the code that applies to your job, and have the design checked by the engineer of record.

Can I watch it instead?

Why build stairs with channel stringers?

Standard shape. MC10x8.4 is a common channel, so it’s easy to get.
Simple cuts. The stringer ends are straight cuts, plus one notch on the upper flight.
Light. Easy to handle and install without big equipment.
Simple landing. The same channel frames the landing, with angle supports and a cover plate.

How do I set up the model?

Step 0: open the template

Unzip the download and open the file. Delete the stair and floors in it. You’ll make new ones.

Step 1: make reference floors

Go to Objects > Other Objects > Rectangular Slab.

For the start of the diagonal, type 0,0,0 and press Enter.
For the size, type 8′,12′ and press Enter.
In the dialog, change the size, position or thickness if you need to, then close it.

Draw a vertical line the height of floor to floor. Here it’s 10′-4″.
Select the slab, then Tool Palette > Modify > Copy. Copy it from the bottom of the line to the top.

Change the color of your helper lines so you can tell them apart from the model.

How many risers do I need?

Divide the floor-to-floor height by the maximum riser height and round up.

IBC 2021 Section 1011.5.2 allows risers from 4″ to 7″ and treads of at least 11″. (Inside R-3 dwellings and R-2 dwelling units it allows a 7¾” riser and a 10″ tread.)

10′-4″ = 124″. 124 ÷ 7 = 17.71, so 18 risers. Each riser is 124 ÷ 18 = 6.89″.
With a landing halfway, that’s 9 risers per flight.
Section 1011.5.4 allows only 3/8″ difference between the biggest and smallest riser or tread in a flight, so divide evenly. Don’t round each step.

In Advance Steel:

Type CAL to open the calculator and do the math.
Draw a line from halfway between the floors down to the lower floor.
Type DIV, press Enter, select the line, type 9 and press Enter.
Select the line and the division points, type G and press Enter to group them.

How long is the run?

A flight with 9 risers has 8 treads. 8 × 11″ = 88″.

From the edge of the lower slab, draw an 88″ horizontal line.
Draw a vertical line for the first riser.
Move the 9-riser line to the other end of the 88″ line.
Move all the lines 1½” toward the middle of the slab. That’s the flange width of the MC10x8.4 stringer.

How do I make the first flight?

Step 4: place the stair

Go to Home > Extended Modeling > Straight Stair.

Pick option 0 – Start and end points.
Click the top of the shorter line, then the top of the longer line.
Pick which side the stair goes on: 0 left, 1 middle or 2 right.

Step 5: load the template settings

Go to Properties > Library and pick 3-11 Wide Stair MC10x8.4.
Go to Landings > Top Landing Profile and clear Create front and rear.
Close the dialog.

The stair should look like this:

How do I frame the landing?

IBC 2021 Section 1011.6: the landing has to be at least as wide as the stair, and at least as deep (in the direction of travel) as the stair width or 48″, whichever is less.

Step 6: perimeter channels

Hide the top parts of the stair.
Draw a rectangle (REC) the size of the landing and move it to the top of the first flight.

Go to Home > Objects > Beam from Line, select the rectangle and press Enter.

Answer Y or N to delete the helper lines.
Pick MC10x8.4 in the dialog and close it.

Step 7: inner angle supports

Draw a line from the middle of one channel to the middle of the opposite one. Trim it with TR if you need to.
Copy it 24″ each side (or whatever spacing the job needs).
Beam from Line again, select the lines, and pick L4x4x1/4.
Adjust the offset and rotation so the angles sit right, then close the dialog.

Step 8: miter the corners

Tool Palette > Features > Miter. Select two perimeter channels and press Enter. Do every corner.

Step 9: cope the angles

Tool Palette > Features > Cope, Parametric. Select the channel, press Enter, select the angle, press Enter. Do both ends of every angle. More on this in copes in Advance Steel.

Step 10: cover plate

Move the UCS to the top corner of the landing (Tool Palette > UCS > Move UCS).
Home > Objects > Rectangular Plate, 2 points. Click two opposite corners of the landing.

Set the thickness in the dialog and close it.

Step 11: drop the landing

Lower the landing and plate by the plate thickness (3/8″ here) with M (Move), so the top of the plate is at the landing level.

How do I finish the stringer ends?

Step 12: cut the top of the stringers

Move the UCS to the top corner of the landing, just under the plate, and rotate it so the XY plane is vertical.

Tool Palette > Features > Shorten at UCS. Select both channels and press Enter.

Rotate the UCS so the XY plane is horizontal and run Shorten at UCS on both channels again.

Step 13: top cap plates

Home > Objects > Rectangular Plate, 2 points. Click two opposite corners where the plate goes, and set thickness and position.
Weld it to the channel with Home > Objects > Weld Point (pick Continuous if you want).
Copy the plate to the other stringer and weld it.

Step 14: cut the bottom of the stringers

Put the UCS at the bottom of the stair with the XY plane horizontal.

Shorten at UCS on both channels.

Rotate the UCS so the XY plane is on the face of the stringer and run Shorten at UCS again.

Step 15: bottom plates

Rotate the UCS square to the face of the channel.
Add a Rectangular Plate, 2 points and set thickness and position.
Set the UCS back to World (Tool Palette > UCS) and copy the plate to the other stringer.

The first flight is done:

How is the second flight different?

Same steps, except the bottom of the stringers sits on the landing, so the stringers get a notch instead of sitting flat on the floor.

Put the UCS parallel to the stringer and 1½” from the first riser, with the XY plane vertical.
Run Shorten at UCS on both channels.
Rotate the XY plane so it’s vertical and parallel to the stringer.
Tool Palette > Features > Rectangular contour, 2 points. Select the first stringer and draw the rectangle to cut out.
Do the same on the other stringer.

What does the finished stair look like?

What mistakes should I watch for?

Rounding each riser. Divide the total height evenly. The code allows only 3/8″ variation within a flight.
Using residential sizes on a commercial job. The 7¾”/10″ exception is only for R-3 and inside R-2 dwelling units.
Open risers. IBC 1011.5.5.3 requires solid risers except in a few cases. Where open risers are allowed, a 4″ sphere must not pass through them (some exceptions).
Forgetting the rails. Handrails and guards are a separate step. See handrails in Advance Steel.
Skipping the engineer. The channel, angle and plate sizes in the template are the ones I use. Your stringer size depends on the span and load. Have it checked.

For every stair option in Advance Steel, read stairs in Advance Steel.

If you’re looking at hardware or software upgrades, my toolbox page lists the tools I use and any discounts I know of.