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How To Build L Shaped Stairs - Part 5

Free Downloadable Staircase Calculator (requires Excel) - works in conjunction with this information.

Letters in Orange signify that the formula is on the free automatic staircase calculator.

The previous page dealt with a landing that could be placed anywhere, no space or obstructions limiting its positioning.

In many cases building an L shaped staircase is a necessity due to obstructions, walls or space limitations.

In these cases the dimensions of the risers, treads are determined by the position of the landing rather than the other way around.

The landing should be no less than the width of the staircase in both directions plus one tread depth in the direction of staircase form the upper floor to the landing.

If the staircase is 36″ wide which becomes the minimum dimension of the stair landing. Having this information allows you to determine the total run of the upper staircase - the staircase running from the upper floor to the landing.

measuring the stairwell opening
Figure 1 - Stairwell Opening

Measure the opening of the stairwell as shown in Figure 1, in the example we are using 86″.

The total run of the upper staircase is:

K Stairwell Opening - Landing Width = Total Run of Upper Staircase

86″ - 36″ = 50″

If you are using a hanger board to mount the upper staircase, you must deduct the thickness of the hanger board from the total run.

The finished landing height is:

L Total Rise - (No. of Risers x Stair Rise) = Finished Landing Height

106 3/4″ - (6″ x 7 1/2″) = 61 3/4″

Upper section of <q>L</q> staircase attached to upper floor and landing
Figure 2 - Upper section of L staircase attached to upper floor and landing

The lower staircase, the staircase from the landing to the bottom floor would be calculated in the same manner as shown in Figure 3.

L staircase upper flight of stairs
Figure 3 - L shaped staircase upper flight of stairs

The staircase from the landing to the bottom floor is built and installed in the same manner as a straight staircase, as if the landing was the upper floor.

Continued...

Straight Staircase

Winder Staircase

Staircase Terminology

Repairing Stairs

Stair Tread Repair Or Replacement