I ve done alternating tread stairs before also called ship ladders.
Alternating tread ladder plans.
Designed to be used as a stair with users facing the direction of travel when climbing up and down.
The unused half tread is removed to provide more tread depth for improved safety and comfort.
This is a great option for people who dont have too much space in their offices or house for a regular long stair.
Alternating tread stair plans stairs may not seen many alternating tread staircases made to measure.
Is on the code makes no mention of alternating tread depths riser heights width overhead.
The idea behind them is your foot only uses half of the stair so you can cut the other half out to allow more step up room between treads that would otherwise overlap the space savings of a ladder but will full treads and a reasonable rise.
Industrial stairway with platform footprint.
But with an alternating tread stair the difference in height between the right and left treads is the unit rise using the guidelines of commercially built alternating tread stairs i try to get the unit rise between 6 1 2 in.
The steeper the angle the larger the rise.
As i can provide slipresistant stair inc bim content alternating tread each of your spiral and can have standard rise and.
Stair slope of either 56 or 68 degrees requires a smaller overall footprint than a standard stair.
You can save at least the half of the space without the problems of having smaller steps.