Alternating Tread Stairs

The Lapeyre® Alternating Tread Stair features a unique tread design which provides greater tread depth than vertical ladders or ship's ladders.

The alternating tread stair:

  • Allows comfortable face forward descents at steep angles.
  • Includes close fitting handrails which provide support.
  • Has a cushioned central stringer which virtually eliminates the possibility of hitting the nosing of a tread.

Common applications include:mezzanine access, roof tops or roof hatches, equipment access, conveyors, catwalks, storage tanks, crossover systems, or just about anywhere you would use a fixed ladder or need steep stairs.


Stair Design Details

Table 1: Alternating Tread Stair Options
Stair Specs Steel Aluminum
Heights Custom height built
Standard Handrails:
 56° - 36" to 240"
 68° - 42" to 240"
Optional Handrails:
 48" to 240"
Flush Handrail:
 48" to 240"
Custom height built
Standard Handrails:
 24" to 216"
Optional Handrails:
 55" to 216" inches
Angles 56° AND 68° 68° ONLY
Material with Finishes -Carbon Steel in Safety Yellow Powder Coat
-Carbon Steel in Gray Primer Powder Coat
-Carbon Steel in Iron Gray Powder Coat
-Carbon Steel, choice of colors .
-Carbon Steel in Hot Dip Galvanized
-Stainless Steel with Natural
Natural Finish ONLY



How the Alternating Tread Stair Works

How ATS Works -Convential How Steep Stairs Work How Lapeyre Stairs Work
Conventional Stair Steep Stair Alternating Tread Stair
Imagine walking down (or up) a conventional stair. Each foot normally uses only about half of each tread, stepping out and over the unused section (shaded red). On a steeper stair or ladder, the unused half tread becomes an obstacle, significantly reducing the usable tread depth of the tread directly below. As the angle increases, the problem becomes worse. In contrast, the Lapeyre stair removes the unused half of each tread, allowing the foot to reach the next tread in a straight, direct line, providing more usable tread depth.