ADA ramp

Where a circulation path connects the room to a performance area, the accessible design standards require an accessible route to it. In practice that means a ramp, and the dimensions are not negotiable in the way stage sizes are.

The running slope may be no steeper than one in twelve. That single figure is what surprises people: a stage twenty-four inches high needs twenty-four feet of ramp run, and a thirty-two-inch stage needs thirty-two. The clear width is at least thirty-six inches, the cross slope almost flat, and a landing at least sixty inches long is required at the top and the bottom — so the real floor area consumed is the run plus ten feet, and more again where the ramp turns.

The rule that catches designers is the limit on rise. A single ramp run may rise no more than thirty inches. A stage higher than that cannot be served by one straight ramp at all: it needs an intermediate landing and a second run, which usually means a switchback, or a platform lift instead.

Handrails are required once a run rises more than six inches, at a height between thirty-four and thirty-eight inches, with edge protection along the sides.

None of this is a reason to lower a stage. It is a reason the ramp is drawn on the floor plan at the same time as the seating, because twenty-four feet of ramp is a row of tables.

Staging and rigging — owned inventory, our own crew, and a site survey before anything is specified.

• Stage stairs The steps up to a stage — where the trap is that a convenient riser height is also an illegal one.
• Stage deck The modular platform a stage is built from — four feet by eight in most of the country, with the height set by the legs rather than by the deck.
• Guardrail The barrier along an open edge — required by code above thirty inches, built at forty-two inches high, and carrying an exception for performance areas that is routinely misread as a blanket one.