Guide to Scaffold Stair Towers for Upper Level Access

Guide to Scaffold Stair Towers for Upper Level Access

Most crews access a scaffold the way they always have, which means climbing the frames or leaning a ladder against the outside. That works for a one-lift job and it stops working the moment the scaffold gets tall, the crew gets large, or anyone has to carry something up. A stair tower is the piece of the system that decides how a job actually flows, and it is usually an afterthought in the quote.

What a Stair Tower Is

A stair tower is a scaffold bay built with internal stair units so crews walk up instead of climbing. It uses the same frame components as the rest of the scaffold with stair flights and landing platforms threaded through the bays, so it is not a separate structure - it is the access bay of the run you were already building.

Because it is a walkway rather than a climb, it stays usable in wet and muddy conditions, it lets a worker carry tools and material with both hands, and it gives a safe route down for anyone who gets hurt up top. That last point is the one that general contractors on commercial sites ask about first.

Stair Tower vs Ladder and Frame Climbing

Climbing frames is legal, common and the fastest thing to build. It is also the access method that produces the most fatigue and the most near misses on a tall job, and it puts a worker's hands on the structure he is working from. Anyone who has climbed ten feet of frame with a bag of tools knows it is a task in itself.

Ladders leaned outside the scaffold solve the carrying problem and add a different one - the ladder has to be secured and the crew still has to step around the guard rail at the top. A stair tower removes both problems at once by making access part of the structure.

Erection and Tying In

Stair towers are heavier than a plain bay because the stair flights carry their own load, so the base has to be planned for it from the start. Footings, sills and plates matter more here, not less, and the bay that carries the stairs should be on the most solid ground in the footprint.

Tie-in requirements apply to the whole scaffold including the tower. A tower is often built on the outside face for convenience, which is fine, but it still needs the ties and the bracing the rest of the run needs - and the guard rails at each landing need to be complete before the flight above it is used.

When It Pays Off

The rule crews use is that a stair tower earns its cost somewhere around two lifts, or whenever the crew is large enough that people are queuing to climb. Add material that has to reach the platform by hand and the break-even gets lower.

On long commercial jobs it also shows up in the schedule. A crew that walks up arrives at the work with energy left, and the day's output reflects it.

Plan Access With the Scaffold

Access is not a detail to sort out on the second day. Deciding on a stair tower at quoting time is what stops a crew improvising one on site.

We stock scaffold frames and towers in Rowlett and can price an access bay alongside the rest of your run.

Everything ships from 5030 Dexham Rd. Ste. 103 in Rowlett, TX, and local crews can pick up the same day. Call 972-331-1090 and we will tell you what is on the floor right now.