Why HVAC Techs Hate Alternating Tread Stairs—And What Architects Should Use Instead

Alternating tread stairs—often called witch stairs—might seem like a clever solution on paper. They save space, they check some compliance boxes, and they’re marketed as efficient. But talk to the people actually climbing them—HVAC techs—and you’ll hear a different story.

They’re not practical, they’re not safe, and they make a tough job even tougher.

Here’s why HVAC pros hate them—and what should be used instead when designing for roof or platform access.

1. HVAC Techs Don’t Walk Blueprints—They Carry Gear

Alternating tread stairs require a specific stepping pattern. But HVAC techs aren’t climbing for fun—they’re carrying tool bags, gauges, refrigerant tanks, and filters. On steep, staggered treads, those loads shift dangerously.

There's no solid platform to stabilize, no margin for an off-balance step. Every movement becomes a calculated risk. And it doesn’t help that these stairs often land in cramped corners or behind bulky equipment.

2. They Fail in the Conditions That Matter

These stairs might pass code—but they don’t pass real-world use. HVAC work doesn’t happen in controlled environments. It happens on wet rooftops, in icy conditions, and under pressure to finish quickly.

Alternating tread stairs, with their steep angles and narrow steps, are one of the worst things to navigate in those conditions. The result? Slips, slowdowns, and increased risk every time someone climbs or descends.

3. They Get Installed—Then Avoided

Here’s the part that rarely shows up in design conversations: techs avoid these stairs whenever possible.

They’ll bring their own ladders. They’ll find alternate routes. In some cases, they’ll delay service or ask for additional safety measures before accessing equipment. That’s not efficiency—that’s a failed design.

If a staircase gets installed and no one wants to use it, it’s not a solution. It’s a liability.

A Safer, Simpler Alternative to Alternating Tread Stairs

Fixed ladders are already part of most commercial and industrial projects. They’re familiar, space-saving, and expected. The real issue is what happens at the top—where many injuries occur during dismount.

That’s where Ladderport’s LadderReceiver comes in. It provides a stable, OSHA-compliant entry and exit point at the top of a fixed ladder. It secures the ladder to the structure and gives techs the kind of support and confidence they need to safely transition to a roof or platform.

Design With HVAC Techs in Mind

It’s easy to default to whatever’s in the spec book. But if the result is something that slows down techs, frustrates crews, or increases fall risk, it’s time to rethink it.

Witch stairs might meet code—but they don’t meet the needs of the people who actually use them. LadderReceiver does.

Need a spec sheet or CAD file for LadderReceiver? Request a quote today.