Unipec

Unipec: Interconnecting Feature Stair

Project Overview

For Unipec’s Houston office, Contract Fabricating Services fabricated and installed the steel structure for a two-story interconnecting feature stair, the architectural centerpiece of the renovated space. The stair connects two floors of a high-rise office tower through a new opening in the existing floor slab, with views of downtown Houston and Buffalo Bayou on the way up.

Our Scope

Feature stair structure: A two-flight steel stair with plate steel stringers and pan treads, fabricated in our Houston shop and assembled on site.
Oversized lower landing: A broad steel landing platform at the base of the stair, designed to extend into a built-in seating area that doubles as a gathering space and informal amphitheater.
Upper flight to existing structure: The upper run rises to the floor above and ties into the edge of a new opening cut into the existing concrete slab.
Guardrails and handrails: Steel handrails and guardrail supports along both flights and around the slab opening.
Field installation: Our crews brought every piece into an occupied high-rise and fit, welded, and set the stair in place.

The Challenge

Adding a feature stair to an existing tower leaves no room for error. Every steel component had to be sized to travel up through the building, then fit around existing concrete beams and tie precisely into a slab opening cut into a structure built decades earlier. The stair also had to be built to finish-grade tolerances: wood cladding, glass guardrails, and integrated tread lighting were installed directly over our steel, so any deviation in the structure would have shown in the finished design.

The Result

A striking feature stair that turned a two-floor office into one connected workplace. The finished stair, with its sculpted wood cladding, glass guardrails, and built-in seating, became the signature space of Unipec’s new office, built on a precisely fabricated steel structure that disappears into the design.