New rebar coupler system allows interior buildouts to start sooner

By: Lewis Team

At Trammell Crow Company’s 1916 Boren, we’re using a new rebar coupler system to eliminate leave-out strips, allowing us to start interior buildouts more quickly. This marks the first time the system has been used in Washington state.

With typical concrete pours, large slabs are separated by unfilled strips—called pour strips—to accommodate concrete shrinkage during curing. The strips are filled in later, requiring significant reshoring and for formwork to remain in place on the floor below, which can impede progress on a buildout.

The new rebar coupler system at 1916 Boren—a life Science building in Seattle’s Denny Triangle neighborhood—allows crews to pour two adjoining slabs without leaving a pour strip between them. Instead, the concrete’s movement during curing creates a thin joint that can be grouted. The tubes inside the couplers are also grouted, locking the rebar into place.

This means formwork under each floor can be disassembled in one sequence, clearing the way for interior buildouts as the project progresses and allowing tenants to move in sooner.