Mimicking the pipe-wrench-jaw-like multistory balcony near the top of BG Group Place (seen in blocky form at right in the rendering above), there’ll a tree-toothed notch carved into the eastern edge of the top floors of the just-unveiled design for 6 Houston Center. But this new $250 million spec office tower won’t just be a little more roughly cut than its neighbor — it’ll be a bit shorter, too. The 30-story structure is planned for the block surrounded by Rusk, Walker, Caroline, and San Jacinto streets, directly north of the LyondellBasell Tower at 1 Houston Center, on what’s currently a surface parking lot.

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A 9-level parking garage with a single underground floor will sit at the south end of the block and link to the taller 1 Houston Center (at left in the above rendering) with a 15-ft.-tall glass skybridge. A rooftop garden is planned for the garage top, which will connect to a “concierge floor” with a fitness center and conference rooms in the main building. There will be a coffee bar and a place to store bikes somewhere in the building, according to its developer, Crescent Real Estate Holdings.

The building’s 35-ft.-tall lobby (above) will face north onto Rusk St. and the eastbound trains of the new East End and Southeast rail lines (below). The design from HKS Architects includes 10-ft.-tall office floors (mirroring a daylight-boosting move by BG Group Place) and 12-ft. ceilings on the top floors.

Crescent’s CEO tells the Chronicle ‘s Nancy Sarnoff the company plans to begin construction this summer — whether or not it finds any tenants for the 300,000 sq. ft. of office space inside. Back in 2008, the company bagged out of plans for a different tower design on the same site, which it’s now owned for a decade.

Renderings: HKS Architects

Tree-Lined Sky Views