
Lida Lewis
PASSIONATE DESIGNER
STORYTELLER
BUSINESS DEVELOPMENT PARTNER
WORKPLACE + HUMAN EXPERIENCE STRATEGIST
WELLBEING DESIGN ADVOCATE
CoStar Headquarters

What does it feel like to walk into a building that houses more than one company, and know within seconds whose door you've found?
That question sat at the center of my work on CoStar's headquarters relocation to Rosslyn — an independent design collaboration completed alongside 23/Consulting (principal Diana Horvat) as part of a multi-firm competition for the project. Our team was named a strong finalist, though the commission ultimately went elsewhere.
Before I opened a single drawing, I went to the building itself — multiple times. I walked the site during the day to read the pedestrian and vehicle patterns feeding into the lobby, then went back after dark to see how the tower read against its surroundings at night (and, frankly, how much it disappeared into them). I also drove a wider loop around the block, looking specifically for the longer sightlines that would matter most for any exterior lighting or signage intervention.
That site work led to the concept I brought to the team: separating the lobby experience and traffic flow for CoStar from the building's other tenants. CoStar would get its own arrival sequence — its own desk, its own identity — instead of sharing a generic multi-tenant lobby. From there, the design extended up through the occupied floors, organizing each one around a clear balance of collaborative gathering space (pantries, informal meeting areas) against quieter, focus-oriented zones, with stair and elevator lobbies treated as connective moments rather than afterthoughts.
The final presentation package included:
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Before photographs of the existing building and site
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Massing-model graphics illustrating traffic flow and the building's relationship to its contex
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Floor plans with programmatic zoning, showing where collaborative versus focus-oriented spaces land on each level
- Final renderings of the CoStar and shared building lobbies
It was a compressed, collaborative sprint — plans, renderings, and diagrams changing hands daily between the team — but the lobby-separation concept held from that first site visit through to the final boards.






































