The Space Below: Connecting Transit, People & Tall Buildings

This fourth technical guide of the CTBUH “Space” series focuses on how tall buildings connect to the surrounding public realm, connect to other tall buildings and to major transit interchanges, particularly through grade-separated, conditioned pedestrian walkway systems. 

The CTBUH Urban Design Assembly concentrates on several issues affecting the urban habitat of tall buildings, including: What are the essential ingredients needed to improve the quality of life for those who visit, live and work in tall buildings within urban areas? What are the social and economic factors that affect these ingredients? What is the role of the tall building as a place-maker? How should tall buildings meet the street, how are they connected and how do they contribute to the public realm?  

One of the most important ways in which tall buildings contribute to the public realm is through their connections to the surrounding streetscapes and pedestrian networks. Often, these networks exist in climate-controlled environments, creating a network of connected tall buildings and interior open spaces. In cold- and hot-weather climates, these interior spaces can augment exterior gathering spaces as places for social interaction. That topic is the focus of this technical guide. Through 11 case studies, an under-sung but important layer of the city—the wide array of tunnels and bridges, populated with all kinds of commercial and social life—is revealed.

Principal Authors: James Parakh & Daniel Safarik
Coordinating Editor: Daniel Safarik
Layout/Production Editor: Tansri Muliani Wood
Additional Research: Isaac Work and Roberta dal Molin
Publisher: Council on Tall Buildings and Urban Habitat, Chicago, 2025
ISBN: 978-0-939493-92-0
Soft cover, 152 pages, 8.5"W x 11"H