Los Angeles, CA

The Forum


The Forum, which opened in 1967, was designed by Charles Luckman Associates.  The circular building features an exterior arcade of white columns that rise up to support a reinforced concrete compression ring.  The roof, approximately 407 ft in diameter, is suspended from the compression ring, allowing for an open space free of interior supports.  The building was used sparingly from 1999, when the Los Angeles Lakers and Kings began playing at the Staples Center, until 2012 when The Madison Square Garden Company acquired the venue.  As part of a comprehensive rehabilitation and renovation project, SGH designed a replacement roofing system for this significant structure.

SGH was the engineer of record for the roofing design.  We investigated the existing roofing and determined the built-up roofing assembly on the main roof had exceeded its useful life.  We designed a replacement roofing system and highlights of our work include the following:

  • Selected a single-ply PVC roof membrane system for the main roof to limit the weight of the roof assembly on the structure and as a suitable solution for potential standing water
  • Designed a roof assembly for the anticipated wind uplift and obtained approval from FM Global to reuse the existing gypsum deck
  • Designed a tapered insulation layout based on anticipated deflection of the roof under suspended loads, including those during large events
  • Specified a fall arrest system for the perimeter of the roof to allow safe access for maintenance of the drains and scuppers
  • Developed details to reverse alterations, such as a metal screen wall added in 1989

With a successful rehabilitation and renovation, The Forum has been reinvented as a premiere entertainment venue once again.  The new roofing system will extend the useful life of the iconic structure, which celebrated its reopening with an enormous record spinning on the roof.

Project Summary



Completion Date


Construction Value


Repair & Rehabilitation | Preservation
Building Enclosures
Culture & Entertainment
The Madison Square Garden Company
Specialized Capabilities
Preservation | Roofing & Waterproofing

Key team members

Amy Hackney
Amy Hackney
Building Technology Region Head, West