Federal Building

Los Angeles, CA

Stronghold Engineering, Inc. served as the prime contractor for this project that called for comprehensive seismic and life safety renovations of over 300,000 square feet in the basement of the Federal Building in downtown Los Angeles, Calif. The contract included complete abatement of all hazardous materials, seismic strengthening and modernization with major structural steel components, all new HVAC ductwork, fire sprinklers, new lighting and fire alarm upgrades. This public building remained occupied and operational during the entire construction period. Stronghold coordinated work with the owner to ensure the safety of construction personnel, users and the public.

Stronghold self-performed approximately 35% of the work for this project, including project management, electrical and concrete work. LEED/sustainable design features incorporated into this project included energy-efficient lighting, plumbing and mechanical equipment. Antiterrorism force protection features incorporated into this project included seismic and structural upgrades to augment and enhance the building’s ability to support the eight aboveground floors.

This logistically challenging project required extensive planning due to limited access to the basement for deliveries of supplies, materials, equipment and personal. All deliveries were coordinated and scheduled well in advance so appropriate security background checks could be performed.

Construction activities required advance planning in creating a plan for construction, large structural steel members, some weighing as much as 10,000 lbs, needed to be moved into the building and installed with very restricted access. Original plans called for existing HVAC ductwork to be removed and replaced upon removal of ceilings. It was determined that 70% more ductwork existed than what was shown on the drawings and it was also shown as aluminum instead of steel. Stronghold was able to propose deletion or change of scope of some of the other features of work which allowed for the existing ductwork system to be removed and replaced with a current steel duct work system, saving both dollars and mitigating schedule slippage.


“From the get-go, you and your team have partnered with us on this technically and logistically challenging program and carried out construction in a fully-occupied and one of the largest hazardous abatement and life safety renovation projects in Southern California.”

Patricia Chang-Lynn, AIA Branch Chief/Project Executive