6712 Hollywood Blvd. Los Angeles, CA 90028 | map |
The Egyptian Theatre pages: an overview | Hollywood Blvd. views 1922-1954 | Hollywood Blvd. 1955-present | forecourt | lobby - earlier views | lobby - recent views | auditorium - earlier views | auditorium - recent views | booth | backstage | Egyptian 2 & 3 | along Las Palmas Ave. | along McCadden Place | structural + 2021 renderings |
The Egyptian at the 2024 California Preservation Conference
The theatre's renovation by Netflix was the topic for a May 30, 2024 presentation at the Biltmore as part of that year's California Preservation Conference. Theatre historian Mike Hume kicked off the session and introduced the principal architect for the project, Ross Brennan of Studio 440.
Melineh Zommorrodian, the lead structural engineer for the renovations, followed with a presentation about the challenges presented by the 100 year old theatre. She's with
the Gardena-based firm Structural Focus. Mel began by outlining the 2015 City of Los Angeles requirements for a mandatory retrofit of non-ductile concrete buildings designed prior to adoption of the 1976 Uniform Building Code. Qualified historic buildings are categorized separately and must comply with the California Historical Building Code.
The scope of work at the Egyptian included a full seismic retrofit to meet CHBC, a "Rewind Rehab" to remove the 1998 additions and fully restore the building to original conditions, and upgrades to modernize the theatrical systems.
A testing program was initiated to determine the properties of the concrete in beams, columns and roof diaphragm.
Sections of reinforcing steel bars were removed for testing.
Hollow clay tile was removed from exterior walls.
The dark brown indicates areas of HCT tile that were removed in the project and replaced by steel stud walls. Light brown shows tile areas that were replaced by concrete. The yellow areas are sections that had already been filled with concrete during the 1997 renovations.
Tile removal on the west wall.
East wall tile removal in progress.
Cornice repair. Click on any of these for a larger view.
Cornice repair details.
New shear walls. On the left we're upstage right. In the right image we're back under the projection booth overhang looking through the auditorium to the back wall of the stagehouse.
New shear walls. In this shot from the 1997 renovations note the visibility of the back of the plaster of the auditorium side wall.
The historic plaster areas were temporarily shored and a waterproof membrane added before new shear wall sections were poured.
Shear wall work on the east wall with details of typical rebar installation at columns and beams.
New foundation work under the east wall.
New foundations at the theatre entrance. At the right we're out in the forecourt. At the left side of the image it's the columns of the north exterior wall behind the restrooms.
More foundation work.
Strengthening of the roof diaphragm.
Diaphragm strengthening - plan view.
Diaphragm strengthening.
Column deformation compatibility.
Column deformation compatibility. Both views are looking to house right in the part of the lobby that was originally the rear of the seating area. On the left the new floor had been poured and the area was scaffolded for ceiling plaster repair.
Upgrading the historic ceiling bracing.
A section view of added bracing for the lobby ceiling. The box at the left is the new control room at the back of the auditorium's seating area.
Ceiling bracing in the lobby.
Concrete repair. In the center images we're offstage left, looking into the auditorium. The image on the right is outside on the McCadden Place side of the building, looking up at what had been the 2nd and 3rd floors of the dressing room area.
Proscenium beam repair. On the left is a view from the 1922 plans with the areas noted in green being the columns and beam that were removed during the 1968 D-150 renovations. While trade magazine stories noted that a new concrete beam was poured, there was nothing evident from visual inspection and no documentation was found. The area was shored pending upgrades to the structure.
A closer look at the proscenium plan.
Proscenium beam repair. The solution was to augment a column at either side of the stagehouse and pour a new 3' x 7' beam under the grid spanning the full width of the stagehouse to support the grid, roof, and organ loft. You can click on the image for a larger view.
Proscenium beam repair. On the left we're on the east side of the building with the stagehouse at the left and the auditorium sidewall at the right. The black-wrapped column is the one on this side that was augmented to carry the load of the new proscenium beam. On the right it's a view of the new proscenium beam and the columns on each side of the stagehouse. The light colored area this side of the decorative ceiling is the bottom of the organ loft.
Thanks, Mel!
"STRUCTURE" - January 2025
The structural issues arising during the Netflix renovations were discussed in "Unveiling Secrets," a six
page article by Jonathan Lehmer, SE, and Melineh Zommorrodian, SE, of
the firm Structural Focus that appeared in the
January 2025 issue of the magazine "Structure." It's excerpted here. See a page on the Structure website for the full article as
well as a link for downloading a PDF of the complete issue.
On the Cover: The seismic retrofit of the historic Egyptian Theatre in Los Angeles, which hosted the world’s first red carpet premiere, serves as a model for balancing modern engineering demands with the preservation of architectural heritage.
Image courtesy of Mike Hume at historictheatrephotos.com.
The Theatre is a mostly single-story building with an attached three-story portion at the southwest corner. The building is approximately 200 feet long, 130 feet wide, and 64 feet tall. The concrete roof structure is multi-tiered and supported by a series of concrete trusses to create an unobstructed interior with minimal interior columns. Concrete beam and column frames form the perimeter walls and all columns are generally supported on spread footings (Fig. 1).
The Theatre received several renovations and changes over the years, including modification of the proscenium (the dividing line between the stage and auditorium) structure to increase the viewable stage width for a wide projection screen and a renovation and voluntary seismic retrofit in 1997/1998 following significant damage from the 1994 Northridge earthquake.
City of Los Angeles Retrofit Ordinance Strong earthquakes have caused severe damage to concrete buildings designed and constructed without ductile detailing requirements implemented in the 1976 Los Angeles City Building Code, or similar codes from that period. The City of Los Angeles implemented an ordinance that required the compliance, retrofit, or demolition of concrete buildings permitted before January 1977 within city limits, with exceptions for detached single-family dwellings or detached duplexes. The prior 1997/1998 voluntary seismic retrofit of the Theatre was determined to be inadequate for the requirements of this ordinance. The team proceeded with an ASCE 41 approach to meet the ordinance requirements.
Material Testing and Condition Assessment The design team located detailed original architectural and structural drawings of the Theatre and the structural drawings of the previous voluntary retrofit which were invaluable. However, despite having the detailed drawings, a major challenge faced at the project's start was the lack of material properties in the original documents. A material testing program was prepared... to obtain the concrete and reinforcing strength of the original construction.... A total of 72 concrete cores and 15 rebar samples were tested... The condition assessment verified the accuracy of the construction documents and found limited concrete damage and cracking which was not unexpected for a 100-year-old structure.
Project Retrofit Scope Structural Focus’ experience with seismic retrofits of similar non-ductile concrete buildings informed the decision to avoid using any of the existing non-ductile concrete frame system as a vertical lateral force resisting system. A proposed seismic retrofit system of new concrete shear walls was developed, and the behavior of the building with the proposed seismic retrofit upgrades was analyzed in ETABS using a linear dynamic response-spectrum-based modal analysis procedure (Fig. 2).
... To create diaphragm continuity across the various roof elevations, new concrete diaphragm transfer walls were designed as deformation-controlled elements to avoid adding interior shear walls that would interrupt the auditorium area. Utilizing the analysis results from the linear dynamic model, the shear and flexural strengths of the existing concrete diaphragms were analyzed... While the flexural strengths were sufficient, the existing shear strength of the lightly reinforced 3-inch-thick diaphragms was deficient adjacent to various shear wall lines. Fiber-reinforced polymer (FRP) diaphragm shear strengthening demands were determined per ASCE 41 as deformation-controlled actions and specified on the structural drawings for deferred submittal design (Fig. 3).
The diaphragm connections to the shear walls were then analyzed per ASCE 41 as force-controlled actions and found to be deficient. To mitigate the deficiencies, new collectors were designed to increase the shear transfer length with the addition of FRP between the diaphragm and collectors to increase the shear transfer strength (Fig. 2). The new collectors and FRP shear transfer strengthening were both designed as force-controlled actions... The retrofit design continued with the analysis of the new and previous retrofit concrete shear walls for in-plane shear and flexure as deformation-controlled elements per ASCE 41...
The existing columns and beams were analyzed for the appropriate out-of-plane loads where required and confirmed to be adequate without any added strengthening. Continuity of the shear walls for in-plane and out-of-plane demands through the existing concrete beams and columns was achieved by doweling rebar through the existing concrete members (Fig. 4).
The strength and shear friction transfer of these bars was critical for the intended shear wall behavior to act as single large wall panels per wall elevation. The design utilized large diameter bars for these dowels to reduce the number of drilled holes and the likelihood of hitting/damaging existing reinforcing bars in the existing concrete members...
The preservation and protection of the historic plaster finishes on the interior faces of the new exterior shear walls required careful consideration during the construction of the shotcrete walls. Avoiding damage to the historic plaster was of paramount importance for the project. The contractor, in coordination with the design team, elected to use small light gauge steel shaft studs to hold the backing for the shotcrete wall along with the waterproofing membrane (Fig. 5). The shaft studs were buried inside the shotcrete wall without interrupting the continuity of the reinforcing.
The existing building foundations are at different elevations throughout the site, and at some locations, they are +/- 15 feet below grade. To avoid surcharging or undermining the existing foundations, the bottoms of the new and existing foundations were aligned in the structural drawings. This proved challenging during construction due to the required depth of excavations, adjacent property lines, adjacent building surcharges, and steps needed in the new foundations to accommodate elevation changes. Due to the project schedule, rebar shop drawings were produced based on the original drawings and fabrication began prior to excavation. Adjustments were made in the field as existing foundations were exposed and found to deviate from the original drawings, causing rebar congestion and step layout issues (Fig. 6).
The independent gravity columns of the Theatre that were not integrated into new concrete shear walls were analyzed as deformation controlled secondary members according to ASCE 41 for seismic drift compatibility. The analysis revealed that the independent columns had inadequate shear strength to develop the full expected plastic flexural capacity of the columns and were classified as shear-critical. To strengthen the columns to achieve a flexure-critical condition, the required FRP shear strengthening to develop the full expected plastic flexural capacity was specified on the structural drawings as equivalent grade 60 shear reinforcing along with the existing material strengths and the classification of the member action for deferred submittal design (Fig. 7).
Project Renovations Scope Major renovations to the Theatre were included in the project with the goal of enhancing the audio and visual capabilities and user experience to achieve a state-of-the-art movie experience similar to other modern theaters. Additionally, in collaboration with the historical preservation architect Historic Resources Group, the design team was driven to further reveal and highlight the original architecture of this grand movie palace.
Although the original Theatre design did not include a lobby area, the new architectural layout required one that would also host a control booth. A new steel framed platform for these functions was designed to visually and acoustically separate the non-enclosed entry from the auditorium. Below the lobby platform a new concrete partial basement provides the necessary area for an emergency generator and mechanical equipment. A new light gauge steel framed projection booth on the low roof is accessed by elevator from the lobby and is capable of projecting modern movie formats and nitrate film formats (one of only five nitrate film projection theaters in the United States).
Various stage improvements utilizing conventional steel and light gauge steel framing provide the infrastructure for presentations and for the large projection screen. Steel tension cable supported speakers in the auditorium provide high quality Dolby Atmos audio and a new auditorium seating platform constructed of tiered raised access floor systems leads from the lobby platform down to the stage. Finally, a new steel stair and catwalk provides access to the fly loft and original organ loft from inside the three-story structure at the southwest corner of the Theatre.
A defining feature of both the 1997/1998 renovations and the new renovations is the design for “reversibility.” Reversibility is characterized as features designed for the possibility of future removal without negatively impacting the original features and structural stability of a building. Its applicability extends to architecture, mechanical, electrical, plumbing, structural, and all other renovation features of a building. This design feature is especially important for historic structures to avoid unnecessarily impacting historic fabric and to allow the structure to undergo future renovations without significantly altering the historic structure. The design team collaborated so the new renovations are designed to be either standalone without tying into the core and shell structure, or removable without negatively impacting the structural strength of the core and shell structure like the cantilever partition walls around the new lobby, or the tension cables supporting the speakers.
Hidden Conditions and Damage During construction, despite the initial findings of the visual condition assessment during design, after the removal of all the exterior plaster finishes widespread poor-quality concrete and damage was found. Poor quality concrete consisted of inadequate consolidation, rock pockets, honeycombing, and inadequate reinforcement clear cover. Damaged concrete consisted of cracking, reinforcement corrosion, spalling, and delamination. The cracked concrete is likely partially due to damage during the Northridge earthquake and other regional earthquakes. A repair program was enacted to rectify these structural issues encountered since the full design strength of many of the original elements was necessary for the retrofit (Fig. 8).
A defining feature of both the 1997/1998 renovations and the new renovations is the design for “reversibility.” Reversibility is characterized as features designed for the possibility of future removal without negatively impacting the original features and structural stability of a building. Its applicability extends to architecture, mechanical, electrical, plumbing, structural, and all other renovation features of a building. This design feature is especially important for historic structures to avoid unnecessarily impacting historic fabric and to allow the structure to undergo future renovations without significantly altering the historic structure. The design team collaborated so the new renovations are designed to be either standalone without tying into the core and shell structure, or removable without negatively impacting the structural strength of the core and shell structure like the cantilever partition walls around the new lobby, or the tension cables supporting the speakers.
Hidden Conditions and Damage During construction, despite the initial findings of the visual condition assessment during design, after the removal of all the exterior plaster finishes widespread poor-quality concrete and damage was found. Poor quality concrete consisted of inadequate consolidation, rock pockets, honeycombing, and inadequate reinforcement clear cover. Damaged concrete consisted of cracking, reinforcement corrosion, spalling, and delamination. The cracked concrete is likely partially due to damage during the Northridge earthquake and other regional earthquakes. A repair program was enacted to rectify these structural issues encountered since the full design strength of many of the original elements was necessary for the retrofit (Fig. 8).
During the early phases of the design, it was noted that the original proscenium columns on each side of the stage did not exist, and no documentation of this modification could be found. The original proscenium was designed with a narrow view of the screen, and it is likely that as movie projecting technology progressed, the desire for a wider screen resulted in the widening of the proscenium. As construction commenced and finishes were removed, it was alarmingly discovered that the columns had been demolished without adequately modifying the structure of the roof to increase the proscenium girder span from the original approximately 42 feet to the modified approximately 70 feet. Considering the tributary roof areas loading the proscenium girder line consisted of the high roof over the stage, the organ loft roof, and the organ loft floor slab, large shoring towers to support the deficient proscenium girder were installed.
A new large concrete girder was designed to support the tributary roof and organ loft loads and span approximately 70 feet between the perimeter columns. The original perimeter columns that now supported the new girder were analyzed for the increased load and found to be deficient for confinement and concrete area. Since the columns could only be enlarged towards the interior to avoid changing the exterior historic features of the Theatre, the requirements for added confinement were designed as additional FRP strengthening and the equivalent grade 60 confinement reinforcing was specified on the structural drawings for deferred submittal (Fig. 9).
During construction, it was also discovered that an undocumented sloping concrete topping slab had been previously added on the original low roof of the Theatre over the new lobby area. In some areas the topping slab was up to 12 inches thick and significantly increased the weight of the low roof compared to the original 3-inch slab. Since the weight of the topping slab was not considered in the retrofit design already under construction, as well as the requirements for installing FRP directly on the structural roof diaphragm slab, the topping slab was selected to be removed. Removal was time consuming and required care to be taken to avoid damaging the structural roof diaphragm slab because the topping slab was found to consist of hard rock concrete that was well bonded to the 3-inch slab.
Conclusion The comprehensive retrofit and rehabilitation of the historic Egyptian Theatre in Hollywood stands as a remarkable example of how engineering innovation can merge with historical preservation and modern renovations to achieve seismic resilience and the successful re-birth of a landmark historic building. By adhering to the rigorous requirements of the City of Los Angeles’ mandatory retrofit ordinance, the project successfully navigated the complexities of retrofitting a non-ductile concrete (NDC) structure without compromising its historical integrity. Through the strategic use of fiber-reinforced polymer (FRP) and traditional strengthening techniques, the Theatre was fortified to meet modern seismic demands while preserving its iconic architectural elements. Moreover, the careful bracing of historic elements like the historical plaster ceiling and the reinforcement of the proscenium girder illustrated the commitment to maintaining the Theatre's historical character while upgrading its structural performance.
About the Authors: Jonathan Lehmer, SE, is a project engineer at Structural Focus in Gardena, CA. His project experience ranges from new high rise to retrofit and rehabilitation and historic preservation. Melineh Zomorrodian, SE, joined Structural Focus in 2008 as an intern, and remained with the firm following her Masters graduation from UCLA. She specializes in structural analysis, design, and construction administration.
Conclusion The comprehensive retrofit and rehabilitation of the historic Egyptian Theatre in Hollywood stands as a remarkable example of how engineering innovation can merge with historical preservation and modern renovations to achieve seismic resilience and the successful re-birth of a landmark historic building. By adhering to the rigorous requirements of the City of Los Angeles’ mandatory retrofit ordinance, the project successfully navigated the complexities of retrofitting a non-ductile concrete (NDC) structure without compromising its historical integrity. Through the strategic use of fiber-reinforced polymer (FRP) and traditional strengthening techniques, the Theatre was fortified to meet modern seismic demands while preserving its iconic architectural elements. Moreover, the careful bracing of historic elements like the historical plaster ceiling and the reinforcement of the proscenium girder illustrated the commitment to maintaining the Theatre's historical character while upgrading its structural performance.
About the Authors: Jonathan Lehmer, SE, is a project engineer at Structural Focus in Gardena, CA. His project experience ranges from new high rise to retrofit and rehabilitation and historic preservation. Melineh Zomorrodian, SE, joined Structural Focus in 2008 as an intern, and remained with the firm following her Masters graduation from UCLA. She specializes in structural analysis, design, and construction administration.
2021 Renderings of the Netflix project:
A rendering of the revamped forecourt design by project architects Studio 440 Architecture and Acoustics. It appeared with the presentation for the January 7, 2021 meeting of the City's Cultural Heritage Commission. Among
other work on the multi-million dollar project, the lobby was
redesigned, the balcony was removed, the building got a seismic retrofit and the small Spielberg Theatre vanished.
Ross Brennan is the lead architect for Studio 440. Peyton Hall of Historic Resources Group was the project's historic consultant. Others on the team included
Structural Focus as the structural consultant, Syska was the MEP
consulting engineer, Sightline Design Group was the lighting designer,
Venekklasen Associates was a noise and vibration consultant, Silverlake
Conservation was the architectural conservator, Visioneering Design Co.
and David Carroll Associates were system integrators.
All the renderings appear courtesy of Netflix. Thanks to Dean Boerner for including seven of the renderings with "Netflix Unveils Plans...," his December 30, 2020 post on the site What Now Los Angeles.
The
rear of the auditorium. This rendering was also included in the
presentation Netflix made to the City's Cultural Heritage Commission on
January 7, 2021.
A floorplan from Studio 440 that was part of the Netflix presentation on January 7, 2021. The curved row of columns in the middle of the beige lobby area is where the seating area ended in 1922. The
visuals for the initial presentation before the Cultural
Heritage Commission are available as a 40 page PDF under "PowerPoint
Presentations" in a 1/7/21 Google Drive folder.
The
second version of the proscenium. In response to comments made by the
commissioners at the January 7 meeting it was made slightly more
elaborate. Note the addition of sets of double columns on either side of
the screen where there had earlier been boxier, darker, pilasters. Also
added was a sunburst design in the formerly blank panel above the exits
from the stage. This rendering was prepared for a presentation at the
Cultural Heritage
Commission's April 15 meeting.
A look at the proposed hanging method for the Atmos speakers. It's another rendering prepared for the April 15, 2021 meeting. In
addition to the proscenium and speaker discussions, other topics
included auditorium wall colors, the building's seismic retrofit and
various signage changes. A copy
of the visuals for that presentation is available as a PDF under "PowerPoint Presentations" in a 4/15/21 Google Drive folder. Cultural Heritage Meeting agendas are available via this meeting list.
Pages about the Egyptian: an overview | Hollywood Blvd. views 1922-1954 | Hollywood Blvd. 1955-present | forecourt | lobby - earlier views | lobby - recent views | auditorium - earlier views | auditorium - recent views | booth | backstage | Egyptian 2 & 3 | along Las Palmas Ave. | along McCadden Place | back to top: structural + 2021 renderings |
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