Following the Eastern Star

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A building that sits vacant for decades is a target. Graffiti, broken windows, rodent infestation, roof leaks, and sun deterioration all attack it until it becomes a blight in the cityscape. If that building is an unreinforced brick masonry structure in seismic country, the odds of that building making a comeback are slim. Such was the case for the Eastern Star Hall in Sacramento, California. Thankfully the Eastern Star Hall's listing on the National Historic Register improved its chances of survival.

The Order of the Eastern Star is an international organization that involves women in the Masonic Order. It was established in 1850 by Master Mason Dr. Rob Morris whose mission was to share Masonic principles with women. The first chapter in Sacramento, CA, was formed in 1879. The Order began to grow quickly such that by the 1920s there were five chapters in Sacramento. Scheduling events among the five chapters within the existing facilities at the Masonic Lodges proved challenging, so the Order of the Eastern Star held fundraising events to construct a new building. Local firm Coffman, Sahlberg, and Stafford Architects designed the Eastern Star Hall in the Classical Revival style, and it was built by the Masons themselves in 1928.

By the end of the 20th century, as membership in the Order was declining, the building went unused. They tried renting out the building to non-Masonic organizations, however the age of the building and resulting code violations, such as the lack of an elevator, eventually prevented its further use. By 1992, the Eastern Star Hall was the only surviving building out of four in the United States that were built specifically for the Order of the Eastern Star. The building was vacant for roughly two decades.

Hume Development purchased the property in 2018 with a preservation-forward focus. Their vision to preserve the main facade, the entry lobby with its staircase, the portion of auditorium floor above the lobby, and the east and west brick walls for the full length of the building would bring a contemporary and much-needed revitalization of the property. Although foundation settlement had caused cracking in the brick walls and the auditorium floor to be out of level, the finishes were in fairly good condition. The interior lodge rooms and most of the auditorium would be demolished and replaced with an eight-story, 128-room hotel while still retaining the original character and charm that the public once knew. Therein lies the intriguing structural challenge of demolition and reconstruction amid constraints of existing elements on a tight downtown site.

With a footprint of 70 feet by 145 feet and an exterior wall height of 62 feet, the original building looks more like a five-story building even though it is only three stories. From the main entry lobby, a grand staircase wraps around each side of the atrium as it guides visitors up to either the main lodge rooms or to the third-floor auditorium 30 feet above the lobby. The two main lodge rooms are 60-foot square and boast ceiling heights of 20 feet. The auditorium features stadium seating at the south and a stage at the north, with 10-foot-deep steel angle roof trusses above that clear-span the building, providing a large open ballroom for special events. The building also has a full basement complete with a kitchen and stage used for banquet events.

The lobby with adjacent lounge rooms extends 36-feet from the main entry facade. Additional lounge room mezzanines are halfway up the staircase. The existing structure comprised wood solid sawn floor joists supported by steel wide-flange girders and columns on shallow foundations. The exterior unreinforced masonry (URM) shear walls are largely non-load bearing due to the embedded steel columns within the walls.

While the construction materials of the original building are common among structures of this era, the unique geometry and layout of the interior spaces sets the stage for the complex conversion that revitalized the building.

Achieving Hume Development’s vision proved to be a formidable task. The most challenging aspect of the project was the sequencing of demolition and reconstruction. An approach to stabilize the three facades and the lobby with its staircase was developed using a bracing system installed on the interior of the building; external bracing was not feasible due to the close proximity of adjacent buildings. The internal bracing was designed using loading criteria from American Society of Civil Engineers (ASCE) 37 Design Loads on Structures During Construction. It was carefully woven into the existing structure so that it did not inhibit the removal of the existing structure while also staying out of the way of future permanent construction.

The predominant bracing for the east and west exterior walls involved a series of vertical steel trusses cantilevered from the foundation and spaced at about 16 feet on-center. The trusses integrated the existing W10 steel columns that were buried in the URM walls and one level of interior columns as the chords of the trusses. Additional columns were spliced onto the interior columns and interlaced with steel HSS diagonal braces. The bracing trusses were supported on existing exterior wall footings and new micropiles at the interior columns. Each individual piece of the bracing truss was located with an eye toward the future new construction so that it did not prevent installation of the final structural system.

The bracing at the existing lobby area required a different solution because a portion of the existing auditorium floor and the lounges below were to remain. The URM walls extended another 30 feet above the auditorium floor to the highest gable end peak. These were braced by adding two temporary levels of wood diaphragms above the existing auditorium floor. The diaphragms spanned to URM return walls or to temporary steel braced frames. Diagonal wood kicker braces stabilized the gable end walls down to the temporary floor. Additionally, the upper temporary floor had a waterproofing layer installed to help keep rainwater off the existing lobby finishes below.

Installation and removal of all temporary elements were coordinated in tandem with the new structural elements. Where a temporary element passed through the new structural floor, it was treated as an opening in the floor and subsequently patched back after removal of the bracing. The only location where a new gravity beam conflicted with the bracing system was where the floor deck was vertically shored with temporary stud walls to complete the floor diaphragm and thereby brace the existing walls. Only then was the bracing system deconstructed and the final beam inserted to support the floor.

The new 86,000 square foot structure for the eight-story hotel consisted of concrete-over-metal-deck floors with steel beams and columns supported on a mat slab foundation. The steel beams were aligned with guestroom demising walls and corridor walls to implement 10-foot floor-to-floor heights. This system was inserted into the shell of the perimeter URM walls and enveloped the existing lobby at floors five through eight.

A mat slab foundation 28-inches-thick was installed at the existing basement level. The mat slab was analyzed using CSI SAFE which provided demands at the interface with the existing URM wall footing along the perimeter. This interface was evaluated and detailed with epoxy dowels to consider the mat and the wall footing as integral members. The new lateral system consisted of buckling-restrained braced frames tucked into corners and tightly placed along edges of the building. Where the braced frame columns landed on the existing wall footing, that portion of the footing was cut out and replaced with a new reinforced grade beam element within the mat slab. This was especially important at the corner columns to ensure that the frame column was properly supported by the mat.

The new lateral system serves as the primary lateral support for the existing structure. The 2016 California Building Code (CBC) governed design of all new systems, however the 2016 California Existing Building Code - Appendix A1 (CEBC) was used to evaluate the out-of-plane capability of the existing URM walls. These walls spanned the short 10-foot floor-to-floor distance where the concrete diaphragms delivered out-of-plane loads to steel buckling-restrained braced frames. The three-wythe URM walls easily met the height-to-thickness ratios of the CEBC. For loading parallel to the URM walls, the connection to the floor was detailed to allow movement of the floor relative to the wall such that the wall was decoupled from in-plane lateral forces of the new structure and only resisted its own inertial seismic loads. This was achieved by wrapping foam on the epoxy rebar dowel tension ties so that they had room to flex in-plane for the expected building drifts.

Two shotcrete shear walls were placed against the primary URM entry facade with cutouts where the existing windows occurred. The purpose of these shotcrete walls was two-fold: to support gravity loads from the new fifth-floor framing as it extended over the top of the existing lobby, as well as to provide in-plane shear resistance for the main facade. Since the new steel lateral system was decoupled from the perimeter URM walls, special care was taken at this level. The interface of the fifth floor to the existing URM wall included a seismic joint with slide bearings to allow the perimeter walls to only resist their own in-plane inertial loads, while out-of-plane loads were supported by the new concrete diaphragm. The new concrete walls rested on a pair of micropiles at each end and included pile caps detailed to underpin the existing facade wall to mitigate settlement that had opened up a 2-inch crack between the lobby area and the northern portion of the building.

Anchoring into the URM walls was achieved using drill and epoxy bolts or rebar. Concrete elements such as shear walls utilized epoxy rebar dowels while steel elements utilized threaded bolts. Capacities for the anchors were taken from the ICC code report for the epoxy system since most of the URM walls in the building were three-wythes in thickness as the code report requires. However, some anchors were required in the two-wythe former parapet of the east and west walls. For these instances, a project-specific anchor testing program was performed by pull-testing anchors installed in a portion of the parapet that was ultimately slated for demolition to justify usage of epoxy anchors in the 8-inch URM.

Keeping the eight stories below the CBC high-rise floor limit of 75 feet required that the new third floor be set 16 inches lower than the existing third floor level. Due to space constraints in the guestroom layout, it was determined that the recess to accommodate a wheelchair lift and stairs connecting the existing level to the new level needed to occur within the existing framing. This recess required about 10 inches of an existing 16-inch steel beam be cut out. The beam was strengthened by adding a new wide-flange beam welded to the underside that extended beyond the cutout portion to connect the existing beam to its supporting girder.

The hotel welcomed its first guests in January 2023. Visitors can enjoy the renovated lobby and learn about the Order of the Eastern Star and Sacramento history in the reading room adjacent to the lobby. The guestrooms include a kitchenette and workstation which are attractive to those who need a longer-term stay option, perhaps when visiting patients at nearby Sutter Medical Center. The third-floor bar is open to the public to enjoy the character of this unique building. The Eastern Star Hall is once again thriving in the community thanks to the vision of the development and design teams. ■