CS 2. Case Study. Grounded in strength.

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1 Payson Utah LDS Temple CS 2 Case Study Grounded in strength.

2 Forterra Structural & Specialty Products Classic, Ornate Design Sculpted In Architectural Precast Project Description Bright and sparkling, with a delicately-detailed architectural precast exterior, the new Payson Temple for the Church of Jesus Christ of Latter-day Saints is purposefully designed to be inspirational. The four-story structure is capped by a 212-ft-tall central, tiered steeple. High atop this spire is a gold-leafed statue of the Angel Moroni with trumpet in hand ready to proclaim the good news of the gospel. In the background is a magnificent view of Utah s Wasatch mountain range. As the latest temple for the Church of Jesus Christ of Latter-day Saints, the Payson, Utah, building will serve and inspire a projected 78,000 church members. The new 96,630 ft 2 structure consists of a cast-in-place concrete foundation and sub-basement, topped by a steel-framed main building supporting highly detailed architectural precast concrete panels from Forterra. Also precast-cladded, the building s steelframed steeple features art glass, a dome and the Angel Moroni statue. Design based on historic motifs The intricate building design ornate both inside and out was the result of extensive collaboration between Architectural Nexus and the LDS Church s Special Projects Department. The building owners had in mind a specific aesthetic with an historic flavor, explains David Fletcher, principal in charge for Architectural Nexus. We started with the floor plan of a previously built, precast temple and made some major modifications. We tried to maintain continuity in the interior and exterior functionality of the two structures, yet the two buildings are very, very different in appearance and aesthetic. The intent for the new structure was to capture some of the pioneer flavor of the Payson area, continues Fletcher. We were asked to research the traditions and historic buildings of the area to determine design elements that pertained to the local culture. For example, if you look closely at the new building there are references to classical quilting motifs that had been popular in the Payson pioneer era. Such elements are reflected in the classical entablature detailing and bas-reliefs on the upper, precast portions forterrabp.com

3 Project Type: Religious temple Location: Payson, Utah Owner: The Church of Jesus Christ of Latter-Day Saints (LDS) Architect: Architectural Nexus, Salt Lake City, Utah Structural Engineer: Reaveley Engineers + Associates, Salt Lake City, Utah Contractor: Wadman Corp., Odgen, Utah Precaster: Forterra Structural & Specialty Products, Mountain Region, Salt Lake City, Utah, facility Precast Products: Architectural precast panels and pieces Completed: February, 2015 of the building. Payson also has a long heritage as a fruit growing area, so an apple blossom and vine motif is one of the elements executed, primarily, in the building s decorative art glass. While these motifs are expressed in the exterior of the building in architectural precast, a lot of the same or related details are executed in fine wood millwork and cast metal on the building interior. Apple leaf patterns, for example, show up in the cast metal railings on the major staircase on the main floor. The building s ornate interior also features marble and natural stone trim and accents, as well as flanking canopies at the entrance, dramatic floor-to-ceiling windows and colored art glass. Creating ornate details in precast With the amount and level of intricate detail demanded, I think the Payson Temple pushed the capabilities of precast, says Fletcher. Forterra was brought in quite early and we worked very, very closely with them to develop ways that these design elements could be done in precast. Forterra first created mock-ups of these details to see that they would work, then created forms into which the architectural precast pieces could be cast. This was a tedious job. It took not just craftsman but artisans to create these sculpted form work pieces. Creating such a huge variety of finely detailed precast panels was, indeed, a major challenge, agrees Jim McGuire, sales manager for Forterra s Salt Lake City, Utah, facility. We had radiused pieces that went above entryways and at every level. There were dome pieces that were elliptical shaped, corner pieces with chiseled rope detail, cornices, walls, detailed columns, signs, site walls at planters, and a cornerstone, says McGuire. In all, the project required 1,615 individual precast concrete pieces totaling 116,876 ft2. To demonstrate the complexity of the precast panel production process, McGuire points to the actual production drawings for just one of the radius panels. The drawings consist of five pages covering the dimension, shape, radius, reinforcing and handling of that single piece. To produce the complex precast pieces, Forterra used casting forms made of wood, plastic, rubber, foam and/or plaster. Highdensity plywood forms were used for the majority of the pieces. Foam, cut with a three-dimensional cutter, was used on irregular shapes. Forms for more intricate shapes, such as medallions and the chiseled rope effect, were custom made out of rubber.

4 Many of the radiused forms were so large and complex that they took multiple weeks to build. Some took 12 to 13 weeks to build. A supplier crafted the original detail shapes out of ceramic, then cast rubber negatives of them for the forms. Plaster and plastic were also used to form up different steps, edges and angles in the various precast pieces. Custom concrete mix, tight QC Exterior walls of the temple, itself, consist of conventional architectural precast panels. To reduce weight on the massive building steeple, Forterra utilized thin-shell precast panels made with glass fiber reinforced concrete (GFRC) for this portion of the structure. Forterra used a self-compacting concrete so that it would flow into all the nooks and crannies of the complex forms, prevent bug holes and air pockets and show all the ornate detail on the face of the panel. Part of the challenge, says McGuire, was to find the right look for the client. We tried different aggregates from all over the country and chose an aggregate from Salinas, California. The concrete used is a custom mix with white cement, white sand and white aggregate with sparkle and a little bit of pigment in it. The desire was that the building be sparkly when the sun shines on it. It definitely has that look. The precast panels have a sandblast finish. This required very tight control on the sand blasting so that when the different panels were erected side-by-side the surfaces would match up and blend together. The panels were produced during winter, so the sandblasting operation had to be done indoors to control the environment and produce a uniform effect. Another design goal was to minimize the number of visible joints, adds McGuire. To achieve this goal, corner precast panels were designed with deep, four foot returns in each direction around the corner. In short, wall panels stop short of the building corners and L-shaped precast panels cover the corners like corner moldings on wood trim. Explains McGuire: At the corner you have a flat wall panel coming in from both directions and, instead of having them come together at the corner to form a visible joint, we have an L shaped panel in the corner. Where the corner and wall panels meet appears as a vertical architectural reveal feature even though it is actually a panel joint. To ensure that both faces of the corner panels would be uniform, Forterra set the forms in a V-shape for pouring rather than having one face poured flat and the other poured vertically. This allowed the concrete to consolidate on both faces at the same forterrabp.com

5 time. Greatly complicating the production process was the fact that the design of the corner panels included the chiseled, woven or braided rope detail. We had to be extremely careful with the sandblasting, says McGuire, so as to get the correct exposure but not blast the edges off the features. Fitting pieces together seamlessly Precast connections were also a major challenge. It was like fitting together a three dimensional jigsaw puzzle, McGuire explains. The first challenge is to get the pieces to fit together. For this, the form work and the quality control had to be very carefully done, and the shapes had to be erected in order. The second challenge was that the precast pieces also had to fit with the structural steel behind them. There were cases where the tolerances were a bit off but we were able to adjust things to make them fit. Erection was done with all welded connections to the steel structural frame. Where there were shear walls, pockets were provided in them for the connections. For seismic force resistance, the temple structure incorporates cast-in-place concrete shear walls that, in some places, run the full height of the building. The building s two elevator shafts are constructed of concrete masonry units. Floors and roof consist of a composite metal deck and concrete system on steel framing. Using this system for the roof allowed forces from the steeple tower to be transferred laterally into perimeter structural elements, such as the shear walls, to provide seismic resistance. Foam insulation was spray-applied in place to the backside of the precast wall panels at steel framed locations. Rigid board insulation was placed on the outside surface of the cast-in-place-concrete perimeter shear walls before the architectural precast was hung. The project includes a sophisticated, highly efficient hot water heating/chilled water fan-coil air system. A small, precast ancillary building houses boilers and chillers and is designed to complement the design of the temple. Set on a rural, acre site, the temple is surrounded by parking spaces for 800 cars, planting islands, decorative lamp posts, wrought iron fencing, a water feature and extensive landscaping with trees, shrubs and flowers. Storm water is collected on site, transported by surface flow and piping into an underground system that allows it to dissipate into the ground.

6 Advantages of using precast construction Architectural precast was chosen for the Payson Temple for several reasons, according to Architect Fletcher. For one, LDS church officials like the feeling of permanence in a building, Fletcher says. Most temples are constructed either in stone or precast concrete. Precast has a lot of the same qualities and feeling of permanence that stone has, but usually has a significant cost advantage. Another advantage and a major advantage is that [with precast] the walls erect quickly which allows the interior finish work to start sooner than it might on other types of construction, Fletcher adds. When you have a precast building, the building takes shape very early in the process. It goes together relatively quickly. On the Payson temple, we were able to install [interior] finishes on the lower floors while they were still applying exterior cladding on the upper floors. Ground was broken for the new temple on October The temple construction is scheduled to be completed by the first of February and dedicated in June of this year. Erection of the complex architectural precast cladding took less than eight months. forterrabp.com 21231/CS2/Spectrum/7.16/R