Featured Projects

How Masonry Fulfilled the Green Wishes of the Choctaw

If anyone in the South knows about the sanctity of its land, it’s the Choctaw.

Of the 40 million acres that make up Mississippi, they once had dominion over 11 million of them.

And if anyone in the South knows about the the fundamental obligation we have to sustain it, it’s the Choctaw.

For hundreds of years they would name their families after the animals and nature that shared that great big stretch of land along with them. The bear. The deer. The wolf. The holly leaf. The panther. Even the wind.

That’s why recently, when the leaders of their sovereign nation known as the Mississippi Band of Choctaw Indians — currently one of the largest employers in the state thanks to the Golden Moon Casino, the Silver Star Casino and 17 other businesses — wanted a major addition to one of their communities’ elementary schools in Pearl River, sustainability wasn’t an option.

It was a must.

Enter Roger Pryor of PryorMorrow, an architecture firm based in Columbus, Mississippi, and NCMA member Saturn Materials.

“The environmental impact on the project was a priority,” said Roger Pryor, principal architect, AIA, NCARB. “The use of Saturn Materials concrete block as exterior cladding substantially reduced the environmental impact of the project.”

The Saturn Materials proprietary mix design has a nearly 70% reduction in the cradle-to-the-gate carbon footprint and meets the ASTM standards for the concrete industry.

“From the standpoint of operating this facility, and building it, they wanted the project to be fairly green. We were able to succeed in that both in the way we did the building envelope and also with the mechanical and electrical systems,” said Pryor.

“The exterior is all masonry. It’s a good sturdy building on the exterior as far as weather.”

As for an overarching theme to the design, both inside and out, the architects at PryorMorrow were determined to listen and stay genuinely faithful to the traditions of the tribe. Throughout the facility, important symbols and images are carefully displayed and presented in very authentic manner.

“Something that’s important to that tribe and important to the Bureau of Indian Affairs is that there be some cultural influences included in their projects,” said Pryor. “And I think that’s really important in this project because you go to a lot of places on Indian reservations and they tell designers to include cultural elements and it gets kind of Mickey Mouse and Disneyland-like, and the Native Americans are very sensitive about that. And rightfully so, obviously.

“We actually had a cultural committee that we worked with to make this project happen. And they had quite a bit of influence.”

One of the school’s most impressive and heralded features is an outdoor plaza.

“It’s sheltered and provides a lot of shade and it’s where the students congregate before school and after school as well eat lunch,” said Pryor.

“The canopy of the plaza is very important for a number of different reasons. First off, it’s where the kids can safely hang out. Second, it has a state-of-the-art audio system that amplifies Choctaw language as well as chants.

“The most important game that Choctaws play is a game called ‘stickball.’ The mallets they use in this traditional game served as the inspiration for the structural system that holds up the canopy.”

From the standpoint of security all entrances have electronic access control so you have the ability to lock the school down. And all of the teachers have the access code capability to come and go.

Each classroom has a special latching device at the door to protect kids in the case of an active shooter where it’s a double function locking mechanism.

“It’s a ‘cut above’ of what usually serves as a typical classroom building,” said Pryor.

Other key features seen throughout the building include Choctaw language on interior signage, round medallions over each classroom window that are inspired by the Choctaw beadwork and round view windows of each classroom door that mirror the exterior medallions.

The mountain imagery of the classrooms is inspired by Choctaw images. Interior murals at the focal points of corridors include a historic photograph from the Museum of the American Indian (Smithsonian) and contemporary Choctaw photographs of the tribe’s children.

The building also boasts all LED lighting and brand new state-of-the-art polyester carpeting.

“A proper education is one thing we strive to supply for our children. For years, we have struggled with limited space for our students here at Pearl River Elementary. We have long since outgrown the building that was built in 1990,” said Tribal Chief Cyrus Ben.

The school is currently open, operating and educating more than 600 students — exclusively from the Mississippi Band of Choctaw Indian community.

How CMU Allowed an Architect to Design One of the Five Safest Schools in America

“First and foremost they wanted something that was going to be timeless – a classic design. And they wanted something that was going to be secure for the students. Part of that is durability – the wear and tear on middle schools is pretty tough, so concrete block was a ‘no-brainer’ option.”

When architect Calvin Durham and his team at Lambert Ezell Durham Architecture in northern Alabama were tasked with designing the new middle school in their hometown of Florence, they knew right away that they could draw upon structures of the past.

The 180,000 square-foot space is a partial Tuscan ode — design-wise — to the former Appleby School, which opened in 1917 and was eventually replaced in 1951.

“We used some of that detailing and some of that ‘feel.’ We didn’t copy it so much as we used that same vernacular of elements to kind of draw back on,” Durham noted.

What he and none of his associates on the project expected however, was for one of the most renowned voices in the world on the subject of school safety to proclaim their new structure one of the most secure schools he’s ever encountered.

“I was blown away,” said Durham.

Michael Dorn, executive director at Safe Havens International, the world’s leading international nonprofit campus safety center, told Durham’s firm that of the 7,800 schools he’s reviewed, Florence is in the top five.

Finished in February 2019, the new educational facility  — which Durham admits often gets mistaken by onlookers as part of the nearby university, Northern Alabama — is secure for a number of reasons. Clear sight-lines, electronically-controlled public access are a few and part of the equation, but all of these are state-of-the-art technological features are made possible and secure because of its strong central structural system — a smart design that ties exterior student spaces to their interior counterparts.

“When the school day begins and class is in session, there are only two doors that are open. That’s the front ‘bus drop’ door and the back ‘passenger car’ door. Once the bell rings, everything locks down with a magnetic lock so that everything with the exception of the academic building’s front entry — which is the formal entry — is secure,” said Durham.

“Those doors won’t look until after school ends but should you pass through them you enter a foyer but can go no further. It’s basically a locked vestibule. So they have a lot of control of who comes and who goes and the first person one would meet should they be allowed to exit out of the foyer is the safety resource officer — a police officer.”

Perhaps its crown jewel is a gymnasium comprised of concrete masonry units (CMU) that doubles as a FEMA-rated storm shelter accommodating three times the school population.

“We’ve done a lot of schools that have done extremely well with concrete block, ” said Durham, who noted that Echelon Masonry was their block supplier for this particular project. “We’re really proud of this one.”

The design centers around a commons, an area that connects academics, fine-arts as well as athletics “while also serving as a pre-function space for public events”, according to the firm.

“The academic wing’s prominent two-story facade was placed west [of the commons], taking advantage of traffic visibility along the campus’s west edge, while wrapping itself around an outdoor courtyard with controlled access.”

“The auditorium, north of the commons, anchors the fine-art wing surrounding it. It hosts public events year-round, thus optimum professionally-designed acoustics were provided. The gymnasium, east of the commons, aligns with the existing high school competition gymnasium, allowing their simultaneous use for tournaments/events.”

Additional features include, collaboration spaces, central locker area, cafeteria seating options, including outdoor dining.

The construction cost for the entire project came in at about $34.6 million, with a building area of 180,000 square feet ($192 per square foot).

But it’s not just the local community, Dorn, and those at Durham’s firm that are pleased with the final, finished product. Recently it was awarded the 2019 Top Block Design Award by the Alabama Concrete Industries Association at this year’s North Alabama Chapter of the American Institute of Architects (AIA) Design Awards — an honor so prestigious that it’s given to just one project per calendar year.

In the Times Daily, Association president John Sorrell called the school “timeless and will still look great in the next 10 or 20 years and not feel dated.”

“We were trying to keep a low maintenance and high durability structure, and obviously block is ideal for that scenario as long as it’s maintained, which this school system does a really good job of doing,” said Durham.

For more information on AIA North Alabama, go their Facebook page.

A Car Ride From the Big Apple, a Sanctuary in the Catskills

It’s late in the afternoon on a Friday. Almost the weekend. Architect Jason Shannon is on speakerphone, in his car, giving details about the very place he’s driving to from New York City: a concrete block home he and his wife designed that rests in Upstate New York in a county once famous the world over for retreating from Manhattan, and comedy.

“It’s our house, my wife and I, so we got to use our own personal desires for it.”

Jason and his wife, designer Paola Yañez, together run  J_spy, in Jersey City, New Jersey — a firm that was recently featured for this project in dezeen.

“When it came down to our main material,” he recalls. “I think masonry we liked a lot because we live in the New York City area and we deal with a lot of old townhouses that are brick.

“They’re a hundred years old but everyone still desires them because they look great.”

With a cut stone look in mind, they went to NCMA member Kingston Block where they were shown a number of options — namely the ground face colors. They went with the darker variation.

“It’s almost like a terrazzo in a way because it’s smooth but you still see the texture of it.”

“[Concrete block] was a good, affordable option to get the look we were going for.”

As an easy retreat from the Big Apple, the location makes a lot of sense. There’s a lot of history backing it up.

Where the home rests, in Upstate New York’s Sullivan County, is the very same county where a string of resorts known as the “Borscht Belt” used to be. For much of the twentieth century their stages served as the springboard for the careers of iconic comedians like Jerry Seinfeld, Joan Rivers, Woody Allen, Andy Kaufman, Rodney Dangerfield and dozens more.

No longer an entertainment epicenter, the region is a quiet, ideal location for a peaceful respite from a city famous for its fast pace, honking horns and cantankerous commotion.

Among a dense forest of pines and a few acres of high grass dotted with blueberry bushes, the home looks out onto the raw nature that cradles it. Its connection to the outdoors and its minimal footprint work in tandem through its deliberate design.

“This house shows our design goals unfiltered. This is the kind of work that we want to do: very minimal. It’s taking everything from building code to tech to the client’s desires and distilling it down to something pure and simple.”

“Masonry makes us think of Europe — it’s one of those materials that lasts really well and it’s something that almost gets better with time. It’s one of those materials that you feel like in another hundred years it’ll still look good there.”

“And we wanted something durable.”

The entire space is single story and is 1,145 square feet. It has two bedrooms and an open-plan living/dining area. Resting atop the masonry walls is a white, metal-clad box that ever-so-slightly cantilevers over the structure. The ceiling features skylights that usher in daylight as well as fresh air.

“The house is environmentally sensitive through the use of an extremely efficient geothermal heat pump connected to a concrete radiant floor used for both heating and cooling. The metal clad volume creates overhangs for passive solar heating while creating 14-foot ceilings on the interior,” said the studio, according to a project description.

Photography is by Amanda Kirkpatrick

A Few Good Materials

Camp Pendleton Marine Corps Base, 41 Area
Owner: Naval Facilities Engineering Command (DOD)
Architects: Vazquez Marshall Architects; TranSystems; and Wildman & Morris
Contractor: Webcor/R.A. Burch
Block Producer: RCP Block & Brick
Photographer: Pam Martin PJ Photography

41 Area, one of the largest mixed-use sectors of the U.S. Marine Corps Base at Camp Pendleton, CA, has just undergone $133 million of renovations and new construction as part of a major expansion of operations and training facilities for the Marine Units stationed there. In a single contract for three diverse campus projects, Webcor/R.A Burch, San Diego, CA, constructed 18 new buildings; all of them concrete masonry structures.

New and updated facilities at Camp Pendleton were needed to accommodate increasing numbers of military personnel and their families assigned to the busy base. A $3.1 billion, multiyear modernization plan for the nation’s main amphibious training site was put into motion by the Naval Facilities Engineering Command (NAVFAC) Southwest in 2010, and much of it came online in 2013. These durable and secure structures are attractive, inviting buildings, often clustered together as small communities with their own town centers.

One of the underlying goals on military bases today is to create an atmosphere that doesn’t look or feel like a typical military installation. Instead, the Department of Defense seeks to create mixed-use developments, complete with residential buildings, office buildings and light industrial applications. Within many of these mixed-use projects are retail areas, community centers, educational facilities and recreational areas.

Under its design-build contract, the joint venture Webcor/R.A. Burch was responsible for a wide variety of building types on three sites: the Bachelors Enlisted Quarters (BEQ) Campus, which included an extensive Fitness Center and Community Center for Single Marines; the 1st Reconnaissance Battalion Headquarters Campus and the 1st Air Naval Gunfire Liaison Company. In all, there was 500,000 sf (46,452 sq m) of new construction put in place in three years, requiring 60 designers from three architecture firms, 25 site managers and more than 200 on-site workers. Retail space, warehouses, offices, housing, medical and emergency services, training facilities and automotive and electrical shops are among the new buildings in 41 Area.

The Marine Corps’ goal was for Camp Pendleton to support the mission and operational effectiveness of varied users with appropriate and efficient facilities, which meant that most of the existing buildings in this 50-acre (20 ha) mini-base within Camp Pendleton were demolished to make way for new structures.

Camp Pendleton exemplifies all the reasons to use concrete masonry in a mixed-use development: it is attractive, strong, durable, and provides many of the health, safety, and welfare benefits sought by the Department of Defense in its built environments. Those are very similar to the benefits any private developer or local government would set for a large project or a new town center. In 2010, about the time contracts for the new buildings were being awarded, the Marine Corps issued its ‘Base Exterior Architecture Plan’ (BEAP) for Camp Pendleton.

CMU is the only choice

BEAP is a directive targeted to developing a functional and visually cohesive environment at Pendleton. It provides a design link between old and new facilities. Guidelines establish very specific design criteria for everything from site planning, to streets, to landscaping, and most notably to building structures and façade walls, all of which must be concrete masonry. The idea is to promote design unity at Camp Pendleton, which in turn will strengthen Pendleton’s public image, improve recruitment and retain personnel.

According to the BEAP, concrete masonry architecture is mindful of its immediate surroundings, is functional, has a consistent visual image in terms of form, material and color, is timeless and flexible, and has life-cycle-cost benefits. Led by the Architect of Record TranSystems, the design team included Vasquez Marshall Architects, and Wildman & Morris, who all worked closely together to create the visual cohesiveness for the area that the Marines were looking to achieve.
There was never a discussion of the exterior structural material system, according to Rob Bodenhamer, Project Architect with Vasquez Marshall Architects for the BEQ/Community Buildings project. NAVFAC was looking for buildings that would endure and quickly determined that CMU envelopes would provide the consistent aesthetics, energy conservation, security, low maintenance, fire safety, and long life it needed for all of the building types on the campus. Before contracts were sent, the owner reaffirmed that its criteria would be uniformly addressed only by concrete masonry. “Everything at Camp Pendleton needed to comply with the design standard. The BEAP dictates the size, shape and color of the masonry because it needs to work with what they’ve been building there at the Base for the last 20 years,” Bodenhamer said.

The newest BEQ site is intended to set a new, higher standard in the 41 Area. Located here are a 200-bed BEQ—one of 39 new dormitories—community center, fitness center, recreation center, retail outlet/exchange and a 2-story parking structure. The multiple buildings form a campus-like atmosphere with a clear sense of arrival and order through circulation and access to amenities. Design and construction followed sustainability criteria, and most of the buildings have received a minimum U.S. Green Building Council LEED-NC version 2.2 Gold rating. A few have Platinum designation.

Analysis of the BEQ site, its prevailing winds and its solar orientation, along with vehicular and pedestrian circulation, led to an L-shaped campus for this section of 41 Area, according to Bodenhamer. That shape helps create the sense of a smaller community within a larger town. The all-CMU construction BEQ buildings are connected by a series of walkways with resort-style activity courtyards, basketball courts, horseshoe pits, and volleyball, along with an outdoor amphitheater at the east end of the promenade. There are also picnic shelters, and covered barbeque areas constructed of CMU columns with standing metal seam roofs to minimize maintenance, says Bodehamer.

“As part of the design concept and meeting or exceeding the increased ‘quality of life’ goal, we wanted the Marines to have a place to spend their free time and really enjoy being a local community. The design concept can translate directly tosimilar public or educational projects where you create a sense of community with supporting amenities and opportunities for people to interact and socialize,” he said.

An exemplary BEQ complex

The BEQ’s buildings’ massing and grouping of units are based on a typical masonry module. The design rhythm relies most often on groupings of eight CMU constructed in either textured or smooth block and various colors. The eight-unit groupings help to delineate specific features such as breezeway openings. The masonry group economically creates visual interest as a strictly functional feature— in this case an opening intended to provide natural ventilation, says Bodenhamer.

Exterior finishes and colors adhere to the BEAP standards, and by incorporating sustainable design concepts, Bodenhamer says they were able to reduce maintenance requirements and lower overall energy demands, which contributed to the LEED designations for the whole campus

The BEQ elevations are articulated both vertically and horizontally to provide smaller footprints that are more residential in scale. The Marines were very particular about the block colors used at Camp Pendleton and issued a list of specific block colors and their manufacturers, although a provision was made to allow “or similar” colors by unlisted manufacturers.

Rather than an integral admixture for moisture resistance, all the block in the 41 Area BEQ Campus had surface sealant applied. “We specified an applied penetrating sealer for the exposed integral color masonry which provided a durable, low maintenance finish and eliminates the costly and disruptive maintenance of a painted surface,” said Bodenhamer. That is one of the very few maintenance items required on these masonry buildings. “For the best performance, the sealer will need to be reapplied in five to 10 years,” he said. He adds that Camp Pendleton is in a very dry area. He would normally specify a moisture-resisting admixture for military, public or private masonry building projects. But the climate allowed NAVFAC to rely on a periodically re-applied sealer. The BEAP calls for material selections for new buildings to be based on the materials’ durability and low-maintenance qualities, and for painted surfaces to be typically avoided.

A restriction to using only concrete block, in only a few colors on the mixed-use complex was not limiting, says Bodenhamer. “It is a regular size, modular building component that actually provides lots of flexibility when the variety of finishes, textures and colors are considered.” Nearly three-quarters of the exterior CMU Vasquez Marshall specified is architectural block, with an enhanced finish, arranged in textures and patterns to break up the building mass and to highlight some of the building elements. Darker, split-face block is used on the lower portion of the buildings to establish a visual base and maintain a clean appearance. Meanwhile, the architects used highlighted horizontal accent bands of CMU to tie the building elements together and define openings around windows and doors.

The Community Center is the main feature of the BEQ campus. “We’ve provided a clear and readily identifiable front door by way of a ‘hotel-like’ entry pavilion,” said Bodenhamer. “Concrete masonry creates an easily recognized covered entry pavilion, guiding the occupants from parking areas and surrounding facilities by way of a paved walkway and landscaped promenade, to the main entrance of the Community Building.”

In addition, a covered walkway with concrete block columns and a standing seam metal roof links the Community Building to the breezeways that lead to the living units. The covered walkway links directly to the main elevator and its stair tower. That CMU elevator tower is centrally located in the BEQ campus and serves as the focal point.

Walls in circulation areas and in interior spaces where people are likely to come in contact with the surfaces are smooth block. In these areas, color is the main ornament, and rougher textured block is less likely to be specified, according to Bodenhamer. Smooth block with small radius corners is also used at doors and entryways.

Safe and secure

While the BEAP turns much attention to using concrete masonry to establish visual cohesiveness at Camp Pendleton, NAVFAC finds CMU offers other advantages as well. Block’s contribution to safety is one. The inherent fire-resistance of concrete masonry means it doesn’t burn and it retains its structural integrity. It can prevent damage when reinforced and avoid progressive collapse during a fire or other disaster.

These are masonry buildings with fire-safe construction on the envelopes. Interior walls required a minimum 30-minute separation between living units and breezeways in most areas. Masonry wall assemblies can exceed that rating.

The overall site was designed in strict reliance on the BEAP’s guidelines, which address many of the concerns about wildfires and acknowledge the Fireland Management Plan for that area of California.

The location and orientation of the 41 Area BEQ Campus buildings were specified to comply with Anti-Terrorism/Force Protection standards. While at the time of design the standards called for an across-the-board standoff, or setback, distance of 82 feet (25m) from roadways, parking areas and trash enclosures, the masonry buildings offer much greater protection.

Under that same standard fully grouted, reinforced CMU allowed the standoff distance to be reduced to 35 feet (10.7 m) from these potential threats. In addition, the grouted and reinforced walls offer greater seismic load resistance, protect against progressive collapse and provide greater fire resistance than competing wall systems. The Marine Base at Camp Pendleton is vast, so the question arises as to why just concrete masonry structures alone were specified by the BEAP. The BEAP answers that directly. It says that the architectural design should be simple, straightforward, flexible and reusable, and use compatible, durable, cost-effective materials like concrete block and glazed concrete block to achieve the primary mission of the facility for a singular, unifying architectural vocabulary. The Marines have learned that using just a few dependable materials in such a big way will pay dividends for many years.

Atwater Crossing Residences are CMU, Not Wood

The design intent for the 27 residences at Atwater Crossing in Los Angeles was to create homes with open floor plans that were filled with natural daylight and would also meet the highest level of environmental standards. That goal was the starting point for a number of unique decisions that would ultimately result in LEED Platinum certification for these homes.

CMUs met all the design criteria for the residences

A combination of materials was selected to express the design, including concrete masonry, not a typical material solution for low-rise, townhouse or single-family home construction in Los Angeles. But, according to architect Charles Kluger, AIA, of Kluger Architects, Signal Hill, CA, along with using recycled building materials whenever possible, the design team included many features that make the project friendly to the environment. One surprising decision was to avoid the use of wood.

Wood accounts for less than 1 percent of building materials in the homes at Atwater Crossing. Using concrete masonry units readily contributed more material points for Platinum LEED certification because it was a long-lasting sustainable material, according to the designers. The exposed concrete masonry materials contributed about two LEED points to the project. To earn a Platinum LEED designation, the building construction is expected to surpass California Title 24 Energy Code Standards by 15 percent or more. The energy-conserving envelopes of the homes were reported to be more than 30 percent better than Title 24 requirements, with the concrete masonry shouldering the additional energy loads imposed by the front and back glass walls.

Recyclable, renewable and abundant

Instead of wood, the homes are constructed of materials the designers deemed “recyclable, renewable, and abundant.” The homes are constructed primarily of steel and concrete masonry, along with aluminum and glass. The hybrid structure combines CMU shear walls on the sides of the homes and a steel moment frame, according to Kluger, to account for potential seismic loads. The intent was to highlight, not hide, construction materials, so very minimal wall finishes were employed. The minimal finishes used were selected to harmonize with the simple nature of the design. Even the garage doors almost seamlessly integrate into the glass curtain walls. The designers chose the rustic look of split-face block for exterior walls, and inside the smoother side of the block is left exposed for half of the wall surfaces.

The first floor includes a two-car garage with a dumbwaiter to the kitchen above and also to a usable roof deck. There is a flexible space intended as an office or extra bedroom, and a fully retractable glass wall at ground level. The second floor contains open plan public spaces, and the living room space has more retractable glass walls. Elevated ceilings in the private living spaces on the third floor contribute to the strategy of featuring the masonry materials as a design focal point, again with judicious use of other finishes. A walkable roof comprises the fourth floor, with its concrete masonry walls, outdoor kitchen, private bath, garden and lounging area.

Concrete block, steel beams, and even mechanical systems were left exposed by design. The full-height masonry walls offer many aesthetic and maintenance advantages in the individual units, and serve to visually anchor the front and back curtain wall ends of the homes at the street. The homes have been virtually maintenance free.

The materials selected for the residences at Atwater Crossing provided the design solution of vertically integrated open volumes with cantilevered floors. The open plan means that daylight can reach into all spaces.

“The idea of natural light filling every space was significant,” according to Kluger. The glass curtain wall systems open front and back walls of the envelope to natural light. The architects specified glass doors for interior rooms, so spaces that are typically illuminated by artificial light in most housing developments are instead filled with natural light at Atwater Crossing.

Kluger points out that all the materials used, but in particular, concrete masonry,“are very low maintenance and highly durable, which means that future resources will not be required for upkeep and repairs. The block is natural and enduring, reinforcing the idea that these are timeless buildings.”

A Shining Center Upon a Hill: How SRWs Turned Elevation Into an Asset

Sometimes a grassy hill is all you need to transform a community.

If you venture to 550 Shrewsbury Commons Ave, Shrewsbury, PA, right now, you’ll see a modern shopping center on an impressive expanse of land along with other buildings, roads and parking lots. But it wasn’t always that way.

Not long ago there was just a hill there. Which, to most builders, poses a real challenge: it was large and it didn’t possess any flat areas to build on.

However, with the utility and power of segmental retaining walls, this obstacle soon became a striking feature — rather than a problem.

The owner and developer built and used segmental retaining walls throughout the property to hold up the necessary roads, parking lots, building and signs before turning it into a commercial center. Today, the shopping hub exists and thrives because it is anchored by this particular product: segmental retaining wall units, or SRWs.

For this project, Cornerstone 100 retaining wall units were used, produced by York Building Products. Strata geosynthetic soil reinforcement was used as well.

The largest segmental retaining wall used ascends to an exposed height of 39 ft (12 m), making this project truly grand and impressive.

For information on CornerStone 100 retaining wall blocks, click here. For more information York Building Products, click here. For more information on Strata, click here.

Keeping Cool With CMU

Armory Park, Tucson, AZ
Architect: Lizard Rock Designs, Tucson, AZ
General Contractor: W.E. O’Neil. Phoenix, AZ
Masonry Contractor: Hobbs Masonry, Phoenix, AZ
Block Producer: Superlite Block

Armory Park is a residential project devoted to elderly housing in Tucson, AZ. At six stories high, it is also one of the tallest post-tensioned buildings in the nation. Relying on a proprietary CMU configuration, the blocks create a loadbearing masonry wall system with superior thermal performance properties.

With 143 one and two-bedroom units in 139,000 sf (12913.5 m2), this low-income project was an important one for the owner Senior Housing Group, which was looking to develop a sustainable building. Lizard Rock Designs Architect, Tom McQuillen, designed this building to Leadership in Energy and Environmental Design (LEED) Gold standards. He was able to achieve that designation on a very tight budget, thanks in large part to the post-tensioned CMU construction.

Sustainable and Cool

“Initially we designed the building with insulated concrete form (ICF) wall construction,” McQuillen said, “because we thought it was a good way to get the energy savings we wanted and it would be cost effective.” But the general contractor W.E. O’Neil convinced him otherwise. “The contractor said the system was fine for lower buildings, but they had experience with ICF on buildings six stories and higher, and hadn’t been pleased with the results; it was too hard to get the forms straight all the way up.” And the extra work required on the forms would drive the cost up.

McQuillen found the proprietary block to be a great product and is pleased that the CMU can be hydraulically post tensioned and then the cells filled with foam, enhancing the energy conservation and contributing positively to LEED points. “This wall system was the main reason we came in 28 percent better on utility use than the most stringent energy codes,” he said. “ And we even got points because the block was locally-sourced.”

Safe and Quiet Gives a Lot of Peace

The building is all block construction, and interior partitions are set at 28 ft (8.5 m) modules and are built with standard CMU. The driving force for the block interior walls was fire code compliance, but there was an unanticipated bonus. “Combined with precast floors, the masonry interior walls prevent most of the sound transmission,” reports McQuillen “This is a really quiet building.”

Truman Learning Center – Shelter From the Storm

Farmington, MO, School District
Architect: Hoener Associates
General Contractor: Brockmiller Construction
Mason Contractor: Foeste Masonry, Inc.
Civil and Structural Engineer: Toth & Associates, Inc.
Producer:  Midwest Block and Brick

Recognized for its ability to weather the march of time, masonry construction also withstands times of bad weather. The Truman Learning Center in Farmington, MO, could change its name to “Truman Learning Shelter” based on the dual purpose designed into the early childhood development center’s new wing addition. The Farmington School District selected loadbearing masonry construction with a brick veneer for the addition of two new wings to the school. One of these wings bears the distinction of functioning as a Federal Emergency Management Agency (FEMA) rated emergency shelter, as well as a developmental learning center.

“We never want to use the center as a FEMA structure. However, if we do have winds up to 250 mph, this is where I would want to be,” said Kim Johnson, principal, Truman Learning Center. “One of the most important factors when we were making plans for the new building was to be able to tie in to our existing structure.”

Bringing the 1930s into the present

The original buildings that now comprise part of the Truman Learning Center were built in the 1930s such as the Farmington High School auditorium. The original brick set the tone for the new full masonry construction addition, while at the same time nodding to contemporary options and styles. “Working in a traditional or classical masonry style, we borrowed the keystone elements above the windows and the corbelling of brick from the original building in our new construction,” said Wade Welch, project architect of Hoener Associates Architects. “Matching the brick color to the original was our primary interest.” In addition to providing early childhood education for 400 youngsters, the Truman Learning Center expansion was also designed to function as an emergency shelter during severe weather and intense wind.

Loadbearing concrete masonry provides structural strength

A loadbearing masonry structure provides the level of safety necessary to meet FEMA’s standards for a storm shelter, while daily creating a warm, nurturing environment for children. Twelve-inch wide concrete masonry units (CMU), fully grouted and reinforced with two #6 rebar per cell, provide a structural support rated to withstand winds up to 250 mph and the impact of an eight-foot 2×4 shot at 100 mph. Welch notes that construction projects of this nature often favor masonry for both structural and aesthetic solutions. “It seems the cost of precast construction rises when you get further away from larger municipalities,” said Welch. “Contractors in these areas are more familiar with masonry construction, which gives more flexibility in design than precast concrete.”

The architect sought to break up the visual mass created by 74,000 bricks plus in the veneer and add character and warmth to the structure by using split-face CMU treatments at the base of the walls and piers. Cast stone lintels with keystones, corbelled brick and piers define every classroom window. Cast stone accent panels bearing the school’s logo – a knight – are strategically placed on the walls in high traffic areas, such as the main entrance and playground. “We wanted to include a punch in certain locations to accent the design,” said Welch. The majority of the school’s eye-pleasing interior was accomplished by utilizing durable painted CMU. The exterior red brick transitions into the building’s main entrance vestibule and lobby, setting the tone for a welcome visit. Meanwhile, brick piers help define the main office area.

Meeting the needs of safety and learning

Foeste Masonry, Inc., rose to satisfy all the project’s needs from building a solid, reliable and durable structure that will shelter a community from a storm to creating a pleasant and welcoming space where children will learn and grow. Foeste Masonry has built a number of FEMA shelters.

“It was the first time I worked with Foeste Masonry, Inc., on one of our projects,” said Welch. “I was impressed with their attention to detail on both reinforcing the FEMA portion, as well as the veneer portion when we were doing such a critical tie-in to the 1930’s era building.”

Article and photos courtesy of  the Masonry Institute of St. Louis.

Revitalization of a Runoff Canal With ACBs

With neighborhoods being threatened with flooding and erosion, Florida Department of Transportation (FDOT) used articulating concrete blocks to redirect stormwater runoff.

Even in sunny Orlando, FL, the rain comes, and when it does, flooding is a primary concern. Runoff from roads and highways flows rapidly through ditches such as State Road 434 Out Road Canal, installed years ago by FDOT. Florida has been regulating stormwater discharge and management since the 1980s with the intention of protecting its surface waters.

The Florida Department of Environmental Protection (FDEP), regional water management districts and local governments all have oversight responsibilities for stormwater runoff. FDEP requires 80 to 95 percent reduction in the annual loads of pollutants from rainwater discharge. Meanwhile, the City of Orlando maintains its streets to keep them clean, safe and in good repair. Orlando also ensures that the drainage facilities perform as intended and that receiving water bodies meet state and federal water quality standards.

The aging drainage ditch that served a portion of State Road 434 had been eroding over time, according to Dale Mudrak, project engineer with Gregori Construction and Engineering.

Local properties in the residential neighborhoods where the water runs through were threatened with erosion and potential flooding. In order to prevent further damage, FDOT applied to the regional water district for a permit to make improvements on the 434 Canal drainage ditch, which serves as a conveyance system to channel runoff brought in from the State Road, two adjacent subdivisions and a lake at its head. That runoff ultimately flows into Little Wekiva River and through Wekiva River Buffer Conservation Area, with its fragile wetlands that are often flooded in the rainy season. The local water district officials recognized the need for improvements to the outdated infrastructure. However, the contractor was required to include vegetation along the canal bank and maintain the plants for one year to mitigate the loss of natural vegetation during construction.

Like much of Florida, the canal banks were mostly sand, so any rapid flow in the drainage canal would lead to erosion. Flowing stormwater added to the canal from the adjacent residential properties caused the erosion to increase, especially in areas with no vegetation or where the area lacks stabilization.

ACBs meet site challenges

Ready mixed concrete was first considered for the project, but there were site restrictions that could not be met with that solution. Access to the drainage ditch near the two subdivisions was restricted; too small to get a ready mixed truck on-site. In addition, the FDOT was seeking a sustainable solution allowing plants to grow in the revetment area. “So they went with articulating concrete block (ACBs) instead of ready mix,” Mudrak said.

The proprietary ACBs selected for this 25,000 sf (2322 sq m) project were 6 in units (152 mm). They were installed as mats, which required a crane for placement. Mudrak says the contractor got permission from two homeowners to bring in a crane between their properties, and the clearance was so tight that the crane’s retractable wheels had to be withdrawn.

Steel sheet piles were used across the canal to slow down the speed of the runoff. When the velocity of the stormwater is decreased, particles in it have time to settle out on the bottom, helping to clear the water. “The ACBs are extremely important in periods of high flow after a storm event as water will flow around or over the sheeting weirs, actually increasing water speed,” says Mudrak. When that happens, the ACBs will keep the bottoms and sides of the canal from eroding away.

The Florida Administrative Code’s Water Resource Implementation Rule sets design criteria for stormwater systems. In situations like State Road 434, where the runoff discharges into the conservation area of Wekiva River, the rules require a 95 percent reduction in pollutant loads. Water quality was a big issue for the drainage project and one of the critical factors for why FDOT chose ACBs, according to Mudrak.

Technically ACBs were considered a conveyance system, not a treatment system on the canal but actually accomplish some of both. The combination of the steel weirs and extensive ACB mats offer some water treatment benefits. By slowing down the water flow with the steel sheeting, there is less erosion and some of the sediment carried in the runoff has time to settle to the bottom.

As for treatment, the ACBs allow vegetation to grow in the open cells along the canal’s banks. The vegetation then absorbs nutrients from the water which cleans it. The open cells on the bottom of the canal allow sand to settle and keep it from continuing down stream. Once established, the natural vegetation can hide the ACBs that are stabilizing the slopes. The life expectancy of this drainage conveyance system, with its treatment qualities, is 50 years.

“We see ACBs as one of the solutions to erosion and slope stabilization issues. They are an engineered product and in many cases provide better performance than natural products. We expect to see continued lower overall cost utilizing ACBs compared to other products which is due to limited amounts of natural resources and the increased cost of trucking them. The quality of the ACBs combined with design flexibility and production sizes—both thickness and mat size—make it preferred by owners, designers and contractors,” says project engineer Mudrak.

Florida Manages Orange Avenue Bridge With GRS-IBS

An old, deteriorating trestle bridge above an historic trail in Tallahassee, FL, was scheduled for replacement. Orange Avenue Bridge sits above the intersecting bike and pedestrian trail portions of St. Marks Trail. Replacing the 60 ft (18.3 m) bridge would be straightforward in most circumstances. But this short-span bridge construction project faced a number of challenges.

With a bike path and a pedestrian trail directly below the bridge, there was little room to excavate support walls. And timing was critical, as the road serves an elementary school and is in frequent use most of the year. In addition, the Florida Department of Transportation (FDOT) had a limited budget for the replacement project.

Once school was out and summer recess underway, the road was closed so construction could begin. The old bridge was removed and excavation for the new support walls began. A proprietary concrete block retaining wall system was specified for its near vertical batter, which helped alleviate the space restriction issue and also allowed for a much wider passageway for the trail below the bridge.

Speeding up construction time through completion was a high priority for this project. The concrete block face walls are dry stacked, and as a result, the abutment walls were rapidly erected and ready to support the superstructure. With dry-stacking there was no cure time required, meaning that the abutment wall construction was not interrupted at various courses and so installation progressed ahead of schedule. The abutment walls were 18 ftt high (5.5 m), with acute angles that necessitated special cuts in the block, along with rebar reinforcements at the corners and on the sides. To prevent the corners from separating, block cores were filled with grout, from top to bottom. The Orange Avenue Bridge opened to traffic 23 days ahead of schedule.