HealthSource finds Structural & Thermal Efficiency with Single Wythe Brick

Graham Kalbli

The owner and design team agreed the over all design intent for the two new HealthSource primary care facilities in suburban Cincinnati was to convey a sense of permanence and institutional quality, yet also convey a warmth and welcoming sensibility as these buildings were designed to fit into an existing community fabric. A brick exterior was easily decided upon as the material best suited to achieve that intent.

Simply Advantageous

Early on, strategic decisions for the overall super structure were made. It was decided the buildings should be constructed as simply as possible. We chose structural brick instead of mixing systems, such as steel frame structure and a brick veneer. Several factors influenced the decision to use single wythe masonry as a load bearing structure and exterior finish wall, including

• Uninterrupted continuous insulation on the inside of the building envelope in order to take maximum advantage of the super-insulating qualities of an unbroken thermal envelope

• Reduced lead time and costs associated with steel-framed building assemblies

• Clear span roof structure resulting in no interior bearing walls on the inside of either facility

• Rapid construct-ability during a short construction schedule

By using an 8″ bed depth structural masonry unit, all steel columns were able to be removed, as were structural steel bumpouts along the perimeter walls for more usable interior space. Roof trusses and roof framing were allowed to bear directly on the exterior masonry wall. This greatly simplified the structural system and reduced lead time and costs associated with steel-framed building assemblies.

Due to deadlines that needed to be met to secure funding, the team did not want to lengthen the construction schedule by developing a multi-material wall system. Single wythe masonry allowed both exterior veneer color selections and structural capacity to be handled with one material selection. This resulted in maximum construct-ability during a short construction schedule. Walls were up in just a few weeks. An 8″ w x 4″ h x 16″ l unit was chosen for its installation efficiency and high compressive strength.

The Eastgate and New Richmond facilities were designed at the same time and are proto-similar. Their material selections and configurations are basically the same. Each consists of a central service hub with nurses’ stations, labs, medicine repositories and other common spaces. On either side of this central core are two circulation spines lined with clerestory windows. These spines separate the core from the doctors’ pods, which essentially wrap the exterior of the building to take advantage of natural lighting and views with a window in each pod. Each doctor’s pod has one doctor and three exam rooms arranged in a linear fashion down the long access of the circulation corridors. In the New Richmond location, the building is a one-story slab on grade. The Eastgate location includes a basement on the lower level, intended to be used as a pharmacy, offices for business operations and a dental clinic.

The overall exterior skin of the building consist ed of three different brick colors – tumbleweed, nutmeg and brandywine. The masonry was laid in a running bond pattern with a stacked soldier course of the brandywine brick at the top of the building just under the coping. Tumble weed was used alternately with nutmeg as the field color and to offset entrances.

Green Buildings

Both projects earned LEED Certified ratings under LEED 2009. Clay masonry helped the project qualify for credit 5 Regional Materials of the Materials & Resources (MR) category as all the clay and shale was extracted 10 miles from where the brick was manufactured. Manufacture took place less than 200 miles away from the project site—well within the LEEDrequired 500 mile radius. The three different color units each contain at least 25% preconsumer recycled content, contributing to points earned for MR credit 4 Recycled Content. Brick, brick packaging materials, mortar and grout are recycl able and contributed to the point earned for MR credit 2 Construction Waste.

Additionally, as previously mentioned, the single wythe masonry (R1.1) is a critical component in the super cooler, or igloo effect, that the building envelope creates for the mechanical systems to run extremely efficiently, thus gaining credit 7.1 Thermal Comfort points in the LEED Indoor Environ mental Air Quality category. The fenestration is approximately 35% of the exterior vertical envelope, within the 2009 IECC guidelines for energy efficiency (40% maxi mum). The mass portion of the wall is fully insulated with a closed-cell polyure thane spray foam continuous insulation (R6.75/”). This insulation is sprayed on the interior of the masonry, between the studs and covered by gypsum board wall finish. Insulation limits heat flow, but also works to minimize air leakage (convection) and acts as a vapor diffusion retarder. The opaque wall system has an R-value of 30. The facilities are designed to achieve 40% energy savings over base line. This system also contributed to the points earned in the LEED Energy & Atmosphere category, credit 1 Optimize Energy Performance.

Compounding Benefits

The masonry wall with spray foam insulation offers additional benefits to the owner that will continue to serve them well as they serve their patients. Brick is durable and a low maintenance material. Neither it nor the insulation chosen provides a food source for mold or pests. The brick has a sound trans mission rating of 52, high enough to minimize traffic noise, which is significantly improved with the addition of insulation, thereby creating a more comfortable indoor environment.

HealthSource, a private, not-for-profit Federally Qualified Community Health Center (FQHC) which offers primary care services throughout southwest Ohio, is monitoring building operations and performance, as they intend to continue to expand the communities they serve. Long-lasting and efficient masonry buildings should provide the necessary facilities to do so.

Graham Kalbli, AIA, AICP, LEED AP, is a project manager at CR Architecture + Design in Cincinnati OH. With a background in urban planning and architecture, Kalbli is an asset to any project team. His focus includes mixed-use developments, urban infill, master planning and adaptive reuse. His inclusive attitude stresses aesthetic appropriateness and urban and natural site responsiveness. Kalbli has been able to develop projects, which prove to be mutually beneficial to both our clients and the communities by first listening and solving problems to create functional, budget sensitive solutions. After earning his Certificate fo Historic Preservation and Bachelor of Urban Planning from University of Cincinnati, Kalbli earned his Master of Architecture from Miami University. g.kalbli@cr-architects.com | 513.721.8080

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