Air, Vapor and Water Resistive Barriers Project

Reading Hospital Seventh Avenue Building – Reading, PA

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At 476,000 square feet, the $354M Seventh Avenue Building, designed by Philadelphia architecture firm Ballinger and constructed by LF Driscoll Co. of Bala Cynwyd, PA, will increase the floor area of Reading Hospital’s West Reading, PA facility by 20 percent. The state-of-the-art expansion, currently the largest healthcare construction project in Pennsylvania includes five floors of private patient rooms, technologically-advanced operating rooms, and consolidated trauma and emergency departments.  Despite its considerable size, the addition will be architecturally sensitive to the existing campus, and incorporate numerous sustainable design features, including a two-acre green roof, natural daylighting and views, and a continuous air barrier system designed to conserve energy.

Concealed behind the brick, limestone and granite cladding is a continuous air barrier membrane covering the opaque exterior wall sheathing and 17,000 lineal feet of Pecora XL-Span Pre-formed Silicone Transition Membrane connecting the air barrier to the aluminum-framed window and curtain wall units. XL-Span is an extruded, 100% translucent silicone membrane that forms and air- and water-tight barrier at wide gaps between building façade components.  Glazing subcontractor R.A. Kennedy & Sons of Aston, PA also used 1,500 sausages of Pecora’s AVB Silicone Sealant to adhere XL-Span to wall and window surfaces as well as 500 gallons of Pecora’s 890NST Nonstaining, Ultra-Low Modulus Silicone Sealant to seal window and curtain wall perimeters, panel joints, and stick-built curtain wall joints.  Together with the opaque air barrier membrane and sealed windows, Pecora’s XL-Transition System (XL-Span and AVB Silicone Sealant) will form the building’s defense against air leakage thereby contributing to greater energy efficiency, structural durability and longevity.

Prior to fenestration installation two exterior wall mock ups were constructed and tested by Intertek/ATI and witnessed by Ballinger and building envelope consultant, Wiss Janney Elstner Associates. During the shop drawing submittal period, at the request of R.A. Kennedy & Sons, Pecora Technical Services conducted a comprehensive review of the mock up drawings to confirm proper application of Pecora products.  In addition, preconstruction laboratory adhesion testing was successfully completed by Pecora to ensure the best results.  With all components in place, the mock ups were subjected to a battery of tests including static air infiltration, water penetration, uniform structural loading, differential movement, thermal cycling, and seismic movement.  Upon completion, all Pecora products performed satisfactorily without de-bonding, tearing, rupturing, or permitting air and water infiltration beyond specified limits.

Witmer Waterproofing of Mount Joy, PA weatherproofed the 9-story building’s exterior cladding by installing 500 gallons of Pecora’s 890FTS Field Tintable, Nonstaining Silicone Sealant in exposed stone and masonry control and expansion joints.  Available in 51 standard colors, 890FTS, permitted close color matching to the building’s red brick, granite and limestone cladding and trim without incurring additional cost for custom color matching.  Due to its convenient Universal Color Packs and smooth or textured finishes, 890FTS offers maximum jobsite flexibility.  Pecora Distributor, TB Philly performed successful field adhesion testing at the site.

They say, “The devil is in the details,” and this project is no exception. Due to Pecora’s long-standing relationship with Ballinger, our sealants were a natural fit for the project’s specifications.  Pecora’s XL-Transition System, together with 890NST nonstaining silicone sealant and 890FTS field tintable, nonstaining silicone sealant keep the outside air out and the inside air in; prevent air movement through gaps between the windows and surrounding wall; and enhance the building’s aesthetics.  Unchecked air movement carries moisture, odors, spores, pollen, and can be hot or cold relative to the indoor air temperature.  Air barrier accessories like XL-Span that are impermeable to air and water-resistant contribute to increased energy efficiency, greater structural durability and improved indoor environmental quality.  In turn, these contribute to successful patient outcomes and a better financial bottom line.

Rendering courtesy of Ballinger.

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