flexiblefullpage
billboard
interstitial1
catfish1
Currently Reading

Building a Double Wall

Building a Double Wall


By By Charles Young | October 12, 2011
The new outer envelope of the A.J. Celebrezze Federal Building serves as a therm
The new outer envelope of the A.J. Celebrezze Federal Building serves as a thermal blanket in winter, reducing the need for mech
This article first appeared in the October 2011 issue of BD+C.

The A.J. Celebrezze Federal Building, a 32-story office building in Cleveland, Ohio, was built in the late 1960s for the U.S. General Services Administration. As with many early generation window walls, significant deterioration has occurred over time due to moisture damage from failed drainage systems. This resulted in delamination of exterior wall panels, compromising the air and moisture barrier. The panels had been stabilized with a retrofit, but their effectiveness as a perimeter barrier has reached its limit, as evidenced by the occurrence of frost inside the exterior envelope during winter.

Our firm, Interactive Design, was engaged as the architect to correct the façade deficiencies for the $121 million project, which is funded under the American Recovery and Reinvestment Act of 2009. To mitigate these issues the façade renovation program was focused on four primary requirements: 1) repair/replacement of the building envelope, 2) providing blast protection, 3) upgrading the energy conservation of the envelope, and 4) maintaining full occupancy during construction.

Blast pressure analysis indicated that the frame of the building would accommodate increased loads, but only at the column floor beam connections. Noncomposite slab construction eliminated the transfer of loads via diaphragm. Therefore, new tube beams were added externally to transfer the wind, blast, and gravity loads to these points. Deflection of the tubes under blast conditions may not impact the structural frame. The geometry formulated an exterior configuration two feet, six inches deep, which led logically to the investigation of a double wall assembly.

Originally the project was conceived as an overclad wall system. However, adding an overclad assembly would have extended the volume of interior spaces, resulting in significant fire protection modifications and perimeter air distribution modifications to the existing fan coil units.

MAKING DOUBLE WALL VIABLE
Double wall technology is one of the most complex building envelope forms. Originally developed and employed in Europe, it has been relatively slow in migrating to the U.S. However, higher energy costs are now making these systems more viable. In new construction, the inability to offset the initial high envelope costs through energy savings historically has been the obstacle for double wall usage. Specialized projects, such as museum construction, can justify these initial costs due to constant temperature/humidity requirements. For renovation projects such as the A.J. Celebrezze Federal Building, the existing interior wall can be reused as the interior skin to offset much of the cost delta.

The design process for double walls relies on the integration of all systems. The ventilation environment of the building informs the design. It is imperative that an accurate and robust energy model be developed to assist in the analysis and creation of the double wall. A fundamental challenge was to understand the effect of a double wall upon the existing building. The design team embarked upon an extensive series of computational fluid dynamic studies. Winter, spring/fall, and summer conditions were run in extreme temperature and solar conditions. The purpose of the CFD analysis was to fully understand the temperature relationships in the wall cavity and occupied spaces during seasonal variances.

The architects were able to manipulate glazing layups, light shades, and frit variations to impact the performance characteristics. The design team pursued a variety of critical design paths simultaneously. These included both actively ventilated and sealed cavity conditions.

A significant factor for this project is that the building has historically a very low winter relative humidity. This ultimately permitted a sealed cavity system with no ventilation from either the inside or outside. The temperature and humidity of the internal cavity are allowed to float, so to speak, with its surrounding environments. It acts as a buffer between inside and outside, mitigating the differences between the two without using additional mechanical means, and minimizing energy consumption.

CUTTING ENERGY USE 65%
This system is designed to improve the existing perimeter energy consumption by approximately 65%. It is most efficient to the building during the winter months, when it acts like a thermal blanket and significantly reduces the need for heat from the existing perimeter fan coils. During summer months, shading systems block direct solar gain to the tenant-occupied spaces. The cavity will increase in temperature while not detrimentally affecting the interior environment or the existing mechanical system.

The final configuration is a noncombustible, sealed assembly that requires minimal maintenance. Access to the cavity is provided at each floor by operable interior windows in the inner wall.

The passive double wall system being employed at the A.J. Celebrezze Federal Building is one solution to the growing number of fully occupied buildings that have aging or seriously deteriorated skins. Economic constraints dictate that building owners cannot afford to empty their buildings of tenants to do replacement or maintenance work on façades. Therefore, systems such as this may offer an alternative to complete façade replacement, at the same time lowering energy consumption and enhancing sustainability by preserving existing materials. BD+C
--
Charles Young is a partner with Interactive Design, Inc., an architecture firm based in Chicago. This article is adapted from Chicago Architect, the journal of AIA Chicago.

Related Stories

Giants 400 | Aug 22, 2022

Top 150 University Architecture + AE Firms for 2022

Gensler, CannonDesign, SmithGroup, and Perkins and Will top the ranking of the nation's largest university sector architecture and architecture/engineering (AE) firms, as reported in Building Design+Construction's 2022 Giants 400 Report.

| Aug 22, 2022

Gainesville, Fla., lawmakers moved to end single-family zoning

The Gainesville City Commission recently voted to advance zoning changes that would allow duplexes, triplexes, and quadplexes to be built on land currently zoned for single-family homes.

| Aug 22, 2022

For Gen Z, “enhanced communication” won’t cut it

As the fastest-growing generation, Generation Z, loosely defined as those born between the mid-1990s and early 2000s, has become a hot topic in conversations surrounding workplace design.

| Aug 22, 2022

Less bad is no longer good enough

As we enter the next phase of our fight against climate change, I am cautiously optimistic about our sustainable future and the design industry’s ability to affect what the American Institute of Architects (AIA) calls the biggest challenge of our generation.

Giants 400 | Aug 21, 2022

Top 110 Architecture/Engineering Firms for 2022

Stantec, HDR, HOK, and Skidmore, Owings & Merrill top the rankings of the nation's largest architecture engineering (AE) firms for nonresidential and multifamily buildings work, as reported in Building Design+Construction's 2022 Giants 400 Report.

Giants 400 | Aug 20, 2022

Top 180 Architecture Firms for 2022

Gensler, Perkins and Will, HKS, and Perkins Eastman top the rankings of the nation's largest architecture firms for nonresidential and multifamily buildings work, as reported in Building Design+Construction's 2022 Giants 400 Report.

Giants 400 | Aug 19, 2022

2022 Giants 400 Report: Tracking the nation's largest architecture, engineering, and construction firms

Now 46 years running, Building Design+Construction's 2022 Giants 400 Report rankings the largest architecture, engineering, and construction firms in the U.S. This year a record 519 AEC firms participated in BD+C's Giants 400 report. The final report includes more than 130 rankings across 25 building sectors and specialty categories. 

| Aug 19, 2022

Cuningham appoints Jacqueline Dompe as new Chief Executive Officer

Cuningham, a national design firm, is thrilled to announce the appointment of Jacqueline Dompe as the firm’s Chief Executive Officer (CEO). 

| Aug 19, 2022

Future sea rise could expose 720,000 more people on East Coast to flooding

An analysis by NPR based on modeling from the National Hurricane Center for New York City, Washington, D.C., and Miami-Dade County found future sea rise could expose about 720,000 more people to damaging floods later this century.

| Aug 19, 2022

Manassas Museum renovated to reimagine a civic design & engage the community

Manassas, VA has recently added to its historic Manassas Museum.

boombox1
boombox2
native1

More In Category




Resiliency

U.S. is reducing floodplain development in most areas

The perception that the U.S. has not been able to curb development in flood-prone areas is mostly inaccurate, according to new research from climate adaptation experts. A national survey of floodplain development between 2001 and 2019 found that fewer structures were built in floodplains than might be expected if cities were building at random.

halfpage1

Most Popular Content

  1. 2021 Giants 400 Report
  2. Top 150 Architecture Firms for 2019
  3. 13 projects that represent the future of affordable housing
  4. Sagrada Familia completion date pushed back due to coronavirus
  5. Top 160 Architecture Firms 2021