he Kimbell Art Museum has been the landmark of culture for the Fort Worth communi- ty since its opening in 1972. Designed by the distinguished American architect Louis Kahn,T the building brought natural light to art and sculpture and overdue respect to “Cowtown,” a city previously known for oil and cattle. As expansion plans were long studied, the Kimbell Art Foundation and the archi- tect priceless pieces of art from moisture. and quality-assurance observation services tectural community at large shared their Garden roofs atop portions of the expansion related to the building envelope, excluding concerns about any potential new structure project served to provide a landscaped the specially designed glass roof system). adjacent to the Kimbell that might detract space that would separate the old and new After a careful review of the well- from this hailed architectural gem. After structures, with a portion of the project crafted plans prepared by Kendall/Heaton many years of consideration, the Kimbell’s including a below-grade parking garage for Associates, Inc. of , , a con- board commissioned famed Italian archi- visitors. ference was held at the site. All parties tect Renzo Piano, who had been inspired A specially designed glass roof, complete involved with the waterproofing aspects by the Kimbell when he designed the Menil with photovoltaic solar panels mounted and certain critical details were involved as Collection in Houston—and more recently, on exposed Douglas-fir-laminated glue-lam part of the team’s overall goal of delivering a the in nearby beams, was carefully designed to bring leak-free facility to the Foundation. , Texas. appropriate amounts of diffuse natural light After this overall review, separate pre- Renzo Piano was very much aware of into the gallery spaces while reducing the installation conferences were held with each the challenges that existed when consider- overall heat island effect. of the building envelope-related subcontrac- ing a building sited next to Kahn’s iconic While the new building in no way mim- tors’ and manufacturers’ representatives. structure, and he developed a design con- ics the original Kahn structure, it clearly These included critical details, down to the cept that was greatly influenced by Kahn’s succeeds in satisfying the goals of the type of curing compound that could be used building while clearly embodying his own Kimbell Art Foundation, the architectural on poured-in-place concrete decks sched- design aesthetics. In addition, the major- community, and art patrons. uled to receive garden roof assemblies. ity of this new building would be situated The Beck Group, out of Dallas, Texas, The correct design and installation of underground. was chosen as construction manager for the below-grade waterproofing was of par- At 80 feet below grade, the new struc- this project. DryTec Moisture Protection amount importance for the success of the ture would cross paths with the Trinity Technology Consultants, Inc. (DryTec) was project, as the Trinity River Basin would River Basin. This reality presented water- chosen by Beck and the Paratus Group (the provide potentially significant hydrostatic proofing challenges that would need to be management firm engaged by the Kimbell pressure, depending upon the annual rain- incorporated into the design in order to pro- Foundation to provide peer design review fall amounts. Starting at the bottom of

n o v e m b e r 2 0 1 4 I n t e r f a c e • 3 7 Photo 1 – HDPE waterproofing.

Photo 2 – Steel reinforcing in piers.

the excavation, high-density polyethylene needed to carefully (HDPE) waterproofing was installed Photo( 1). fold the waterproof- The manufacturer’s required seam tape was ing membrane away adhered to the end laps, seams, and flash- from a concrete pour, taking care not to ings at grade beams, reinforced concrete ings to provide a continuous mechanical destroy the membrane, which would need piers, and expansion joints, with all such bond with the concrete cast upon it. Careful to be extended up and above at a later date installations being reviewed on the basis of inspection of this product was provided by to tie in with vertical below-grade water- approved submittals and manufacturers’ Drytec to supplement the oversight by Beck proofing. Careful inspection by all parties written instructions. Below-grade water- and the waterproofing subcontractor. also ensured that waterproofing membranes proofing demands a perfect installation to Coordination and cooperation among were not punctured during installation of prevent future costly remedial repairs. This, trades was essential. Concrete tradesmen steel reinforcing (Photo 2). coupled with a well-designed subsurface Custom details were prepared for flash- drainage system, has the new museum “in the dry.” On the vertical, meticulous prepa- ration of the concrete finish was exe- cuted to allow for proper adhesion of the chosen waterproofing membrane. All repairs to the sub-grade concrete walls were executed in conformance with ASTM D5295, Standard Guide for Preparation of Concrete Surfaces for Adhered (Bonded) Membrane Waterproofing Systems; and ACI 515, A Guide to the Use of Waterproofing, Dampproofing, Protective and Decorative Barrier Systems for Concrete; with a number of irregularities caused by rod holes, honeycombing, and rock pockets requiring additional attention. After the below-grade concrete had been properly prepared, the chosen prim- er was applied to the walls and allowed to dry. After this, a self-adhering waterproof- ing membrane (Photo 3) was fully adhered

Photo 3 – Self-adhering waterproofing membrane.

3 8 • I n t e r f a c e n o v e m b e r 2 0 1 4 Photo 4 – Modified asphalt with polyester reinforcement.

Photo 5 – Protection sheet.

to the walls, with careful oversight being to the installa- provided as noted previously. Prior to the tion of overbur- backfill being installed, a drainage mat and den and land- associated protection board were installed. scaping, flood A liquid-applied, vapor-permeable air/ testing was per- moisture barrier was installed after care- formed in areas ful review and consideration of all critical of concern and flashing details. At joints in the precast at minor deflec- architectural concrete panels, T-shaped tions in the pieces of the 24-ga. stainless steel sheet deck. With the metal were installed to bridge the joints in aid of this sys- the concealed spaces within the specially tem, leaks were identified and corrected as nyl chloride (PVC) cladding (Photo 6) were designed architectural concrete walls, with the work progressed. Some leaks were a lifted onto the 100-foot-long Douglas-fir small rollers being used to apply the flash- result of something as small as a piece of “glue-lam” beams (Photo 7). A series of ing membrane for this system. pea gravel penetrating the membrane, while photovoltaic solar panels are installed in A year and a half passed before it was others were due to more obvious damage a low-profile sawtooth-monitor fashion. time to install the green roofing systems. from other trades. Fritted glass and fabric scrims illuminate With the works of Picasso, Matisse, and Common gutters insulated with polyvi- other artists displayed directly beneath these roof decks, absolute perfection was essential. At the roof level (which is actually ground level), the architect of record chose to install a hot, modified-asphalt system. The concrete decks were primed with an approved material, followed by a hot mop- ping of modified asphalt with spun-bounded polyester reinforcement embedded in the hot bitumen (Photo 4). The temperature of the bitumen was monitored to meet equiv- iscous temperature (EVT) criteria during applications. The manufacturer’s protection sheet (Photo 5) was hot-mopped as a part of the installation after all surface defects in the concrete were properly addressed. To aid in the identification of any future leaks in the green roofing membrane, a Photo 6 – vector-mapping electronic leak detection Common system was specified and performed. Prior gutters.

n o v e m b e r 2 0 1 4 I n t e r f a c e • 3 9 Only one-third art and architecture.” of the interior of Visitors to this structure will experi- the Piano Pavilion ence art displayed amidst beautiful natural is above ground, wood floors, expertly executed architectural reducing heat- concrete walls, and diffuse natural light. ing and cooling Members of the design and construction demands. Because team will most likely be thinking about of its below-grade the critical waterproofing issues that were co ns t r uc t i o n— solved as a part of this project. coupled with solar panels and Keith Simmons has 460-ft.-deep geo- been a Registered thermal walls—the Roof Observer Piano Pavilion will with DryTec Mois- use half the ener- ture Protection gy required for the Technologies for operation of the the past nine Kahn Building. years. Prior to that, Photo 7 – Douglas-fir “glue-lam” beams. Original crit- he was a roofing ics of this addition contractor in the the silvery sheen of the exposed concrete have hailed the expansion as a success. “No North Texas area walls, which contain 2% titanium additive Harm to the Kimbell,” wrote architecture Keith Simmons, RRO for 23 years. He in the concrete mix. A German-based con- critic Martin Fuller. Further comments has been a member of RCI since 2005 and tractor fabricated the specially designed were, “does no harm to the adjacent land- a participating member of its North Texas glass roof. mark,” and, “a warm embracing fusion of Chapter since its inception.

The RCI Foundations – CONSTRUCTION BACKLOG HITS Supporting The Industry RECORD HIGH

The Associated Builders and Contractor’s (ABC’s) measure of its members’ backlogs for new work reached an all-time high during the second quarter of this year. The Construction Backlog Indicator (CBI) hit 8.5, up 5.6% from the first quarter and 3.6% above the second quarter of 2013. “Gains [were] registered in every industry segment in nearly all geographies and for firms of virtually all sizes,” reported Anirban Basu, ABC RCI Foundation – United States RCI Foundation – Canada chief economist. The increases are likely due to job growth and Web site: www.rcifoundation.org Web site: www.rcifoundation.ca rising consumer confidence, Basu E-mail: [email protected] E-mail: [email protected] reports. — ENR

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