Building Envelope Investigation UTHSCSA - CTRC. San Antonio, Texas. June 20, 2016

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1 DRAFT DRAFT Building Envelope Investigation At UTHSCSA - CTRC San Antonio, Texas June 20, 2016 Zero/Six Consulting, LLC 2550 S. IH-35 Ste. 215 Austin, Texas z6consulting.com

2 Table of Contents TAB 1 TAB 2 TAB 3 TAB 4 Table of Contents Project Data/Synopsis Executive Summary Photographs Page 2 Pages 3 Pages 4-6 Pages 7-16 Draft Report Prepared By: Bart Tate Zero/Six Consulting, LLC Tab ZERO/SIX UTHSCSA - CTRC Page 2

Tab 2 General Information Project: Address: Owner: Client: CTRC 7979 Wurzbach San Antonio, Texas 78229 UTHSCSA Mr.

3 Tab 2 General Information Project: Address: Owner: Client: CTRC 7979 Wurzbach San Antonio, Texas UTHSCSA Mr. Dan Parker ZSC Field Crew: Report Authors: Kelly Mitchell Niles Varney Bart Tate Miguel Hernandez Bart Tate Project Data Construction Team: Project Manager: Architect: CM: NA NA NA NA Design Code: Wind Speed: Importance Factor: Exposure: Unknown Unknown Unknown Unknown Year Built: Building Use: Storm Damage: Fire Damage: Clinical No No Levels above grade: High Rise by Code: Levels belowgrade: Approximate SF: 6 No 0 327,000 Project Synopsis The subject of this report is the leak investigation of the University of Texas Health Science Center San Antonio - Cancer Therapy & Research Center (CTRC). Zero/Six Consulting (ZSC) has been commissioned by UTHSCSA to perform an investigation of several conditions that have been experiencing ongoing water infiltration. The goal of this exercise is to develop recommendations for remediation to mitigate ongoing water infiltration. The CTRC complex consists of multiple contiguous buildings built between 1995 and These are comprised of the Urschel Tower, the Grossman Building and the Zeller Building. A multi-story parking garage is connected to the Urschel tower via an open air sky bridge. ZEL GRO All buildings can be generally described as mid-rise concrete framed structures with low-slope roofs. Grossman and Zeller have similar exterior finishes that consist primarily of architectural precast concrete panels and single glazed (non-insulated) aluminum curtain walls. Urschel is clad with URS EIFS (exterior insulation and finish system) and mix a of single glazed aluminum curtain wall and punched windows. ZERO/SIX UTHSCSA - CTRC Page 3

Tab 3 Executive Summary ZSC conducted an initial review of the building with site personnel to identify the locations of water infiltration that impact building operations the most.

4 Tab 3 Executive Summary ZSC conducted an initial review of the building with site personnel to identify the locations of water infiltration that impact building operations the most. This included approximately four unique areas where significant water intrusion was occurring. Based on these findings ZSC used a variety of diagnostic water tests methods in an effort to determine the source of water infiltration. It should be noted that ZSC conducted visual observations of locations outside of the primary survey and discovered evidence of further water infiltration. Urschel: Areas of focus on the Urschel Tower included windows of patient rooms in the fourth floor hematology clinic along the east elevation. This included three rooms, two of which had punched windows and one located within the glazed aluminum curtain wall system. The area within the curtain will be referenced as URS.1 for and punched window locations referenced as URS.2 and URS.3 for reporting purposes. Prior to any water testing, the area around URS.1 was inspected for any obvious deficiencies that could be allowing water intrusion. It was apparent that past attempts had been made to correct water infiltration by wet glazing of the curtain wall. This a common remedial technique which involves sealing over the existing exterior gasketing. The wet glazing that had been done, appeared to be applied adequately but was only installed around a few of the glass panels. At adjacent areas where this had not been done, issues were noted that could potentially be the source of water entering the building. These items are described further in Tab 4 of this report. At URS.1 we were able to recreate water infiltration by placing a 8 x 10 water spray rack above the location of reported water infiltration and soaking the curtain wall at different points above the affected room for approximately 45 minutes. It was not until after this time that water was observed entering the building. This was attributed to the fact that there are at least three spandrel panels (non-vison glass panels that are insulated with mineral fiber) above the room that keep water from being readily noticeable. Water infiltration was also discovered on the level below at room U345. After water intrusion was recreated with a spray rack, the roof edge above the curtain wall (a suspect area) was thoroughly sprayed with a calibrated nozzle and no additional water entered the building. Based on these results it is evident that the curtain wall itself is contributing to water infiltration around the affected area. Additional contributing factors including the roof above could not be verified at this time but there is some evidence (dark brown water stains on the windows) to suggest that the roof is a secondary source of water infiltration. At this time, ZSC recommends that all exterior gaskets along the curtain wall are wet sealed with care taken not to restrict any of the weeps at the underside of the face caps. Further investigation of the roof and parapet flashings above are recommended if wet sealing the curtain wall does not fully mitigate water intrusion. ZERO/SIX UTHSCSA - CTRC Page 4

After no water was discovered the spray rack was moved up above the windows to soak the EIFS cladding between floor levels.

5 Executive Summary The test strategies used at URS.2 and URS.3 were identical. We started off by placing a spray rack directly in front of the affected windows and soaking the exterior for approximately 20 minutes. After no water was discovered the spray rack was moved up above the windows to soak the EIFS cladding between floor levels. It was not until the spray rack was positioned directly in front of the level five window that water intrusion was recorded at level 4. Additional investigating was conducted via chamber testing at the subject windows. This procedure utilizes a calibrated spray rack that is positioned on the exterior face of the window while a chamber from the interior is depressurized under static pressure to recreate wind driven rain. Each of the windows tested were subjected to increasing loads for a period of 20 minutes. The final test load reached was 3in/h 2 o. This equates to > 15 PSF which is more than the performance rating of most modern glazing systems. In other words, the windows themselves are performing fine and it is clear that water is entering through the wall not through the windows. Closer investigation of the conditions at URS. 2 & URS.3 revealed deficiencies at the EIFS lamina, the exterior shell that forms the waterproofing layer of the system. Examples of these issues can be seen in Part 4 of this report. Since the perimeter sealant joint of the window seal directly to the EIFS with no sub flashing, any water that defeats the EIFS shows its self at the window opening. The photo to the left, taken from inside the building, shows this condition. Remediation of this condition will involve the application of an elastomeric coating to the EIFS system and likely replacement of all perimeter seal around punched windows to ensure full continuity of the drainage plane. Zeller: At the Zeller building the area of focus was the Balcony feature adjacent to rooms Z548 and Z555. This feature is not truly a balcony (and not accessible from inside the building) but likely an extension of the building structure that is meant to accept a possible future sky bridge from the lot across the street. Water infiltration was reported at the level directly below where the lower portion of the balcony interfaces with the building. The depth of the roof area below did not allow for direct aerial lift access to this area so visual observations had to be conducted from inside the building at level six. No conclusive issues could be seen from inside but water infiltration was easily recreated when the spray rack was positioned just adjacent to either side of the lower projection seen in the photograph above. Water could be seen running down the inside of the vertical window mullions within approximately 3 minutes of soaking each area. Based on this, it is very likely that the source of water infiltration here is sealant detailing that has failed. Specialized equipment will be needed to access this location and to make more specific recommendation for repair. Any issues should be readily visible based on the short duration it took to produce water intrusion. ZERO/SIX UTHSCSA - CTRC Page 5

Executive Summary Grossman: The area of focus at the Grossman Building was located within room G355. Evidence of water damage at this location was minor compared to the previous locations.

6 Executive Summary Grossman: The area of focus at the Grossman Building was located within room G355. Evidence of water damage at this location was minor compared to the previous locations. The affected area was at the third level of a section of glazed aluminum curtain wall that spans from the grade to level four. ZSC began testing this area by hanging a spray rack, approximately 6 x 8, over the roof above. The spray rack was first positioned directly at the area of water infiltration for 20 minutes. After no water penetration was observed the spray rack was moved up the wall. This continued until the spray rack was located entirely above the window system and the precast concrete panels were subjected to a direct soaking from the spray rack. It was at this point that the leak was recreated. Visual observation from the roof above confirmed that the sealant joint between precast panels had failed at this location allowing water to accumulate within the wall (no weep system was visible) and eventually showing up at room G355. ZSC recommends that all soft joints above this section of curtain wall are removed and replaced with dual sealant joint in which a weep is incorporated at the bottom of all vertical joints. Additional Commentary: During our review of the areas pointed out by building personnel, and described in detail above, it was apparent that these where not the only areas where water intrusion is occurring. Although ZSC did not have full access to the building, at many areas ZSC did notice evidence of ongoing water infiltration. Several of these areas were noted along the east elevation of the Urschel Tower, supporting our conclusion of water defeating the EIFS system here. At the Zeller and Grossman buildings many of the sealant joints between the architectural precast panels had failed or were beginning to degrade to the point of failure. These joint are urethane based sealant which typically has a service life of years. ZSC recommends that a thorough survey of the entire CTRC complex is conducted in order to develop a full repair scope. This should prioritize items based on immediate impact to the building and additionally develop a list of items for repair/ maintenance that should be budgeted on the short-term future. End of Summary ZERO/SIX UTHSCSA - CTRC Page 6

Tab 4 Photographs General overview sample areas were water testing and trouble shooting was conducted.

1, 2 & 3 Urschel Tower 1 This photo was taken from above the ceiling tile at URS.1 during our initial visit.

it had not been wet glazed highlighted deficiencies which include gaps on the exterior glazing gaskets.

7 Tab 4 Photographs General overview sample areas were water testing and trouble shooting was conducted. From left-to-right locations are noted as URS.1, 2 & 3 Urschel Tower 1 This photo was taken from above the ceiling tile at URS.1 during our initial visit. Biological growth is indicative of long-term water infiltration Urschel Tower 2 Inspection of the curtain wall, where it had not been wet glazed highlighted deficiencies which include gaps on the exterior glazing gaskets. This material, EPDM rubber, shrinks over time and when exposed to UV. It appears that sealant has been added at many of the points but further shrinking of the gasket has allowed for voids. Urschel Tower 3 ZERO/SIX UTHSCSA - CTRC Page 7

Shrinkage of exterior glazing gaskets has occurred at much of the Urschel curtain wall.

the curtain wall we noticed open vent holes.

8 Shrinkage of exterior glazing gaskets has occurred at much of the Urschel curtain wall. A full wet glazing of the wall is recommended Urschel Tower 4 Overflow scupper through the curtain wall panel infill needs to be removed and resealed. This location appears to be contributing to water infiltration Urschel Tower 5 At the hand rail along the roof edge above the curtain wall we noticed open vent holes. These holes are used for the galvanization process to allow the inside of the steel to be coated but are notorious for allowing water infiltration. Wind striking the face of the wall below can cause an updraft carrying rain into these areas. All vents should be sealed with a lead plug. Urschel Tower 6 ZERO/SIX UTHSCSA - CTRC Page 8

Seal al vent holes in hand rail The roof edge flashing above the head of the curtain wall appeared to be well detailed

Urschel Tower 7 Although no obvious issues could be seen with the roof flashings above the curtain wall.

This is based on the dark brown water stain on the windows that are consistent with water containing asphalt residue.

9 Seal al vent holes in hand rail The roof edge flashing above the head of the curtain wall appeared to be well detailed and underside was fully sealed to the face of the window. Urschel Tower 7 Although no obvious issues could be seen with the roof flashings above the curtain wall. This area cannot be ruled out as a contributor to water infiltration below. This is based on the dark brown water stain on the windows that are consistent with water containing asphalt residue. Urschel Tower 8 During testing of the curtain wall water was discovered at level three. This location was not know to us to be a problem area but based on damages to finishes this area appears regularly leak. Urschel Tower 9 ZERO/SIX UTHSCSA - CTRC Page 9

Inspection of the exterior wall around the punched windows revealed issues

finish Urschel Tower 10 Approximately 1/16 crack noted in EIFS.

assembly and there a no means to weep water out once this happens.

10 Inspection of the exterior wall around the punched windows revealed issues at the EIFS are very likely contributing to water infiltration Void in EIFS finish Urschel Tower 10 Approximately 1/16 crack noted in EIFS. Although minor this type of issue will allow water to enter the wall assembly and there a no means to weep water out once this happens. Urschel Tower 11 Reinforcement mesh visible at EIFS Urschel Tower 12 ZERO/SIX UTHSCSA - CTRC Page 10

At one of the punched windows the interior sealant joint was partially removed and it was noted that the window was

In this scenario and water that enters the wall assembly will be forced into the building at the window openings.

On the east elevation of Urschel Tower. This location was not one of the areas of primary focus.

11 At one of the punched windows the interior sealant joint was partially removed and it was noted that the window was sealed directly to the EIFS as expected. In this scenario and water that enters the wall assembly will be forced into the building at the window openings. Urschel Tower 13 An active leak was observed at the level three punched windows. On the east elevation of Urschel Tower. This location was not one of the areas of primary focus. Urschel Tower 14 This area was not reported to be an active leak but based on the amount of mineral deposits from past leaks our thought that water is a result of leakage through the EIFS is supported. Urschel Tower 15 ZERO/SIX UTHSCSA - CTRC Page 11

Evidence of water damage observed at level 2 of the east elevation

Urschel Tower 16 Areas of reported water infiltration at the Zeller

able to access the exterior of the balcony.

12 Evidence of water damage observed at level 2 of the east elevation (EIFS Wall). Urschel Tower 16 Areas of reported water infiltration at the Zeller Building along level 5 are highlighted in red Zeller 17 ZSC was not able to access the exterior of the balcony. Based on what could be seen from level 6 the landing appears to incorporate a deck coating on a portion of the area. Zeller 18 ZERO/SIX UTHSCSA - CTRC Page 12

Water infiltration was recreated by placing a spray rack directly adjacent to the

Water entered the building in less than 5 minutes Zeller 19 The opposite side of the

Zeller 20 This photo is unrelated to the water infiltration occurring at north

13 Water infiltration was recreated by placing a spray rack directly adjacent to the lower portion of the balcony. Water entered the building in less than 5 minutes Zeller 19 The opposite side of the balcony was then tested with similar results. Zeller 20 This photo is unrelated to the water infiltration occurring at north elevation of level 5 but sealant joints within the precast concrete panels have failed in many areas. This condition was observed along the plaza at level 5.. Zeller 21 ZERO/SIX UTHSCSA - CTRC Page 13

Additional sealant failures documented along the plaza between Zeller and

intrusion at room G355 Affected area highlighted in red Grossman 23 The glazing

It was not until the spray rack was positioned entirely on the precast panel

14 Additional sealant failures documented along the plaza between Zeller and Grossman Zeller 22 Water spray rack in place during investigation of water intrusion at room G355 Affected area highlighted in red Grossman 23 The glazing system was soaked at the various points directly above this area. It was not until the spray rack was positioned entirely on the precast panel above the curtain wall that water infiltration was recreated. Grossman 24 ZERO/SIX UTHSCSA - CTRC Page 14

This sealant joint that has failed resulted in water entering

This area observed was outside of the test locations but is an

15 This sealant joint that has failed resulted in water entering the building and can be seen in the previous photo Grossman 25 This area observed was outside of the test locations but is an example of the poor shape of joint sealants on both the Zeller and Grossman buildings. Grossman 26 Another example of joint sealant that has failed. Grossman 27 ZERO/SIX UTHSCSA - CTRC Page 15

16 Significant water damaged was observed in Stair 3 of the Grossman building. Additional investigation is need to determine the source Grossman 28 End of Report Electronic Copy ZERO/SIX UTHSCSA - CTRC Page 16

Margaret Batts Tobin Laboratory

Roof Evaluation of Margaret Batts Tobin Laboratory The University of Texas At San Antonio Performed for UTSA Zero/Six Consulting, LLC 8423 Stewart Road Galveston, Texas 77554 409 740 0090 voice Table of