Cal-Neva Casino Parking Structure 1 East First Street Reno, Nevada

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1 1 East First Street Reno, Nevada DUE DILIGENCE CONDITION ASSESSMENT BY: FOR: Carl Walker, Inc. City of Reno 1920 S. Highland Ave. 1 East First Street Lombard, IL Reno, Nevada 89505

2 John Flansberg Director of Public Works 1 East First Street, 7 th Floor Reno, Nevada Re: Carl Walker, Inc. Project R Dear Mr. Flansberg: Carl Walker, Inc. has completed the evaluation of the located adjacent to the Cal-Neva Casino and City Hal and at 1 East First Street in Reno, Nevada. This letter provides a general discussion on the condition of the garage structure and recommendations for its repair and maintenance. Included with the report are estimated financial projections for recommended repairs and maintenance for the garage over the next 10 years. EXECUTIVE SUMMARY The is approximately 48 years old, and was found to be in fair to poor condition for a structure of its age and construction type. The structure was apparently built in two phases, with Levels 6 and 7 added as an addition after the construction of the original 5 levels. Levels 5 and 7 were constructed as the roofs for each phase utilizing a waterproofing membrane on the structural slab covered by a concrete wear course. Excessive cracking of the structural slab was identified at levels 2, 3, and 4. The location and distribution of the cracks indicates they may be the result of a possible overstress. Additional testing is required in order to determine if there is an overstress of the slabs as well as identify the root cause of the cracking. The concrete topping at Level 7 was found at some deteriorated areas to be only 1½ inches thick, although the original design drawings specified a 2¾-inch topping, and exhibited significant cracking and freeze-thaw damage. The topping slab on Level 5 was generally in good condition. The Cal-Neva parking structure requires immediate repairs in order to restore the structure. Immediate repairs include items such as slab repairs to the parking areas and ramps and installation of a new deck coating to the slab surfaces for a total estimated cost of $1,195,000. For a full list of recommended repairs, refer to the Capital Reserve Analysis provided at the end of this report

3 SCOPE OF SERVICES The scope of services for the evaluation of the parking structure included the following: 1. Review of existing documentation including original design drawings, specifications, previous evaluation reports, maintenance records, and other documents, as available. The following document was available for our review: a. Design drawings, some labeled as ADDITION TO and variously dated between September 30, 1963 to September 1, 1965, as prepared by Langdon & Wilson, Architects, of Los Angeles, California, with sub-consultants Ferris, Erskine & Calef, Associated Architects; Brandow & Johnston, Structural Engineers, William H. Ades, Electrical Engineer, and John C. Freeman, Mechanical Engineer. b. Evaluation report dated August 3, 2010 as prepared by Tobey Wade Consulting of Reno, Nevada. 2. A visual review of the floors, columns, beams, walls and other exposed structural elements for cracking, leaks, spalls (potholes), scaling, corrosion, joint sealant failure, and coating system condition. 3. A limited visual review of other components including the floor slab drainage system, stairs, and similar construction to determine their general condition. 4. Perform a non-destructive chain-drag sounding of representative areas of the supported parking slabs to identify/quantify top-of-slab delaminations. 5. Prepare a letter report (with photographs) of our evaluation that will explain the general conditions, present a work item list of recommended repairs and their probable construction costs. Costs are provided for current recommended repairs as well as a 10-year present value outlook for which the Owner can plan and budget

4 STRUCTURE DESCRIPTION The structure is approximately 48 years old and consists of 7 supported parking levels with a slab-on-grade basement level used primarily by the Cal-Neva Casino for storage, mechanical equipment, and building engineering work space. Originally built as a stand-alone structure for the formerly First National Bank of Nevada located west of the garage, the Cal Neva Casino was constructed adjacent to the north side of the structure. Elevators at the north end and direct access to the casino were added in the mid-1980 s when the Cal Neva Casino purchased the garage from the First National Bank. The First National Bank is now owned and occupied by the City of Nevada. The overall dimensions of the structure are approximately 190 feet in the north-south direction and 140 feet in the east-west direction yielding a total of approximately 185,000 square feet of supported floor area and approximately 25,000 square feet of slab-on-grade. Two adjacent speed ramps along the west wall, one for entering (up) and one for exiting (down), provide access for each flat deck level. Street access is from the north end of the east side and exits are located at the south end of the east side and west end of the south side. The structural system is composed of conventionally reinforced cat-in-place concrete twoway slab and joist (waffle slab) system. Slab spans between columns vary from 26 to 38 feet with cantilevers on the east and south sides that are 8 and 14 feet respectively. The speed ramps are one-way slabs spanning 11 feet between one-way beams supported on the ramp walls space at 15 feet. The parking structure utilizes 90 degree parking throughout the garage. The structure provides approximately 442 parking spaces for a rather low efficiency of 420 square feet per space. The designated clearance height is 6-8 at the entrance, which will not allow accessibility vans to use the garage. There are two emergency exit stair towers that service the parking structure located at the northeast and southwest corners of the structure. Two elevators are located at the southwest corner as well

5 STRUCTURE SUMMARY STRUCTURE NAME: LOCATION: 1 East First Street Reno, Nevada YEAR BUILT: Basement to 5 th Floor: th & 7 th Floors: 1966 CONSTR. TYPE: CONCRETE: Structural: Topping Slab: Conventionally reinforced CIP concrete two-way slab and joist (waffle slab) system. Normal weight, 3,000 PSI Lightweight, 3,000 PSI REINFORCING STEEL: Columns: Slabs, Beams & Joists: 60,000 PSI. 40,000 PSI SPANDRELS: EXTERIOR WALLS: EIFS over Concrete Painted Concrete # OF LEVELS: On-Grade (Bsmt. Storage): 1 Supported (Levels 1 thru 7): 7 Total: 8 FIRE EXIT STAIRS: Two (2) ELEVATORS: Two (2) at SW corner + Two (2) at NW for the Casino. FLOOR AREAS: Slab On Grade: 25,000 SF 7 Supported Levels: 168,000 SF Ramps: 17,000 SF TOTAL: 210,000 SF PARKING SPACES: Standard: 428 Accessible: 14 Total: Motorcycle WATERPROOFING: Urethane Joint Sealants Traffic-Bearing Membrane on exposed surface of Levels 1-7 Waterproofing Membrane between topping and structural slabs at Levels 5 & 7-4 -

6 FIELD OBSERVATIONS On July 6 and 7, 2012, Carl Walker, Inc. completed a condition assessment of the Cal-Neva Casino Parking Structure. Item numbers noted below correspond to the repair and maintenance items on the Capital Reserve Analysis table. The following is a summary of our observations: CONCRETE ITEMS To assess the condition of the supported floor slab we performed a chain drag survey in accessible areas to locate and quantify delaminations. Much of the chain drag sounding was performed on Saturday when the municipal employees were not parking in the garage, but cars were parked throughout most of the lower levels the entire time of our survey work and Level 2 was always full. For reference, a delamination is a horizontal fracture beneath the concrete surface that is generally caused by corrosion of the embedded steel reinforcement or other embedded items. Rust, which is the byproduct of the corrosion process, has a volume several times that of the original steel. The volume change created by corrosion generates pressures on the surrounding concrete that eventually becomes sufficient to cause internal fracturing of the concrete and the loss of bond of the corroded reinforcing steel with the surrounding concrete. Once a comprehensive concrete repair and waterproofing program is completed, minor maintenance type repairs should be anticipated every 5 to 7 years. C1 Top of Slab Delaminations The chain drag survey indicated that concrete floor cracking and delaminations most commonly occur within the north-south column strips, which are approximately 20 foot wide bands of deck that are centered on the column lines. These areas primarily lie below the parking stalls and have greater top surface tensile stresses and are more heavily reinforced with steel near the top surface than at the center areas of the bays

7 C1 Top of Slab Delaminations (continued) Levels 2, 3 and 4 contain significantly more deterioration than Levels 1 and 6. The condition of the structural decks at Levels 5 and 7 are unknown since they are covered by waterproofing and a topping slab. The structural slabs at Levels 2, 3, and 4, and to a lesser extent at Level 6, exhibit excessive radial, and some circumferential, cracking around many of the columns indicating possible flexural or punching shear overstress. Parallel cracking along the column strips, particularly along the eastern and southern row of exterior columns, also indicates possible flexural overstressing of the deck. These conditions may be caused by improper design, construction deficiencies, and/or significant corrosion of the embedded reinforcing steel. We recommend additional investigation to include a structural analysis of the original design, examination of slab excavations, and in-situ and laboratory testing of the concrete, to determine the cause(s) of the excessive cracking. C2 Full-Depth Structural Slab Repairs The concrete structural slab is only 4 to 4½ inches thick between the joists (i.e. ribs) of the waffle slab, which will require that the entire depth of the slab will need to be removed between joists and replaced to provide a proper and effective repair. In a few isolated areas, the slab can be seen lifting off the joists from the expansive forces of the corroding steel reinforcement. The 10 to 12- foot roughly square shear caps around the columns are much thicker and will not require full-depth repairs

8 C3 Joist Deterioration The stems of the two-way joists are cracked and delaminated at limited areas of the garage. Most of the joist stem deterioration occurs along leaking construction joints and along the south edge of the garage. C4 Beam Deterioration The speed ramps along the west end of the garage are constructed of one-way slabs supported by concrete beams that span between the walls of the ramps. Most of these beams are in good condition, but we did observe cracking and deterioration of some of the beams, primarily near the bottom of the ramps. C5 Wall Deterioration The concrete walls and columns are generally in good condition with only a few isolated small areas of deterioration. Many areas of the walls have peeling paint, but the concrete remains in good condition

9 C6 Concrete Topping at Level 5 Level 5 was originally constructed as a roof deck.. Level 5 utilizes a waterproofing membrane on the structural slab covered by a concrete wear course. The concrete topping is reinforced with welded wire fabric (i.e. mesh). The topping slab on Level 5 was generally in good condition except for a few isolated deteriorated areas and widespread cracking, particularly over the steel wires of the mesh. We observed no evidence that water is leaking through Level 5, indicating that the waterproofing membrane is likely in good condition and still functioning well. The topping slab is not structural and serves to provide a durable driving surface and protection for the waterproofing membrane. Until the cracks develop into broken and loose pieces and become tripping hazards, we do not recommend repairs. We do not recommend re-coating the trafficbearing membrane at Level 5 as this will slow the evaporation of moisture that could become trapped between the waterproofing layers and accelerate the deterioration of the topping slab. C7 Concrete Topping at Level 7 Like Level 5, Level 7 is constructed as a roof deck utilizing a waterproofing membrane on the structural slab covered by a concrete wear course. The concrete topping contains widespread and significant cracking, heaving, and freeze-thaw damage. Most prior attempts to patch and repair the topping slab have failed. At some areas where the topping could be removed by hand, we found it to be only 1½ inches thick, although the original design drawings specified a 2¾-inch topping

10 C7 Concrete Topping at Level 7 (continued) The thin topping slab on the waterproofing membrane at Level 7 will likely continue to crack and deteriorate. Only complete removal and replacement of the topping slab will provide a more permanent solution. We recommend replacing the waterproof membrane and topping slab with a concrete overlay bonded to the structural slab, and the application of a top surface-applied trafficbearing membrane. We suggest applying the deck coating a year after placing the overlay to allow a longer curing of the concrete and the treatment of any shrinkage cracks prior to coating the deck. We do not agree with the recommendation of Tobey Wade Consulting to re-apply a trafficbearing membrane over the existing or repaired topping slab as it may trap moisture between the waterproofing systems which will promote freeze-thaw deterioration of the concrete and generally cause the coating to fail

11 WATERPROOFING ITEMS Parking structures require regular repair and maintenance of the various waterproofing systems to prevent ingress of chloride-contaminated water and minimize leaks within the facility. The following is a list of specific waterproofing items noted during our evaluation that require repair, maintenance, or new application: W1 Cracks and Construction Joints Cracking of the concrete slab and open construction joints allow salt-laden water to penetrate into the concrete and promote corrosion of the reinforcing steel. Some of the cracks, but particularly the unsealed construction joints allow water to penetrate through the slab and drip on vehicles or cause deterioration of the concrete joists. Routing and sealing of slab cracks is essential for protecting the structure against ongoing deterioration. W2 Slab Perimeter/Penetration Joints Joint sealants at the perimeter of the concrete decks, around columns, and at penetrations through the slab, have failed or are nonexistent. These joints should be caulked (known as cove sealants) to prevent water penetration and is recommended as part of the traffic-bearing waterproof membrane system

12 W3 Traffic Coating A traffic-bearing waterproof deck coating has been applied to all levels, except the basement. Most of the levels have 2 or 3 different coatings: some appear to be a neoprene-based membrane with an epoxy topcoat (also known as Kelmar), while others appear to be urethane based or top-coated. Some areas, particularly Level 1 and many of the drive aisles, have multiple layers of coating. None of the coated areas were flashed up the perimeter walls, around the columns, or at slab penetrations as generally recommended by industry standards. Nearly all of the drive aisles, and especially the turning radii, are worn down to the base coat or bare concrete. The membrane is peeling from some areas of the deck, particularly at Level 7, which should not have been coated for reasons explained earlier. Following the concrete repairs, all levels, except 5 and 7, should have loose, poorly bonded, and excessively thick areas of the deck coating removed, and a full heavy-duty deck coating system applied. Maintenance of the deck coating should include repairs to damaged areas as they occur and re-coating as the membrane wears. We would anticipate re-coating will be needed every 10 to 15 years in the parking stall areas, 7 to 10 years in the drive aisles, and 5 to 8 years at the turning radii

13 FAÇADE AND FINISHES F1 Level 1 Storefront The South and East sides of the garage at Level 1 are enclosed with an aluminum storefront system. Several of the mullions are buckled from the pressure of the deflection of the Level 2 cantilevered deck. Several sections of glass are missing and were likely broken from the pressure bearing down on the edge of the glass. We recommend removing the storefront system and installing a vehicular barrier system, and perhaps an alternative screen or other façade system. F2 Spandrels The South and East Elevations of the garage have concrete spandrels that appear to be clad with a synthetic stucco finish system. The finish appears to be in good condition with only small isolated area of damage. The repair and painting of the exterior can be deferred for a few years, and should be reviewed, repaired and painted approximately every 7 to 10 years as part of an ongoing maintenance program for the garage. F3 West Concrete Wall The West Elevation of the garage is enclosed by a concrete wall which is in fair to good condition. We recommend concrete repairs and painting the wall within the next 3 to 5 years, with periodic repairs and painting anticipated to be needed every 7 to 10 years

14 F4 Stair Tower Finished The finishes on the doors, wall and railings of the stair towers are in fair to good condition and will require periodic repair and painting. Isolated damage was observed on some of the finishes and should be repaired and touched-up as needed. F5 Garage Ceiling, Wall and Column Finishes The garage ceiling, walls and columns are painted in a bright, highly reflective white paint that provides the parking structure a clean and safe appearance. The finishes are generally in good condition with isolated areas of peeling or damage from leaks. Maintenance of the surface finishes at approximately 7 to 10 year intervals is recommended. ROOFING R1 Stair Tower Roofs We did not have access to the northeast corner stair tower roof, but we could observe it from a distance from the elevator tower roof and the parking structure across the street. We were able to access the southwest stair tower roof. Both roofs of the stair towers appear to have exceeded their useful life and are in poor condition. The fasteners were protruding from the southwest stair roof and had punctured to membrane in a few locations. Both roofs should be replaced within the next 2 years

15 PLUMBING ITEMS P1 Floor Drains and Piping The concrete around many of the drains is deteriorated which makes the condition of the drain bodies suspect. We would anticipate that the drain bodies will need to be replaced during the concrete repair work. Piping appears to be in good condition from the appearance of their exterior surfaces. P2 Supplemental Drains Slab staining indicates several areas of ponding water, particularly on Level 7. Spacing between some of the drains is excessive and the installation of a supplemental floor drain at these areas is recommended to minimize the size and number of ponding areas. MISCELLANEOUS ITEMS M1 Fall Protection in Stairwells Current life safety codes require that railings for fall protection not have any openings in them large enough for a 4-inch diameter sphere to pass through. We recommend upgrading the non-compliant railings with new railings or custom fabricated wire screen panels

16 DISCUSSION AND RECOMMENDATIONS The structural slabs at Levels 2, 3, and 4 exhibit excessive radial, and some circumferential, cracking around many of the columns indicating possible flexural or punching shear overstress. Parallel cracking along the column strips, particularly along the eastern and southern row of exterior columns, also indicates possible flexural overstressing of the deck. Significant cracking and delamination of most column strip areas of the deck indicates corrosion of most of the top layer of reinforcing steel in the slab. These areas primarily lie below the parking stalls. The deterioration is more severe and extends to the middle strip (i.e. areas below the drive aisles) of some areas of Level 2. The conditions described at Levels 2, 3, and 4 may be caused by improper design, construction deficiencies, and/or significant corrosion of the embedded reinforcing steel. Therefore, we would recommend additional investigation to include a structural analysis of the original design, examination of slab excavations, as well as in-situ and laboratory testing of the concrete, to determine the cause(s) of the excessive cracking. Level 6 contains similar conditions, but to a far lesser extent. Since Level 6 was designed similarly to the other levels, we suspect that the quality of construction may be the underlying cause of the conditions identified at the other levels. Level 1 is constructed slightly differently in that the east and south perimeter of the deck is supported on the basement walls, thus eliminating the stresses caused by the cantilevered decks that are typical at the remaining levels. The lower stresses and better condition of the deck membrane have helped to minimize the deterioration of Level 1. The condition of the structural decks at Levels 5 and 7 are unknown since they are covered by waterproofing and a topping slab. We would anticipate that the buried waterproofing layer has protected the structural slab from de-icing salts and moisture except at the locations where leaks through the deck were observed. The estimated quantity of structural slab repairs at these two levels is based on a portion of the observed topping slab deteriorated slab area and areas with evidence of leaks through the deck. The actual amount could be significantly greater. Conditions identified during our evaluation require near-term attention and further engineering analysis to correct and repair deficiencies and deterioration. In no particular order, the most notable items include: Concrete delaminations at each level or ramp, as a percentage of total floor area: o Level 1: 4% o Level 2: 50% o Level 3: 44% o Level 4: 32% o Level 5: 3% of topping slab, structural slab is hidden o Level 6: 7% o Level 7: 43% of topping slab, structural slab is hidden o Ramps: 15%

17 Excessive radial cracking in the concrete slab around many of the columns. Severe deterioration of the concrete topping slab at Level 7. Worn waterproof deck coating at all levels of the garage. Stair railings at the exit stairs that do not comply with current fall protection requirements (4-inch diameter sphere should not be able to pass through the railings). Stair tower roofs that have exceeded their useful life. Corroded floor drains. Inadequate deck drainage (ponding water). Failing storefront (bowed mullions due to deflection of Level 2 cantilevered deck. We suggest prioritizing the required maintenance and capital improvements based on the following criteria in order of importance: 1. Life safety, especially tripping hazards. Level 7 should be restricted from the public until it is repaired. 2. Severity of deterioration, especially where it may be affecting structural integrity. 3. Repair of entire levels at a time for efficiency and economy of scale. A temporary drive lane will need to be provided through the level to access the other levels. 4. Repair of multiple adjacent levels at a time, again for the greatest efficiency and economy of scale. Repairs at a particular level will require the closure of the level immediately below that level for full-depth repairs, shoring, and safety from falling debris. 5. Waterproofing and other protective measures to extend the life of the structure. 6. Aesthetic improvements, such as painting

18 Using the above criteria, repairs to address current deterioration and distress can be spread over 4 years as follows: Immediate Repairs should focus on evaluating the cause of the observed structural distress (i.e. slab cracking) and the repair of Level 2 since it has the greatest deterioration. We suggest including the repair and waterproofing of Level 1 since it will need to be closed (except for access lanes to the upper levels) for Level 2 repairs. Immediate Repairs should also include the removal of the failing storefront system and installation of vehicular barrier system at Level 1. Year 2 repairs should address the significant deterioration at Levels 3 and 4, and include the waterproofing of Levels 2, 3 and 4 to extend the useful life of the repaired levels. Year 3 repairs would address the conditions at Level 7 to allow it to be re-opened to the public. To provide a longer lasting solution than the continued patching of the topping slab, we recommend the complete removal of the topping slab and waterproofing system, and the placement of a bonded concrete overlay on the structural deck. While more costly upfront than patching and repairing the existing topping slab and waterproofing system, the bonded overlay will provide a long-term repair that will not require significant repair and maintenance for at least 20 years, and will save over $100,000 in the first 10 years with normal maintenance. The repair of Levels 5 and 6, as well as the façades, can be deferred until Year 4 since these levels, along with Level 1, have significantly less deterioration than the other levels of the garage. Painting of the entire garage is recommended after all levels of the garage have been repaired. Level 5 has the same waterproofing and topping slab system as Level 7 but has fared better because the topping may be thicker, it is better protected from rain and snow, and it is better protected from sunlight which drives vapor through the top of the slab promoting failure of the coating

19 The previously noted near term (Years 1 through 4) repairs, in general, require the following work items: 1. Repair of deteriorated and delaminated structural concrete. The waffle slab is only 4½ thick and will require full-depth repair between the joist stems, except for areas over the drop panels around the columns. 2. Replacement of deteriorated sections of the topping slab on Level Routing and sealing, and replacement of failed sealants, at cracks and construction joints. 4. Re-application of a waterproof traffic-bearing deck coating at Levels 1-4 and Replacement of the roofs over stair towers in Year Replacement of corroded drains and piping, and installation of additional drains at ponding areas. The suggested budget for near term repairs is approximately: Year 1: $1,195,000 Year 2: $1,630,000 Year 3: $ 880,000 Year 4: $ 865,000 Total: $4,570,000 Recommended longer term (6 to 10 years) maintenance and capital improvements include: 1. Ongoing concrete repairs at approximately 5 to 7 year intervals. Maintenance of waterproofing systems will reduce the rate of deterioration and future repair costs. 2. Ongoing replacement of deteriorated sections of the topping slab on Level Routing and sealing of cracks as they develop, and replacement of joint sealants as they fail. 4. Re-coating of the deck membrane system as it wears, estimated to be every 5 to 7 years at turning areas in the drive aisles, every 7 to 10 years in the straight drive aisles, and every 10 to 15 years over the parking stalls. The suggested budget for near term repairs is approximately: Year 7: $290,000 Year 10: $420,000 Total: $710,000 The determination of replacement costs for the parking structure requires additional study and information, but would likely be in the range of $8,000,000 to $12,000,000, depending upon whether the foundations can be re-used, if commercial retail space is desired at street level, and other improvements that may be desired

20 Recommended Upgrades to the structure include: 1. Modification or replacement of stair railings, such as the installation of a mesh or intermediate rails or balusters, at the two egress stairs. 2. Per your request, the cutting of openings through the stair tower walls to provide better visibility of the stairs is likely to be feasible. LIMITATIONS Deterioration of concrete, waterproofing, and other aspects of parking structures will occur due to exposure to water, chemicals, ultraviolet radiation and wear abrasion. Restoration and protection of the structure can be performed, and the rate of further deterioration reduced. However, we cannot guarantee that further deterioration will not take place with continued service-related exposure. Effective ongoing maintenance can significantly reduce long-term repair and maintenance costs. Monitoring of the facility can assist in scheduling future maintenance. Specific repair procedures are not part of this evaluation. This report defines items in need of repair and presents conceptual procedures. Construction documents are required to address all aspects of materials selection and methods for repair of the parking structure. The evaluation and restoration of existing buildings require that certain assumptions be made regarding existing conditions. Some of these assumptions may not be confirmed without expending additional sums of money and/or destroying otherwise adequate or serviceable portions of the building. Carl Walker cannot be held responsible for latent deficiencies, which may exist in the structure and have not been discovered within the scope of this evaluation. Carl Walker appreciates the opportunity to work with the City of Reno on the evaluation of the in Reno, Nevada. If you have any questions or require further clarification, please contact us so that we may discuss our findings and recommendations. We appreciate this opportunity to work with you and we look forward to hearing from you. Very truly yours, CARL WALKER, INC. William A. Mahler, A.I.A. Restoration Manager, Chicago Region Patrick D. Martin, P.E. Director of Restoration Enclosure: Capital Reserve Analysis Table