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Rafe Hubbard
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1 July 22, 2011 via only: The Board of Directors of The Solace Condominium c/o Ms. Linda Schultz, Condominium Manager MCM Property Management Ltd th Avenue SW Calgary, Alberta T2P 1J2 Dear Board Members, Re: Parkade Leakage Investigation th Street SW, Calgary, Alberta Morrison Hershfield Limited (MH) was retained by Solace Condominium to a leakage investigation at the Solace Condominium (Solace), located at th Street SW, Calgary, Alberta. The investigation was authorized by Mr. Sheldon Thompson, Treasurer of the Board of Directors on behalf of Solace. The detailed scope of work, as outlined in our September 21, 2010 proposal, is as follows: Review available drawings and any previous reports with respect to the parkade. The purpose of the review is to determine the original design intent for the various related waterproofing assemblies and what reviews, testing and repairs have been completed to these components to date. Flood test the parkade foundation, beginning at grade and concluding at the base of the building exterior wall (or until the leak is identified). Each area may require a unique style of flood testing, depending on the nature of the building construction. Remove exterior overburden from the parkade podium slab to expose the slab/and or waterproofing membrane. Overburden items include, but not limited to, interlocking paving stones in the vicinity of the suspected infiltration points and retaining wall/fill. The overburden would be safely stored from pedestrians/vandals on the east end of the podium slab. MH would examine the membrane for signs of deterioration or lack of interfacing to adjoining envelope assemblies, and re-flood the suspected leakage area. Compile a report identifying the results of the review and providing recommendations accordingly, including estimated repair costs if applicable. Background: We understand that the Solace has experienced water penetration into the parkade area. On September 14, 2010, MH performed a cursory review of the parkade. During the review, active leakage was noted on the west elevation foundation wall between parking stalls 36 and 41. A similar active leak was also observed on the east elevation foundation wall at the parking stall 40.

2 - 2 - Documentation: MH was not provided with any documentation on the history of the parkade such as previous studies, nor were we provided with construction drawings or specifications. Our knowledge of the building envelope assemblies and subsequent recommendations are strictly based on exploratory openings and observations on site. Water Test Procedures: The following steps were taken to detect the leakage into the parkade: We examined the parkade for signs of leakage from the previous infiltration events to determine the areas to be tested. Excelsior Enterprises Ltd. (Excelsior), a landscaping contractor, was retained to assist MH with exploratory openings. Excelsior removed exterior overburden (unit paver stones, sand, etc.) from the parkade podium slab to expose the slab/and or waterproofing membrane at test areas. MH examined the condition of the existing waterproofing membrane at test openings and looked for signs of deterioration or lack of interfacing to adjoining envelope assemblies. Testing proceeded by spraying water on test openings (i.e. slab, foundation wall, and cladding). Water testing is designed to simulate actual storm events, thus, testing on each building component could require at least 45 minutes or more of water application for possible water penetration to be noticeable. Water testing is conducted by spraying building envelope elements from the base of the wall upward in order to control areas being wetted during different portions of the test (i.e. leakage path isolation technique). Finally, we observed and recorded points of water penetration, if any, which occurred during the test. Water testing, although somewhat reliable in identifying leakage locations, is not 100% accurate. The time required for leakage to occur may not be satisfied by the duration of the test, thereby leading to false results. Also, additional sources of leakage may exist that cannot be tested for during testing procedures due to saturation of previously found leakage paths. Observations: On July 8, 2011, Mr. Lawrence Zhang, P.Eng. of MH visually reviewed the site and performed water testing at test locations 1, 2, and 3 (discussed below). At each of the areas tested, the podium slab consisted of unit paver stones, approximately one inch thick sand/gravels, polyethylene slip sheet, and bituminous hot rubber membrane with approximately 3 to 4 inch upturns. The membrane appeared to be in fair condition with no signs of deterioration observed (Photograph 1). A typical podium slab waterproofing assembly consists of a protection board or drainage mat directly over the membrane to protect it from the sand/gravel bed above. Furthermore, a

3 - 3 - geotextile (filter fabric) is located below the sand bed, or is integrated into the drainage mat to prevent abrasion on the membrane. We not did undertake membrane cut tests for this exercise and therefore did not measure the thickness of the membrane, it adhesion to the concrete substrate, or determine the extent of reinforcing of the membrane (reinforcement is typically required between plies of liquid applied membrane by most waterproofing membrane manufacturers). Where reviewed; however, we did not note debonding membrane or deterioration as a result of a-typical installation. Photograph 1: Bituminous (hot rubber) waterproofing membrane observed on the horizontal surface of the podium slab Sign of water stains were observed on the west foundation wall between parking stalls 36 and 43; also at the east wall by parking stall 40. Concrete cracks were observed at the above mentioned locations. These water stains were noted under and north of the steps at the front entrance.

4 - 4 - Test #1: Location: Southwest corner of the north building (adjacent to the mailbox and above parking stall 43). Podium Slab Assembly: Unit paver stones; One inch thick sand/gravel bed; Polyethylene slip sheet; Liquid-applied hot rubber membrane; Concrete podium slab (as observed from inside the parkade). Spray testing began at 8:30 am on grade where the membrane was exposed. The area was flooded for 45 minutes, and no signs of water penetration were observed. Cracks in the parging north of the steps were observed. Water was sprayed onto the parging by the planter. After 15 minutes of applied water, penetration was observed on the west foundation wall at stall 43 through an existing crack (Photograph 2). Water testing was also conducted on the west entrance steps, as well as the parging to the south of the steps. Within 30 minutes of applied water, penetration was observed at the bottom of the foundation wall under the middle of the steps (Photograph 3) Photograph 2: Water penetration through existing wall crack stall 43

- 5 - Photograph 3: Water penetration at the bottom of the foundation wall below centre of steps Test #2: Location: Southeast corner of the parkade roof adjacent to the south steps.

5 - 5 - Photograph 3: Water penetration at the bottom of the foundation wall below centre of steps Test #2: Location: Southeast corner of the parkade roof adjacent to the south steps. Podium Slab Assembly: Unit paver stones; One inch thick sand/gravel bed; Polyethylene slip sheet; Liquid-applied hot rubber membrane; Concrete podium slab (as observed from inside the parkade). A stucco wall with metal flashing was installed above the parkade foundation wall, separating the Solace from the adjacent building. Signs of stucco repairs were observed at the bottom of the wall above the metal flashing. Water was sprayed onto the hot rubber membrane above the parkade roof as well as the upturns. No signs of leakage were observed after 30 minutes of the water test. Testing was heightened to include the metal flashing above the stucco. Immediately, water penetration was observed coming through the joint between the foundation wall and the concrete steps (Photograph 4).

- 6 - Photograph 4: Water penetration observed coming through the joint between foundation wall and concrete steps Test #3: Location: Approximately 6 meters north of the west steps (above parking

6 - 6 - Photograph 4: Water penetration observed coming through the joint between foundation wall and concrete steps Test #3: Location: Approximately 6 meters north of the west steps (above parking stall 36). Podium Slab Assembly: Unit paver stones; One inch thick sand/gravel bed; Polyethylene slip sheet; Liquid-applied hot rubber membrane; Concrete podium slab (as observed from inside the parkade). While the overburden removals were ongoing, ponding water was observed on the membrane as water drained onto the membrane from Test #1. During the initial site review, an existing crack was observed in the west foundation wall at parking stall 36. However, no water penetration was observed while water was applied directly above the podium slab at this location. Water was then applied into the planter at the west foundation wall. After approximately 30 minutes of spraying, water penetration was observed migrating through the crack at the above-mentioned location (Photograph 5).

- 7 - Photograph 5: Water penetration through the foundation wall at parking stall 36 Discussion and Recommendation: Based on the results of the water testing, there appears to be several locations

7 - 7 - Photograph 5: Water penetration through the foundation wall at parking stall 36 Discussion and Recommendation: Based on the results of the water testing, there appears to be several locations of moisture penetration into the parkade. At all three locations, water applied directly to the surface of the podium slab did not result in leakage. When applied to the vertical plane of the wall (below the podium in Test #1 and #3; above in Test #2) moisture ingress was noted. We believe that the cracking in the foundation wall has been accepting moisture in heavy periods of rain, causing leakage into the parkade. The same conclusion can be related to Test#2; however, with the leakage originating from above the metal flashing, thus above the slab, there is potential that the stucco wall assembly was improperly installed. As a result, the transition joint between the concrete steps and the below-slab foundation wall is susceptible to moisture infiltration when saturated by wind-driven rain. Without chipping back the parging on the west foundation, it is not known if a waterproofing membrane has been installed on the exterior of the foundation wall. We do not suspect that there is moisture protection due to the termination of the membrane at approximately 3 to 4 inches above the slab, however. With respect to a repair strategy, we recommend one of the following two options: Crack injection or exterior foundation wall membrane. With crack injection (Option 1), a contractor would rout out and clean the cracks from the interior. A polyurethane grout could then be

8 - 8 - injected into the crack, filling it with an impervious, flexible material. The intention of the injection of polyurethane would be to block all incoming moisture while moving with any further cracking. Crack injection has a history of performing well provided that the foundation does not continue to crack. This solution is expected to work 50% of the time but is the less-expensive of the two options. Estimation of this work is approximately $200 per linear foot plus contractor mobilization and demobilization costs. This preliminary opinion of probable costs should be used only as an order of magnitude budget at this time. Option 2 would involve excavating the soil against the foundation wall, removing parging and/or planters and installing a waterproofing membrane. As we only identified areas of leakage at visible cracks on the foundation wall, we would recommend only excavating and waterproofing to approximately 12 inches beyond the cracks in all directions. The work would likely extend vertically from the top of the wall to the footing. This solution typically performs longer than Option 1 but involves a much higher cost due to the amount of soil removal and reinstallation required to access the exterior of the foundation wall. With respect to Test #2, there appears to be issues with the wall-flashing detail above the slab. The exact nature of the problem is unknown, but water penetration appears to be occurring between the stucco and the flashing intersection. This could be due to poorly installed and/or reverse moisture barrier lapping, disjointed/negatively sloped flashings, lack of seals, or a combination of these. In order to address the leakage at Test #2, we recommend removing of the lower stucco along the side of the above-slab wall to review and possibly replace the flashing at this level. Moisture protection elements can then be properly installed and interfaced. Further investigation is required. As a general note, the podium slab waterproofing assembly was not originally constructed to best-building practices. Due to a lack of drainage mat or protection board, and filter fabric, there is a greater chance or premature membrane failure. We recommend reducing the service life of the waterproofing assembly in your next reserve fund study (budgeting for full replacement sooner).

- 9 - Closing MH can assist with the repairs of this area by contacting contractors with experience in either of the above noted recommendations and requesting pricing.

9 - 9 - Closing MH can assist with the repairs of this area by contacting contractors with experience in either of the above noted recommendations and requesting pricing. Generating a scope of work with a mini-specification would be required by MH prior to involving contractors. Follow-up with quality control site review would be recommended to ensure the scope is being properly undertaken. Should the Board wish to receive a proposal for these services, please contact the undersigned. We have enjoyed working with Solace on this assignment and look forward to a continued working relationship. Yours truly, Morrison Hershfield Limited Lawrence Zhang, P.Eng. Field Representative Building Science Division Jordan Bowie, C.Tech. Associate, Project Manager Building Science Division N:\PROJ\ THE SOLACE CONDOMINIUM - LEAKAGE INVESTIGATION\LZ- WATER TEST REPORT JULY 8, 2011 FINAL.DOC

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