Reference: BRM A0 July 18 th, Cursory Visual Review of Various Below Grade Spaces and Exposed Foundation Walls

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1 Reference: BRM A0 July 18 th, 2014 Toronto Catholic District School Board 80 Sheppard Avenue East Toronto, Ontario M2N 6E8 Re: 1.0 Introduction Exp Services Inc. (exp) was retained by the Toronto Catholic District School Board (TCDSB) to visually review existing conditions of three (3) below grade class/storage rooms and corresponding exterior exposed foundation walls including interior and exterior spaces of the main entrance at St. Patrick Catholic Secondary School, Toronto, Ontario following reports of active leakage at basement level. 1.1 Background The subject building is an institutional school-type building structure located at 49 Felstead Avenue, Toronto, Ontario that was reportedly constructed circa According to TCDSB, the rooms, 102, 104 and 105 on the below grade level are exhibiting signs of moisture penetration and dark staining. It was reported that some rooms have had a history of some flooding from leak(s). Exp Services Inc. (Exp) was on-site on July 7 th, 2014, to visually review the existing conditions of three (3) below grade class/storage rooms and other spaces and corresponding exterior exposed foundation walls including interior and exterior spaces of the main entrance (facing Felstead Avenue). During our site review it was also observed that the metal stairs adjacent to the main entrance appeared to be exhibiting surface corrosion Clark Boulevard, Brampton, ON L6T 4V1, Canada T: F:

2 1.2 Scope of Work Exp carried-out a cursory visual interior review of the conditions of rooms 102, 104, 105 and main entrance spaces, and exterior conditions of exposed foundation walls, grading, and other related building appurtenances on the north side, to provide restoration recommendations. Structural analysis, environmental reporting, a review of the design and/or physical testing was not part of the scope of work. No architectural drawings were made available for our review, however we did review some basic floor plan layout drawings to help with our orientation. 2.0 Visual Review Our site visit consisted of a random review of visible interior and exterior surfaces corresponding to interior spaces exhibiting evidence of moisture penetration at the north and eastern exterior elevations to provide remedial recommendations to mitigate further moisture ingress. During our site visit, it was observed that ceiling tiles at various locations had been removed prior to our site visit which allowed exp to view conditions above the drop ceiling of the below grade spaces reviewed. The following observations were found at the time of our site visit: 2.1 Observations.1 Room 102 Upon review, it was noted that the suspended ceiling tiles, near the northern concrete foundation wall, appeared to have moisture staining and ceiling tile deterioration (cracking of surface material). Visual review of the ceiling spaces above the drop ceiling showed that the support beams encased in plaster wall assemblies (bulk head) at the soffit expansion joint of the floor slab above appeared to be corroded. Significant damage to the plaster wall bulk head surrounding the expansion joint beams was also evident including damage to the plaster wall metal reinforcement. Exp noted that localized wall surfaces, of the northern concrete wall, had areas of paint coating deterioration which appeared to be consistent with moisture damage (refer to Photographs 1, 2 and 3). In addition, exp noted areas of paint peeling and staining on the foundation concrete wall, which appeared to be consistent with moisture penetration (refer to Photograph 4). The condition of the surface corrosion at the expansion joint beams, moisture damage to the plaster wall bulk head, and wall staining observed appeared to be consistent with significant expansion joint and foundation wall water penetration damage. 2

3 Photograph No. 1 Photograph No. 2.2 Room 104 and 105 Photograph No. 3 Photograph No. 4 It was noted that both rooms felt damp and humid with limited ventilation. It was observed that the northern and eastern concrete foundation walls appeared to show moderate staining and paint coating deterioration consistent with moisture damage. Review of spaces above the drop ceiling showed mild deterioration/corrosion of the plaster wall bulk head assemblies in the form of plaster coating delamination, rust coloured staining and corrosion of the plaster metal reinforcing assemblies in room 105, which appeared to be moisture related. Some areas of mild staining were also observed, which appeared to be moisture related (refer to Photographs 5, 6 and 7). 3

4 The deterioration of interior celling finishes and staining of the foundation walls observed appeared to be consistent with moderate foundation wall water penetration damage, humid environment possibly due to limited air ventilation. Theatrical materials were being stored in room 105 which were reported to have been previously propped against the wall but which were subsequently moved away from wall surfaces. We observed moisture staining on some theatrical materials (refer to photograph 8). Photograph No. 5 Photograph No. 6 Photograph No. 7 Photograph No. 8 4

5 .3 Eastern Hallway, Below Grade Floor Upon review, it was noted that localized areas of the drop ceiling had paint coating deterioration which appeared to be consistent with moisture damage. The condition of the paint coating deterioration observed is considered to be mild although in general, the existing ceiling surface appeared to be in serviceable condition at this time (refer to photographs 9 and 10). Photograph No. 9 Photograph No Eastern Exterior Elevation Visual review of the underside of the overpass above the exterior stairs appeared to show signs of concrete deterioration, rust coloured staining, exposed/corroded metal reinforcement. A significant amount of staining was observed on the exterior wall underneath the overpass. Exp observed a significant crack at the underside of the ribbed precast concrete cladding. Localized areas of the ribbed precast cladding appeared to extend below finished grade and gaps were found between the precast panel and the abutting asphalt pavement. A section of self-adhesive waterproofing membrane (commonly known as Blue-skin ) applied to the foundation wall appeared to punctured and debonded. Exp noted algae growth on various exterior concrete surfaces throughout reviewed building elevations more specifically near ground levels (refer to Photographs 11, 12, 13 and 14). 5

6 Photograph No. 11 Photograph No. 12 Photograph No. 13 Photograph No Northeast Exterior Elevation Exp noted algae growth on various exterior concrete surfaces throughout reviewed building elevations more specifically near ground levels and at the service door landing, along the retaining concrete wall by the access ramp. We also observed localized areas of deterioration (cracking of surface material) at the base of the ribbed concrete wall, near the access ramp and on the concrete parapet wall. Visual review of the grated service well showed signs of moisture staining, cracking, displacement and distorted along with significant accumulation of detritus within the well (refer to Photographs 15, 16, 17 and 18). 6

7 Photograph No. 15 Photograph No. 16 Photograph No. 17 Photograph No Main Entrance Upon review of the main entrance, it was observed that sealant material at the base of the precast concrete wall appeared to be de-bonded and deteriorated. Vertical areas of deterioration (cracking of surface material) were noted on the left of the main entrance doors. It is recommended that vertical areas of deterioration be repaired to prevent moisture ingress into the building (refer to Photographs 21 and 22). It was also that the ceiling had paint coating deterioration which appeared to be consistent with moisture damage and the ceiling tiles within the main entrance near the staircase, appeared to show signs of moisture staining. Localized areas of the floor tiles within the main entrance, appeared to be cracked. condition appeared to be moisture related (refer to photographs 21, 22 and 23). This 7

8 Photograph No. 19 Photograph No. 20. Photograph No. 21 Photograph No. 22 8

9 Photograph No. 23 9

10 3.0 Conclusions and Recommendations Based on our review of various below grade class/storage rooms and other spaces and corresponding exterior exposed foundation walls including interior and exterior spaces of the main entrance it appears that moderate to significant water penetration has occurred through the existing foundation wall and other exterior cladding components. Consequently, we are of the opinion that the foundation walls and cladding corresponding to areas of visible moisture damage require remediation which requires further testing (for example test pits) and investigation to determine the composition and condition of the existing waterproofing system to mitigate any further water penetration. In order to mitigate further water penetration at the reviewed foundation walls and basement spaces, we recommend the following maintenance repairs as well as capital renewal remediation. 3.1 Maintenance Repairs In order to affect a long term repair strategy, a significant amount of effort and time would be required to implement the capital renewal remediation plan in addition to proper investigation and design. Therefore, we propose the following immediate maintenance type repairs until such time as the formal capital renewal remediation work can be implemented in the short term: Minimize occupancy and control access to these areas; Properly remove deteriorated wall paint to prevent dust build-up and clean visible surface staining and continue with proper regular periodic maintenance cleanings; Properly remove/replace damaged and stained ceiling tiles; Replace deteriorated and de-bonded sealant materials at the interface of the entrance landing and the base of the precast concrete wall; Remove detritus from within the service concrete well and properly seal wall penetrations at redundant mechanical units; Operate a commercial grade dehumidifier in these rooms, properly sized to help reduce air moisture. Maintain stored material clearances from the foundation walls (say at least 0.5m), store materials susceptible to water damage on raised pallets, possibly removing these items and any stained items as well as dispose of items which are no longer required to minimize storage volume. The probable cost for these maintenance repairs is estimated to be approximately $10,000 plus HST. Some work will be covered as part of ongoing routine maintenance activities. 10

11 3.2 Investigation and Design In the short term, in order to affect a long term repair strategy, the following is recommended for the short term: Carry-out test pits to determine the composition and condition of the existing waterproofing system; Review existing mechanical systems for possible improvements and/or design new system to adequately ventilate interior air and remove excess air humidity; Review the condition of the existing expansion joint and framing to provide rehabilitation recommendations; Review the condition of corroded metal support beams and related structural elements; and, Prepare formal rehabilitation specifications and design drawings. The probable cost for the investigation and design activities is estimated to be $20,000 plus HST. 3.3 Capital Renewal Remediation Based on the investigation and design phase, implement the formal rehabilitation plan to mitigate any further water penetration. 11

12 4.0 Limitations Client: Toronto Catholic District School Board The information presented in this letter report provides our assessment based on observations made at the time of our site visit, within the terms of reference and limitations outlined in this report. We have been asked to make recommendations and opinions based solely on a visual sampling. Test cuts, coring, environmental testing, design review, destructive testing, or instrument testing were not carried out. Consequently, further detailed investigation or additional testing may change our current recommendations and opinions. In order to achieve the objectives outlined herein we arrived at conclusions based upon the best information presently known to us. No investigative method can completely eliminate the possibility of obtaining partially imprecise or incomplete information; it can only reduce the possibility to an acceptable level. Professional judgment was exercised in gathering and analyzing the information obtained and in the formulation of the conclusions. Like all professional persons rendering advice, we do not act as absolute insurers of the conclusions we reach, but we commit ourselves to care and competence in reaching those conclusions. We trust that this report is satisfactory for your purposes. Should you have any questions, please contact this office. Sincerely, exp Services Inc. Jaime Rodriguez, B.Tech. (Arch.Sc.), C.E.T, RRO Senior Project Manager Building Assessment Group Mauro Caschera, P.Eng. Senior Project Manager Building Assessment Group 12