STRUCTURAL BUILDING CONDITION SURVEY

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1 STRUCTURAL BUILDING CONDITION SURVEY Our Project No Prepared For: Mayfair Hotel Development Corporation Date: 3 December 2014; Revised: 15 December 2014

2 15 December 2014 Mayfair Hotel Development Corporation c/o 260 King Street West Suite 200 Kitchener, ON Attention: Bernie Nimer Re: 11 Young Street/ King Street West, The Mayfair Structural Building Condition Survey Our Project Dear Bernie: As requested, we have completed our structural condition survey of the above noted property. Our findings and methodology are summarized in detail in the attached report. In general the structure was found to be in poor condition. Regardless of your plans for this property, any activities in the building whether construction, renovation or demolition should be performed with extreme care as several areas of framing have a potential for collapse if subjected to potentially even minor loads. We appreciate the opportunity to be of service to you. Please do not hesitate to contact us if you have any questions relating to the contents of this report. Yours truly, Cory Zurell, PhD, P.Eng. Blackwell blackwell.ca Page 2 of 24

3 TABLE OF CONTENTS Introduction 4 Methodology 4 Description of Structure 4 Summary of Observations 11 Young Street 5 Summary of Observations 156/158 King Street West 18 Conclusions and Recommendations 22 blackwell.ca Page 3 of 24

4 STRUCTURAL BUILDING CONDITION SURVEY Our Project No Initial Review Date: 23 October 2014 Follow up Review Date: 15 December INTRODUCTION 1.1. Blackwell was retained by Mayfair Hotel Development Corporation to undertake a structural condition survey of the former Mayfair Hotel located at 11 Young Street/ King Street West in downtown Kitchener The purpose of our survey is to determine viability for the potential redevelopment of the property This report describes the methodology of the review, gives a general description of the building s structural systems and lists our observations and recommendations. 2. METHODOLOGY 2.1. Our scope of work included the following: Visual Condition Survey Visit the site to perform a thorough visual condition survey of the existing structure Document our findings with qualitative recommendations for remedial work, if required Address the potential for redevelopment of the property, including the addition of storeys to the building, for mixed use occupancy and including a hotel component Prepare a report summarising our findings and recommendations We understand that structural drawings of the building do not exist Based on our initial visual findings, we did not perform any analysis of the existing structural members Our initial review of the 6 storey portion of the building fronting Young Street (11 Young Street) was performed on 23 October Our subsequent review of the 3 storey portion ( King Street West) was performed on 15 December blackwell.ca Page 4 of 24

5 3. DESCRIPTION OF STRUCTURE 3.1. General The existing structure consists of the original 3 storey block (ca. 1905) with a partial 3 storey vertical addition that was built ca The structural system consists of load bearing brick masonry walls with floors consisting of light frame wood joists and beams, with steel columns and steel beams on the upper floors The floors are largely open space with no partitions. 4. SUMMARY OF OBSERVATIONS 11 Young Street 4.1. Exterior The exterior brickwork from the 2 nd floor up is in reasonably good condition. Some minor cracking is visible. blackwell.ca Page 5 of 24

6 The brickwork, ground to second floor, on the Young St. elevation and on a portion of the King Street elevation is not entirely original. Some areas are in poor condition, including at the sidewalk level A portion of the brick masonry wall along the Young St. elevation is supported at the second floor with a built up timber beam. The timber is currently exposed to the elements, however it appears that it was formerly covered and protected from moisture Long term exposure to the elements may cause future damage to the supported brick as the timber shrinks and swells with varying moisture content. Prolonged exposure may lead to decay of the timber. blackwell.ca Page 6 of 24

7 There are several steel columns supporting the timber beam noted above on the Young St. elevation. The columns are inset into masonry and terminate below grade on the foundation wall. Corrosion is apparent and layers of rust can be flaked off of the columns indicating loss of section Portions of the Young St. brick masonry wall appear to be slightly bowing out toward the street. It was not possible to confirm or quantify any amount. blackwell.ca Page 7 of 24

8 4.2. Basement/Ground Floor Framing Bridging between joists is missing in various locations The joists sag noticeably, likely due to long term creep effects At the King Street end of the basement, there is a section of floor that is comprised of what appears to be a concrete beam/slab. There is no apparent support for this infill area, apart from friction with the adjacent framing This area should be shored prior to allowing workers to walk above The built up wood beams down the centre of the building show significant sag, likely due to long term creep wood under the load of the concrete/terrazzo floor finishes above. Some plies appear to have failed. The beams also exhibit ineffective load sharing between the inner plies and outer ledgers. blackwell.ca Page 8 of 24

9 Framing at the back of the building, near the existing stair, is structurally deficient and some members have failed. blackwell.ca Page 9 of 24

10 Mold is present on the wood framing in the area of the stairs If not already addressed, prior to significant further activity in the building, we advise that the mold be tested to determine risks to workers. blackwell.ca Page 10 of 24

11 4.3. Ground Floor/Second Floor Framing A small section of masonry wall on the Young St. side, adjacent to a large drain pipe, is bulging inward and has been temporarily shored A large area of floor framing near the stair is structurally deficient. The header supporting the floor joists is heavily notched at one end and the trimmers on each side appear to have failed Access to the area of 2 nd floor above this framing should be restricted until it can be shored, repaired or demolished. blackwell.ca Page 11 of 24

12 Evidence of a fire is apparent in the framing near the entrance on the Young St. side of the building. Several burnt and charred joists were sistered with new framing; the sister joists do not span fully to the support and the nailing of the splice is structurally inadequate Access to the area of 2 nd floor above this framing should be restricted until it can be shored, properly repaired or demolished. blackwell.ca Page 12 of 24

13 Two spans of the built up beams supporting the 2 nd floor toward the back of the building have failed all four main plies of the beam are broken Due to lack of lighting, the beams toward the King St. end of the building could not be properly assessed Access to the area of 2 nd floor above this framing should be restricted until it can be shored, properly repaired or demolished. blackwell.ca Page 13 of 24

14 4.4. Second Floor/Third Floor Framing Much of the 3 rd floor framing is concealed by ceiling boards, preventing review of much of the framing There are various areas of localized framing deficiencies notched joists, cut members, missing headers, etc Third Floor/Fourth Floor Framing The fourth floor framing appears to include framing members that comprised the ceiling of the original building roof. The original members are covered with ceiling, preventing review of much of the framing There are various areas of localized framing deficiencies notched joists, cut members, missing headers, etc. blackwell.ca Page 14 of 24

15 Steel beams (appear not to be original) frame east to west. The brick masonry wall on the Young St. side has pulled away from the beams in several locations. Total movement appears to be in the order of 50mm to 100mm. A cause of this movement was not apparent Fourth Floor/Fifth Floor Framing There are various areas of localized framing deficiencies notched joists, cut members, missing headers, etc. blackwell.ca Page 15 of 24

16 4.7. Fifth Floor/Sixth Floor Framing There are various areas of localized framing deficiencies notched joists, cut members, missing headers, etc Sixth Floor/Roof Framing The roof rafters span east west to a central 3 ply 2 x7½ built up beam The built up beam is of inadequate size for the spans and expected loads. Further the member is spliced at improper locations This built up beam has failed in several locations. The ceiling framing is providing supplemental support in several locations. In others, the ceiling framing has failed as well. blackwell.ca Page 16 of 24

17 As winter is approaching, access to the sixth floor should be restricted completely once snow accumulates on the roof. blackwell.ca Page 17 of 24

18 5. SUMMARY OF OBSERVATIONS 156/158 King Street West 5.1. Exterior The King St. facade includes a large steel lintel which is currently unprotected and exposed to the elements The end of a built up wood beam supporting the second floor framing extends through the facade and is unprotected and exposed to the elements. blackwell.ca Page 18 of 24

19 Steel columns supporting the large steel beam lintel are encased in masonry which is degraded in places. The columns are rusted and sustained moisture is evident in wicking on the surface of the steel at the base The masonry above the second floor is in fair to good condition. It appears to have been previously painted Basement/Ground Floor Framing The ground floor framing is largely covered by finishes and could not be reviewed in detail. No signs of distress were noted Ground Floor/Second Floor Framing The second floor is comprised of 2 x14 ± wood joists supported by masonry walls and a central line of columns and beams There is charring in various locations, indicating past building fires. Several of the charred original joists toward the back of the building were sistered with 2x10 s, presumably following the fire event. blackwell.ca Page 19 of 24

20 Two spans of the original built up wood beams down the centre of the building have been supplemented with additional, newer, built up beams below Second Floor/Third Floor Framing The third floor framing is concealed by ceiling and was not visible for review. It is assumed throughout to be of similar construction as the second floor framing There is a noticeable sag in some areas that is likely due to long term creep of the wood framing. blackwell.ca Page 20 of 24

21 5.5. Third Floor/Roof Framing The roof is comprised of wood deck supported by open web steel joists, steel beams and columns. The framing is not original to the ca.1905 building Not all joints in the roof decking occur at supporting joists however it is not T&G wood decking. Joints that occur in planks between supports have resulted in occasional broken planks. Care should be taken if work is carried out on the roof to ensure localized areas are not overloaded; workers need to be careful where they step. blackwell.ca Page 21 of 24

22 Leaks in the roofing are evident in two locations. 6. CONCLUSIONS AND RECOMMENDATIONS 6.1. Concerning the condition of the existing building structure: Compared to similar buildings of this construction type (masonry wall with timber framing), the existing structure has significant areas of structural deficiencies and failed members Access to the building should be strictly limited and various areas noted should be restricted completely until the framing is made safe through shoring, repair or demolition Should you have the need for any future work to be carried out by contractors within the building, we recommend you provide us the opportunity to meet with them prior to their accessing the site to discuss issues related to life safety Concerning Redevelopment of the property: In general there are three realistic scenarios related to redevelopment of this property: Retention, repair and upgrade of the existing structure Retention of the existing King Street and Young Street façades for incorporation into a new building structure Complete demolition of the existing building in favour of new construction Scenario 1: Retention, repair and upgrade of the existing structure There is little structural value in the existing building structure, particularly the six storey portion at 11 Young Street Large areas of failed and deficient framing would have to be completely rebuilt The remaining framing in some areas is unlikely to have sufficient strength for current code specified occupancy loads The structure, including the foundations, would not likely be structurally adequate to support additional loads necessary to reach a reasonably level of serviceability with respect to fire protection and sound transmission. blackwell.ca Page 22 of 24

23 A full upgrade to the lateral load resisting system to meet current code requirements would be necessary Should there be any desire to vertically expand the existing building, the existing structure does not have sufficient capacity without extensive upgrades, including to the foundations Given the current state of the existing structure overall, little, if any, framing is salvageable in the 11 Young Street portion with respect to renovation Based on our experience, it is likely the extent of work required to remediate this building up to an acceptable condition would be significantly more costly than new construction, especially given the constraints of working within the existing building A qualified cost consultant or experienced general contractor should be consulted if an order of magnitude cost is desired. Should this option be pursued, higher than average contingencies for structural work are recommended Scenario 2: Retention of the existing façade for incorporation into a new building structure Given the appealing brickwork of, particularly, the second and third floors, we assume this could be a desired pursuit Given the poor aesthetic and inconsistent quality of the masonry from ground to second, we would anticipate that this option would likely require shoring of the existing façade from the second floor up, and subsequently supporting the façade by a new structure Construction process necessary to support the existing masonry in such a scenario would impart a significant, and perhaps prohibitive, premium to the cost of a new building. We are unable to estimate the order of magnitude such a premium would represent and recommend that, should this be the direction you wish to pursue, a contractor well experienced in such work be consulted On this particular site, demolition of the existing structure would be greatly complicated by retention of the façade. The limited site access indicates a premium cost should be anticipated. blackwell.ca Page 23 of 24

24 Scenario 3: Demolition of the existing building in favour of a new building Due to the proximity of streets and adjacent buildings, a reputable demolition contractor experienced in such constrained sites would be essential in successfully executing the demolition Any significant excavation for a basement(s) would likely require shoring in order to approach the property lines to maximise the footprint Should a new structure exceed the height of the existing grey stone clad building to the east, snow drifting onto the lower roof would have to be considered and either the adjacent roof reinforced, or a snow shelf provided to mitigate overloading Given the condition of the existing structure, and the potential cost involved in the retention of all or of part of the existing building, this scenario is likely the most cost effective of the three considered. A qualified cost consultant or experienced general contractor should be consulted if an order of magnitude cost is desired. blackwell.ca Page 24 of 24