Report on Sanctuary/Chancel Crawl Space Inspection. St. John in The Wilderness, 2896 Old Lakeshore Road Bright s Grove. Project No.

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2 Report on Sanctuary/Chancel Crawl Space Inspection St. John in The Wilderness, 2896 Old Lakeshore Road Bright s Grove Project No. E Background St. John in the Wilderness (SJITW) is considering the viability of implementing an organ loft construction project at the rear of the Sanctuary. The intent is to have the organ permanently housed on a platform above the Sanctuary. Prior to embarking on this capital intensive project, SJITW decided to have the church structure appraised particularly the foundations and floor system in the Sanctuary which is the oldest part of the church. was retained to carry out an inspection and report on the findings. A prior inspection revealed that there was no access to any of the crawl space and so before a crawl space inspection could be carried out, a removable hatch had to be cut in the floor at the south west corner of the Sanctuary as shown on the attached plan forming Appendix A to this report. In addition, as it was suspected that there would be a full height foundation wall between the Sanctuary and the Chancel, a second hatch was cut in the block foundation wall on the north side of the Chancel. This work was carried out Wright Construction on November 6 th The under floor inspection was carried out by BKL on November 22 nd 2012 by a two man team with appropriate safety equipment for confined space entry procedures. The main criteria to be inspected were foundation cracks or settlement, damp in wood components, wet or dry rot, corrosion of any structural steel components any suspected mould or fungus. Although the conclusive detection of mould or fungal presence is outside the scope of this survey, any suspect areas would be noted and recommendations made to SJITW to conduct a hazardous building materials assessment by a qualified industrial hygienist.

3 2. Crawl space inspection findings 2.1 Chancel The first inspection was carried out through the new exterior hatch cut in the north foundation wall. This afforded inspection of the western half of the crawl space under the Chancel. Access to the east side was not possible due to the presence of the full height centre wall (see plan, Appendix A ). The floor consists of plywood decking on wood floor joists supported off the exterior concrete block foundation walls and an interior concrete block foundation wall. The walls were finished with a timber wall plate to which the floor joists were secured and then a perimeter timber rim board was nailed to the joist ends. The false floors are built up off that base floor. This structure of the raised floors could not be viewed from below. The floor joists were typically sistered where they overlapped on the centre wall bearing plate. The Chancel floor is higher than that of the Sanctuary Because of the reduced headroom, the uneven grade and the presence of heating ducts, it was not possible to physically progress through to the north foundation wall of the Sanctuary. However it was possible to view the structure mostly up to that point by flashlight. The sill plate on top of the block foundations and rim boards did show evidence of previous water damage but readings with the moisture meter registered moisture content less than 15%. Timber moisture contents less than 15% create conditions that are not conducive for mould or fungal growth. The floor joists and floor decking appeared to be in good condition and similarly registered moisture content readings less than 15%. When cutting the access opening in the north wall, some base flashings had to be removed. The plywood backing behind was found to be in a wet state with moisture contents registering well in excess of 15%. The Chancel crawl space grade did not have a polythene vapour barrier or sand covering, unlike that of the Sanctuary. The heating ducts were uninsulated galvanized sheet metal with only isolated areas of light corrosion. The overall atmosphere under the Chancel floor was characterized as being reasonably dry. The clearance height between grade and floor in the Chancel crawl space is slightly less than that found in the Sanctuary. Inspections of both the inside and outside of the exterior foundation walls did not show any signs of foundation settlement or movement. 2

4 2.2 Sanctuary The Sanctuary grade had a horizontal polythene sheet vapour barrier and a fairly level sand covering. The floor structure consisted of 2x10 timber joists at 12 o.c. supported off W8x18 steel beams spanning across the Sanctuary on to concrete blocks as foundation pads. The steel beams have a timber plate bolted to the top flange and the 2 x10 floor joists bear on top of that. The timber decking is tongue and groove timber plank decking laid diagonally on top of the timber joists. All of these components including the concrete foundations were in good condition. Because of insufficient headroom underneath the steel beams, it was not physically possible to progress beyond the line of the first beam from the south end wall. However inspection could be carried out beyond that with visually with a high powered flashlight. The steel beams have superficial rust over most of the surface but section loss is negligible. The floor joists, timber decking, headers and rim boards all appeared to be generally in good condition. There is a redundant crawl space gas furnace located in the south half of the Sanctuary sitting in a steel chequer plate box on the sand surface. The foundation walls appear to be poured in place concrete with window openings that have since been filled with concrete block. In some cases there are still gaps between the block and the header beam over the opening (see photos in Appendix A. The inside faces of the foundation walls in the Sanctuary area have fiberglass insulation batts attached in some areas but not all over. Some of the panels have since detached and the batts are lying on the subgrade. The foundation walls in the Chancel area do not have any insulation at all. Inspections of both the inside and outside of the exterior foundation walls did not show any signs of undue foundation settlement or movement inconsistent with the age of the building. Along the centre line of the Sanctuary there is a metal BX electrical cable that was either never fixed to the floor joists or had the cable clips detach and is lying on the sand subgrade. Although the sand is in a very dry state, there is significant corrosion on the metal jacket of the BX cable (see photos). The heating ducts are the same as in the Chancel crawl space, uninsulated galvanized sheet metal distribution ducting. There is little corrosion visible on the surfaces that could be seen. 3

5 4 3. Conclusions As discussed earlier, wood structures with moisture contents >15% are likely to to sustain organic decay processes. Wood structures with readings <15% are considered to be in a stable, rot free condition. The floor structures in the two crawl spaces inspected were found to be in a good condition with moisture contents <15% and the ground surfaces were considered dry. No moisture ingress could be seen inside the crawl spaces. Any areas of previous water ingress have stabilized and there is no active rot present. It is thought that the presence of the uninsulated heating ducts in both crawl spaces has helped to create a very dry environment and one hostile to the formation of fungal growth or wood decay processes. Similarly, the relatively dry crawl space conditions have limited the corrosion on the W8x18 steel beams to surface rust only. The steel beams and concrete foundation blocks on which they bear are all in satisfactory condition with no anomalies noted. In summary, the floor structures in both Chancel and Sanctuary that were inspected do not require any structural repairs at this time. We cannot comment on the floor structure of the east half of the Chancel crawl space as this could not be accessed as discussed in section 2.1. However, there is no reason to suspect that it would be any different from the west half which was inspected. There are some small gaps between the header beams around the exterior and the blocked in window wells and these have the potential to let in wind borne moisture and these should be sealed. Removal of the redundant gas furnace is not considered a necessity as it is disconnected from the supply and the expense of cutting up and replacing the floor to remove it cannot be justified. The most likely cause for concern is potential damage to the fabric of the building lies in the way water runs off the vinyl siding. Siding is most typically horizontal but in this case, the siding has been installed vertically. There is J channel at the bottom of the siding to finish off the cut edge and it is thought that this might be diverting water inside onto the bottom of the plywood sheathing, i..e on the inside of the siding. In view of the damage visible on the plywood sheathing where the north access hatch was made, it is recommended that the metal base flashing be removed around the perimeter of the Sanctuary and Chancel so that that the siding can be lifted and the plywood sheathing behind properly inspected.

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7 6 APPENDIX A PLAN OF ST. JOHN IN THE WILDERNESS

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9 7 APPENDIX B PHOTOS

10 8 Chancel crawl space exterior block wall Chancel crawl space looking south Sanctuary crawl space corroded BX cable Corroded BX cable close up

11 Sanctuary crawl space at ext. wall Sanctuary crawl space heating ducts 9 Sanctuary W8x18 beam bearing on foundation Sanctuary heating ducts Sanctuary crawl space redundant gas furnace -1 Sanctuary crawl space redundant gas furnace 2 Sanctuary crawl space W8x18 structural beams Crawl space under Secretary s office

12 10 Sanctuary crawl space block infill (note gap) Sanctuary crawl space block infill (note gap) Sheathing rot at bottom of siding, Chancel N. wall View of Chancel north wall - damaged sheathing New hatch Chancel north foundation wall Opening to crawl space under Secretary s office