Flat Roof Membrane Repair

Address:
475 Patricia Avenue
Toronto, Canada
This Toronto private school building changed ownership in the past year and underwent an extreme makeover. The roof was leaking in multiple locations and this meant that the 30,000 square foot roof needed a roofing membrane upgrade. By leaving in place existing dry materials along with upgraded insulation and an upgraded roofing membrane, we successfully repaired this roof on time, and under budget.
The Ask
The client in question (a Toronto area private school) was looking for a 20 year workmanship warranty, and required a roofing membrane upgrade in order to qualify for said requirements. The replacement would have to be done while classes were in session. Safety was imperative during this project, as the primary school children had recess close to our working area at the footprint of the building.

Our Approach
Our team worked closely with the engineer of record (Pretium Engineering) on this project. The damaged insulation was replaced and a new layer of 2.0″ ISO coated glass facer + 0.5″ Perlite was installed over the existing insulation/gypsum board assembly at the recovery area. The balance of the roof, over the concrete substrate areas, was replaced in the usual manner with a new vapour barrier, 2 layers of 2.0″ ISO coated glass facer + 0.5″ Perlite coverboard. The membrane was the same on all roof areas. We were also able to save some of the dry insulation and re-use it on two of the roof areas, eliminating waste and offering our client some savings. There was also less debris to remove that might have resulted in dust getting inside the premises.
Special Considerations
Because of the proximity to children, our team requested that protective hoarding be installed around the footprint of the building to provide a safety barrier. A hybrid membrane was used in order to reduce the amount of asphalt bitumen used, which in turn reduced any concern for odour or fumes during school hours.
Outside of safety concerns, the roof itself housed 19 rooftop HVAC systems with gas piping running throughout requiring daily coordination with the school’s HVAC contractor. Our team worked closely with the engineer of record in order to ensure a safe repair without interfering with piping below the deck substrate.
While we take pride in all of our projects, the work we did on this roof is one that we are particularly proud of. We were able to complete the project without incident, all without closing down either the school or the playground for the students and qualify our client for a 20-year OIC (original installed cost) workmanship warranty from Johns Manville. With multiple roofing concerns, we had to use every tool in our box to complete this project, and we are delighted to report that not only were we successful, but this project was also featured by the manufacturer in 2021 National Roofing Week.
Specifications
Type of Project: Full Replacement/Recovery
Roof area: 30,505 sqft.
Deck Type: Steel & concrete
Roof Membrane (field area): 3 ply hybrid – 1 ply SBS sand-sand base sheet + 2 plies type 4 glass felt, flood coat of asphalt and pea gravel
Flashing Membrane (perimeter and roof upturns): 2 ply SBS modified bitumen
Insulation:
- 10,465 sft recovery area at steel deck substrate – over top of existing 0.5 fibreboard insulation, 2.5″ ISO insulation and 0.5″ gypsum board – we added 1 layer of 2.0″ coated glass facer ISO insulation and 0.5″ perlite insulation
- 20,040 sft replacement area at concrete substrate – 2 layers of 2.0″ coated glass facer ISO insulation and 0.5″ perlite insulation
Contact Elite Roofing for your next roofing project!
If your roof needs repairs or a replacement, but you don’t want to shut down operations, contact us. There are always options for roofing work that does not have to affect the day-to-day functionality of your structure. That’s the Elite Advantage.