Total Roof Area: ~64,000 sq. ft. (two buildings)
Material Manufacturer: Johns Manville (JM)
Existing Membrane Removed: 4-ply BUR with gravel
New Insulation: R-50 — 8½″ polyiso (in 3 layers) + ½″ perlite cover board
New Membrane: Mod-bit: asphalt-applied base sheet + torch-welded white granular cap sheet (JM)
Skylights Replaced: 28 total: 16 (front) + 12 (rear) — low “e” argon glass units
Vented Skylights: 3 openable units in rear building
Skylight Curb Slope: 5% minimum for water runoff
HVAC Curbs: All raised with curb extensions and duct extensions (subtrade)
Plumbing Vents: All adjusted to required height above new roof (subtrade)
Roof Drains: New drain connections at all locations (both buildings)
Knee Wall Detail: Metal upstand, insulation and new flashing detail (front building)
Copings: 26-gauge black pre-painted sheet metal (both buildings)
The front building comprised two roof levels: a lower office roof and a main (upper) roof. Both levels featured a configuration like the rear building, with the following distinctions:
A high-performance R-50 insulation system was installed across both buildings, consisting of:
This represented a substantial increase in thermal insulation depth over the existing assemblies (4 inches on the rear building; 2½ inches on the front building), necessitating coordinated modifications to all existing roof penetrations and curbs.
A modified bitumen (mod-bit) system was installed above the new insulation assembly, with materials supplied by Johns Manville:
All existing acrylic double-dome skylights on both buildings (28 units total) were removed and replaced with new glass skylight units. To accommodate the glass glazing and ensure adequate drainage, sloped curbs were fabricated and installed at a minimum 5% slope for proper water runoff.
Due to the client’s concern regarding heat buildup caused by machinery within the rear building, three of the 12 replacement skylights were specified as openable, vented units. This allows for manual heat relief as required during operations.
The significant increase in insulation thickness rendered the existing HVAC equipment curbs too low relative to the new roof surface. To address this:
All plumbing vent stacks required upward adjustment to maintain required clearances above the new roof surface. A licensed plumber was retained, with the client’s approval, to complete all vent stack height modifications on both buildings.
The increased insulation depth rendered the existing drainpipe extensions too short to properly interface with the roof drains. New drain connections were made at all roof drains on both buildings to ensure full watertight integration with the new assembly.
All skylight curbs were raised to accommodate the increased insulation thickness. New sloped wood curbs were fabricated at a 5% slope to ensure proper water shedding from the curb framing surfaces, as required for the glass skylight units.
A specific challenge arose at the vertical knee wall separating the lower office roof from the main upper roof on the front building. The following scope was completed to ensure a watertight transition:
The project was successfully completed in May 2026. The new R-50 assembly substantially improves the thermal envelope of both buildings. The coordinated engagement of subtrades—including HVAC and plumbing contractors—allowed all curb and penetration transitions to be addressed comprehensively within the scope of the roofing project.
The installation of three vented skylights in the rear building provides the client with a practical solution for heat management. The full replacement of all 28 skylights with glass units enhances both daylighting quality and long-term durability compared to the original acrylic domes.
While the actual energy savings have not yet been realized fully, the client says the extra insulation reduces electricity demand at night time. In fact, according to Henry Silberman of Bennett Tools,
“On hot days we used to run the AC 24 hours a day; now we can chill the building at night when the electricity cost is low and we don’t have to cool as much during the day.”
In addition, the client noted that as the weather gets hot and more machines are added to the building, another AC unit will not be required, lowering capital costs further.
The roofing system at Bennett Tools was only one part of the equation. The significant increase in insulation thickness required careful coordination of HVAC curbs, ductwork, plumbing vent stacks, roof drains, skylights, and wall transitions to ensure every component remained fully functional and code-compliant. Elite Roofing worked closely with specialized subtrades to manage these complex details and complete the project seamlessly without interfering with building operations. By taking a comprehensive approach rather than focusing solely on the membrane installation, Elite Roofing provided Bennett Tools with a high-performance R-50 roofing system, improved energy efficiency, enhanced daylighting, and long-term protection.
That’s the Elite Advantage!
