McLean County Museum of History

Western Specialty Contractors Replaces Leaking Roof in Bloomington, IL
McLean County Museum of History, Helps Save Historic Relics

Extensive water damage from an aging roof threatened to destroy treasured artifacts housed at the McLean County Museum of History in Downtown Bloomington, IL. The water intrusion resulted from a 30-year-old, damaged roof that had exceeded its useful life span by more than five years, allowing rain to leak through the roof and insulation, clay tile, and mortar down into the building’s ceilings and interior rooms.

The nationally accredited, the award-winning museum occupies the former McLean County Courthouse, an American Renaissance-style structure built between 1900 and 1903. The building features a limestone-clad facade and solid masonry construction with a steeply sloping roof connecting the built-in gutter to the clocktower dome rising from its center. The old roof consisted of a 4-ply, built-up asphalt roof over one-inch perlite insulation mopped to the clay tile deck.

Although the McLean County maintenance staff had repaired the roof over the years, it no longer functioned properly and needed to be replaced immediately, along with the historic building’s drainage system. According to reports, as much as 14 gallons of water had leaked into the building after heavy spring rains, causing extensive damage. Although the water had damaged no artifacts, one area of the museum had to be closed off, and an office was relocated due to the leaking roof.

In 2020, the McLean County Board agreed to hire Scharnett Architects & Associates of Bloomington to perform architectural and engineering services to replace the building’s roof and improve its drainage system. Western Specialty Contractors’ Peoria Roofing Branch was contracted to replace the historic building’s damaged roof, with work on
the project was starting in May 2021.

Western’s crew removed the old roof and replaced it with a Firestone UltraPly TPO roofing system consisting of an 80 mil white membrane over gypsum coverboard, Polyisocyanurate insulation, and vapor barrier directly over the clay tile deck.

“The entire job was very challenging. We had to stage materials on the grounds as we needed them because the old clay tile deck could not be overloaded,” said Western Specialty Contractors Peoria Assistant Branch Manager Jared Osterman. “Tearing off the old roof every day was equally difficult because we had to crane materials down and up from the street as we progressed.”

The architect designed the new TPO roof system to go above and beyond what the manufacturer recommended, with double membrane thick valleys and ridges and built-in gutters lined with TPO and terminated with a liquid flashing, three-course step. The liquid flashing was use in place of counterflashing to minimize the use of mechanical fasteners in the historic structure. The job also required a 30-year, 80 MPH Firestone Roof warranty, including hail, cut, and puncture resistance.

Western’s Springfield, IL Branch also participated in the project by grinding out reglets, reworking the clay tiles around the drain replacements, and cleaning and sealing limestone at the gutter edge.

Performing a successful mock system pull test to ensure the new roof’s viability and strength, Western completed the roof replacement in September 2021. The museum had been closed to visitors during the roof replacement project while its restrooms were remodeled and its lighting fixtures replaced.

Julie Emig, the museum’s Executive Director, noted that the staff was relieved when the roof was restored. “The quality of Western Specialty Contractors’ work, especially given the complexity of this project, was outstanding. We no longer
worry that the next rainstorm could damage our award-winning collections and exhibits.”

Jim Maloof Realtor Peoria Office

Western Specialty Contractors – Peoria, IL branch was recently contracted by Jim Maloof Realty to install a new roof on its commercial office building, plus remove and box-in existing skylights with HVAC penetrations.

A portion of the building’s roof (16,700 sq. ft) was barrel-shaped and featured a modified roofing system that had been directly adhered to a wood deck. Due to the extent of the roof’s deterioration and leaking, Western’s crews recommended applying a new TPO mechanically fastened roof on top of the existing one, replacing the gutters, installing TPO wall flashing, and removing and infilling the old skylights with HVAC penetrations. A TPO fully-adhered roof was recommended for the building’s flat, concrete roof section (4,000 sq. ft).

Challenges faced by Western crews on the project included the removal and replacement of a large amount of rotten wood, removal of the skylights and working atop the barrel-shaped roof.

Western subcontracted with an HVAC company to unhook the rooftop units, as well as re-route the wiring and piping inside them after Western had removed and boxed-in the old skylights. Boxing in the abandoned skylight curb entailed mounting joist hangers on the wall of the curb and sheathing the area with plywood and flashing over the top with the roof membrane.

To keep workers safe on the steep roof, they wore harnesses and tied-off, and were encouraged to take their time while working. The project was completed within budget and took one month to finish. The end result was a beautiful, water-resistant roof that will protect the building from damage for many years to come.


Sisters of the Third Order

Western Specialty Contractors recently completed a roof replacement project at the Sisters of the Third Order of Saint Francis Motherhouse in East Peoria, IL.

The project scope of work called for the removal of the existing roof membrane and insulation. The roof deck was then inspected and replaced as needed. Two layers of one and a half-inch insulation board was applied with fast curing 100 adhesive. Next, a 0.60 mil TPO fully adhered membrane was installed along with new TPO coated metal at the roof perimeters.

The owners were furnished with a 20 year warranty.