CSDA Contractor Uses Precision Techniques to Convert Downtown Chicago Landmark
Since 1971, 820 South Michigan Avenue was a Chicago address which evoked status. Overlooking Lake Michigan in the Monroe Harbor district, the building had been built as the headquarters of the groundbreaking African-American publications Ebony and Jet, and was designated a city landmark in 2018.
By 2019, the building had outlived its usefulness as office space, and had been vacant for the past seven years. It was scheduled for a $20 million conversion into 150 rental apartments. But conversion of this 13-story, 48-year-old landmark sandwiched between neighboring buildings, including a hotel, posed significant safety and demolition challenges.
The architectural plans for 820 South Michigan Avenue called for premium views of Lake Michigan on the north side of the building. Unfortunately, there were no windows on the north wall, which meant the wall would have to be removed. The plans also called for adding a top floor and a light well.
United Insulated Structures Company of Berkeley, IL was selected as the general contractor (GC) and hired Midwest Wrecking Company of West Dundee, IL for the demolition portion of this project. It was determined that the precision offered by concrete cutting and demolition would be the best way to remove and modify the existing structure while avoiding damage to the adjacent buildings. CSDA member Hard Rock Concrete Cutters (HRCC) of Wheeling, IL was contracted by Midwest Wrecking Company, with whom they had a long-standing relationship, to handle the concrete cutting and selective demolition aspects of the job. HRCC spent two months planning the details and safety expectations of the job, as there were many factors complicating the demolition. Midwest Wrecking owner and GM Glenn Lampa said, “Our decision to use Hard Rock was based on their focus of project safety, history of finding solutions on difficult projects and the professional sawing technicians they provided. Safety was paramount on this project.”
The standard approach of breaking up and discarding the 18-inch concrete beam and columns was rejected, as it would have required too much protection for the adjoining buildings, added risk and extra time. There was also insufficient capacity in the 1970’s era elevators to remove that much debris. Hard Rock determined that the safest and most efficient method would be to cut the north wall into sections and remove them by crane. The pieces would be lowered to street level for disposal. The crane would stand in the only space available – an adjoining empty lot on the south side of the building, opposite the actual work.
The north wall measured 105 feet tall, 16 feet wide and 10 inches thick. This concrete wall only existed on the top floor. The remainder of the brick wall was removed by Midwest Wrecking. HRCC systematically cut the concrete wall (including 18-inch concrete beams and columns) into 28 panels weighing 7,500 pounds each. Each 3.75 ton panel was rigged and hoisted over the top of the building by the crane and safely delivered to street level. When all the panels were removed, openings 80 feet long and 12.5 feet high could be seen across the north face of the building.
HRCC then cut 11 floor openings with Husqvarna and Diamond Products slab saws, with each opening measuring 80 feet by 12 feet 6 inches by 4 inches on a 20-inch concrete pan joist floor. Then, they core drilled 704 4-inch lifting holes into the concrete slabs and lifted 176 pieces of concrete weighing 7,000 pounds each. The openings were shored to the bottom of the joist and pulled with the crane.
Naturally, safety was a heightened concern as large openings mean open edges. Workers near these leading edges wore harnesses, scaffolding outlooks were built on each floor to allow access for blade maintenance and precautions were taken to safely secure saws while working near the leading edge. The existing structure also had to be shored in place to safely cradle cut concrete until each piece was rigged and removed by crane. Safety consultants, Hard Rock’s safety management team and the project’s safety professionals spoke regularly during the scope of the project and conducted pre-job safety meetings. HRCC employees underwent daily Job Safety Analysis and Silica site surveys to identify daily exposures and to ensure proper performance.
Despite the challenges, HRCC finished the saw cutting and removal days ahead of schedule. An eight-week timeframe had been allotted, which HRCC completed 10 days ahead of schedule. The GC and Midwest Wrecking were thrilled with the results and HRCC was awarded additional work on the project for the MEP contractors.
HRCC VP and Project Manager Kevin Coakley said, “This was a high-profile job on the Magnificent Mile of South Michigan Avenue in downtown Chicago. I am proud of the upfront planning and teamwork we displayed by working with other trades to make sure the job was done safely and ahead of schedule. This was a complete team effort from our safety manager to our superintendent, to our field operators and helpers who made this job go as planned. This will be one of the buildings I point out to my kids and annoy them with the “Let me tell you what Hard Rock did at this building!”
Tools and equipment used on the 820 South Michigan Avenue project included: • Husqvarna FS6600 D Slab Saw • Diamond Products Core Cut Deep Saw • ICS/Pentruder High Cycle Wall Saw • Hilti Core Drills • Protech and DDM Concut blades and core bits In all, HRCC cut over 63,000 feet of concrete and cored over 700 holes. The company was chosen for this job because of their reputation, professionalism and relationship with Midwest Wrecking Company. CSDA contractors have time and time again proved that they posses all of these qualities that GCs are looking for in hiring a concrete cutting and demolition contractor. The 820 South Michigan Avenue building is now ready for tenants, thanks to the excellent job done by Hard Rock Concrete Cutters.
A CSDA member since 1989, Hard Rock Concrete Cutters, Inc., has been in business for 28 years. The company is based in Wheeling, Illinois, and services the entire Chicagoland area. Hard Rock Concrete Cutters employs 58 employees, has 28 trucks and offers the concrete cutting services of slab sawing, core drilling, wall sawing, hand sawing, wire sawing, grinding, concrete polishing, staining and GPR imaging. The company is a CSDA Certified Company and employs CSDA Certified
United Insulated Structures Company Berkeley, IL
Midwest Wrecking Company Chicago, IL
Concrete Cutting Contractor
Hard Rock Concrete Cutters Wheeling, IL
Methods Used: Slab Sawing, Core Drilling, Wall Sawing