Project: 73,000 square foot shopping centre sunk up to 6”.
Installer: Lève-Béton PURLIFT
Challenge: The shopping mall was built in 2010 on a concrete structural 8” thick slab. A number of factors had contributed to the slabs having sunk, including one or more of the following:
The mall is occupied by big box stores and the unevenness of the slabs created trip hazards in the stores as well as other challenges, such as keeping the shopping carts from careening in different directions due to the sloping of the floor.
The builder could have removed and replaced the existing slabs, thus leading to major revenue losses and storage costs for the retailers, not to mention the cost of leasehold improvements once the floor was replaced.
Findings: The builder contacted Purlift to look at the possibility of lifting, levelling, and stabilizing the floor in each store. Purlift sent a team of experts in that field in order to determine if/how the floors could be repaired with a minimal amount of business interruption. Purlift found that the problem could be resolved by injecting high-density 4lb. polyurethane foam beneath the slab. The slab would be pierced every 5’-7’ and the material would be injected in a liquid state, infiltrating crevices as small as 1/32”, thus filling the void and lifting the slab to its original position.
Results: Purlift started the work in November and worked through the busy Christmas season, accomplishing the feat by working at night so the stores could stay open throughout the day. The crew would start the job once the store closed for the night and left the site in the early morning so as not to disrupt the everyday working of the retail outlets. As a result, the retailer did not sacrifice 1 day of revenue and the work, done without any heavy machinery or equipment, was completely non-intrusive with no down time. Lifting the floor with all the racking, shelving, inventory, and storage equipment in place was not a problem as the polyurethane foam had no problem lifting the excess load sitting on the slab.
Installing Contractor: Purlift
Products Installed: High-density 4lb. polyurethane foam