Towering over the skyline in Philadelphia, the new Comcast building is in the final stages of completion. One of the biggest tenants in the building is the Four Seasons Hotel taking over the upper ten floors of the building from the 48th floor up to the 60th floor. The building, designed by Lord Norman Foster and Partners, New York City and built by one of the most distinguished General Contractors in Philadelphia, L.F. Driscoll, rises up sixty stories over the city. The building is topped out with a beautiful Spa and work out facility on the 57th floor and a high-end restaurant with amazing vistas of the City on the 59th and 60th floor.

With a building of this size and with the high standards expected, there are always challenges faced by Driscoll to provide the best quality for the owner. For this reason, Driscoll hired Surface Specialist to help engineer the floor slabs for the high end flooring finishes to be installed on the floors comprising the Four Seasons Hotel. "Certainly, with a building of this size and scope, there will always be some movement in the concrete slabs through deflection and settling" said Tim Fahey, Owner of Surface Specialist.

The challenge for Surface Specialist was three fold: 1. To load the building with tons of small bags of underlayment up to the floors starting on 48 and going up to 56: 2. To use their special mixing equipment up on each floor to eliminate the dust when mixing the product, a result of the new OSHA regulations on airborne silica dust and, 3. To use a product that could finish out extremely flat and hard.

Since Surface Specialist came onto the project after the outside hoists were removed, they had to rely on the interior elevators to load the building with upwards of 200 skids of underlayment. They had to fit into a very busy schedule of other trades loading building materials into the building.

The mixing of the bags of engineered cement was accomplished by using a large enclosed mixing chamber called a "Hippo" that had a HEPA vacuum attached to it creating negative air flow when the bags of underlayment were opened and poured though a small opening. This new mixing system reduced the amount of airborne silica dust to acceptable levels.

Surface Specialist used a proprietary performance underlayment called L3 by Platform Performance Cements, a subsidiary of Dependable Floor Products. Andy Bailey, Project Manager for Surface Specialist commented that this product has exceptional flow characteristics enabling the product to become very flat to meet the strict 1/8" in 10' specification tolerances. The 28 day compressive strength exceeds 5000psi and hardens quickly enough to allow light trades traffic after 12 hours.

The project is continuing to move forward and L.F. Driscoll is very impressed with the quality and efficiency of the Surface Specialist team.