EPS Waffle Forms for Cast-In-Place Structural Slabs

The Project
A concrete contractor was awarded a contract to repair all of the floors in a multi-story parking garage in Brooklyn, NY that was originally constructed using fiberglass waffle forms. In some areas they needed to replace entire sections of floor and in other areas just replace the slab but the structural concrete and rebar grid pattern would remain intact.

The Problem
If they used fiberglass forms to do the repairs, due to the rigidity of fiberglass, they would not get a tight fit between the forms and the existing concrete grid that was left intact. A second issue was that the fiberglass forms were constructed with bases and if everything did not line up perfectly concrete could seep between the forms resulting in a project that would not have a clean finish. Also the fiberglass waffle forms can be expensive.

The Solution
Since the contractor had worked with Universal Foam Products in the past they approached us to help resolve the problems. Universal designed waffle form liners using .9 lb density expanded polystyrene in two different styles. One style was designed with a bottom flange for when entire sections of floor were being replaced. The other style was designed without the flange to be used in the areas where just the slab had been removed and the grid remained in place.
Since the .9 lb EPS has some flexibility, the forms fit snuggly between the existing grid leaving a very clean finish on the concrete after they were removed. The forms were coated on the top and sides by the contractor with Ureshell Hard Shell Foam Coating, which is a two-part polyurethane coating, so the form liners would be used multiple times. A 1” diameter hole was drilled in the center of the form so compressed air could be used to release the form from the concrete.

Additional Benefits of EPS Waffle Forms by Universal Foam Products
EPS Waffle Forms are produced economically in any size and in small or large quantities. They can be coated at the factory or in the field to reduce costs. The Ureshell Hard Shell Foam Coating or other hard surface coatings can be used. The forms ship from multiple locations throughout the country, reducing freight costs.