Setting Aluminum Forms for Concrete Walls and Foundation

Project: Storm-Ready Design, Episode 2, Part 1

Bob recaps construction of the stem-wall foundation and integral concrete slab, the vertical steel reinforcing, steel mesh, window bucks, headers, and spacers put in place for the cast-in-place concrete walls. Cameron Parker and the crew of Solid Wall Systems spray the aluminum wall forms with an organic oil spray to prevent adhesion from the concrete and set the forms for the pour. Bob joins Wayne Sallade, Charlotte County Emergency Manager, to review cleanup, demolition, and repair one year after Hurricane Charley. sallade explains that housing built in the 1960s through the 1980s, before the Florida Unified Building Code, had stick framing, gable roofs, and siding. "It didn't stand a chance," he says. Looking at surviving 1920s Florida architecture, it's clear that unified construction, concrete walls, protected windows, and hip roofsare the way to design wind-resistant homes. Back on site, bob watches the pour, learns how the walls and window openings will be vibrated to eliminate voids, and sees the bracing set to hold the walls square before leaving the site to let it cure overnight. Once the forms are removed, Jesse Gonzalez explains how a traditional three-coat Florida plaster job will complete the exterior once the structure has cured for two weeks.
Part 1: Setting Aluminum Forms for Concrete Walls and Foundation
Cameron Parker, production manager for Solid Wall Systems, shows Bob how the aluminum forms are prepped and erected for the concrete pour at the Punta Gorda, Florida, storm-ready house. Parker explains that the setting of forms takes a six-person crew about five hours. The forms are first sprayed with a biodegradable form oil so that the concrete will not stick to them and will be easily removed once the concrete has begun to set. The forms are locked with a wedge and pin system, with wall ties installed to hold the forms together and clips to hold the forms to the slab. Parker shows Bob how the specialized window bucks are used to create the window openings without use of lumber or additional material seams that could lead to leaking and water intrusion later on. After seven days of steady rain, the crew is ready to pour the concrete for the foundation and slab at the Punta Gorda, Florida, storm-ready home. Bob explains how code now dictates that foundations be elevated and supported by a three-course block stem wall set on reinforced footings below the grade. These perimeter stem walls are reinforced with horizontal and vertical number five diameter steel rods or rebar. The stem walls and slab are poured as one to create a seamless slab and foundation. This integral foundation will protect against water intrusion and hydrostatic pressure that lifts slabs and compromises structures when storm surge comes. The concrete is floated and polished to finish the slab before the reinforcing steel rods and mesh are set for the walls. Vertical steel rods are spliced to the reinforcing rods protruding from the foundation, then steel mesh is attached with wire to the rods. Stirrups and rebar create the headers, and spacers are attached to the mesh to keep it centered in the new wall once the concrete is poured.
Part 2: House Failures in Hurricanes
Part 3: Building a Reinforced, Solid-Pour Concrete Wall
Part 4: Removing the Concrete Wall Forms and Planning the Plaster Finish