Setting Precast Footings

A new home on Cape Cod was slated to have a 1,100-square-foot covered porch that measured 78 feet along one side and wrapped around one corner of the house. Plans called for the porch and its roof framing system to be supported by 16 perimeter footings and an additional four footings to support the wider porch section at the end of the house. Because the roof was to be a prefabricated truss system that was ordered about the same time as the footing installation, there was little margin for error or for misalignment of the footings. In addition, the project was located in one of Cape Cod’s high-wind zones, so the alignment of all the support and framing components was a critical structural detail specified by the engineer to resist the uplift potential of the large porch roof. In this article, architect, high performance home guru, and frequent JLC contributor Steve Baczek and builder Jim Wolffer explain why precast concrete piers were the right choice for the project, and the steps that were taken to install them so that they would be perfectly aligned – within 1/8-in. both vertically and horizontally – when it came time to install the porch framing. Another cool detail is the perimeter ground-gutter system, designed to make sure the footings remain in position for the long term.