When our client approached us to design their dream home, one of the criteria was to build the structure like a commercial building. While having had worked on commercial structures before with steel framing, we had never used it throughout a house. Our client also wanted to use precast floor slabs. These would be installed quickly and allow the work to progress so the house could be enclosed. The broader goal was to have the building exterior finished so that exterior work would be minimal and their neighbours could enjoy their properties for the summer without fear of noise and dust issues. With the foundation complete, the next step was to erect the structural steel and precast floors which took a week and a half.
The first 3 images above show the construction for the pouring of the foundation. The racks contain a kit of parts that are combined to form higher foundation walls. Due to the deep basement, there are a lot of steel re-enforcing bars in these walls.
The foundation was poured and set, the factory-made pre-stressed concrete slabs were put in place. Re-enforcing bars will go into all the notches you see and into the ends of the slabs. Grout will be used to seal all the seams.
With the grout completed, then the steel columns for the second floor are installed. The last picture in this series shows you this progress.
There are a couple of things to consider when using this type of construction for your home. You pay a premium for these materials and the process. Given the cost escalation of wood framing products due to COVID this year, this premium is not as high as it might have been in ‘normal times.’
The pre-planning and coordination required for this type of construction are much more than wood framing, and we could not have executed this project without our 3D BIM software Archicad. The Structural Engineer, Steel Fabricator, and Precast Fabricator all relied on our architectural model for dimensions. Unlike wood, steel cannot be cut easily on-site to fit, therefore all work had to be accurately planned in the factory for assembly on site. Any changes in the shop drawing process were transferred into our model to keep it up to date.