Construction update: all about fly forms at minto775

In our last update, we mentioned a new type of equipment we were working to assemble on site that would see the formwork process through to the roof slab. So what better to focus on this month than fly forms?

Fly forms are a type of formwork that expedites the forming process when the structure progresses above grade and the floor layouts (at least for the structural components) become more regular and repetitive. For residential developments like minto775 King West, this typically happens by the 4th floor slab.

Large trusses are assembled between columns and walls and covered with plywood where the concrete is poured. Once the plywood is in place, the process is similar to that for forming below grade – bottom reinforcing steel is placed, electrical conduit, sleeving for mechanical lines and any in-slab duct is placed, followed by the top layer of steel and, finally, concrete.

Once a slab is poured and the concrete is strong enough, the entire truss section is flown out with the crane and landed on top of the new slab. Temporary jacks are put in place to support the slab as it continues to strengthen.

Connecting the fly form for hoisting to the next level

Fly form connected and ready for hoisting

hoisting the fly form out from under the poured slab

Fly form being landed for the next concrete slab

Once a complete level of sections of fly forms are built, you can see how efficient the process becomes. Aside from small infill sections spanning adjacent panels, the forms, once landed, are ready to go. To speed things up even more, where layouts for mechanical and electrical provisions repeat level to level (such as at the east tower), these markings on the forms mean that this aspect of the job for the mechanical and electrical trades doesn’t need to be repeated.

As far as progress on site, we are currently working on the 5th floor structure, with walls and columns to 6th underway. As the structure continues to extend above ground floor, architectural features such as the courtyard really begin to take shape.

View of the slab prior to the concrete pour

The mechanical in-slab duct is in place and the top reinforcing is being installed.

As mentioned in the last update, over the next few weeks the exterior work at the ground floor level will get underway, kicked off by the exterior studwork which will form the backing for the exterior brickwork. Window installation will begin in the last few days of March at the towers on floors 2 and above. Once a few levels of windows have been installed, interior studwork will begin to define the layouts of the suites. Until that time, the team is continuing to install the main mechanical and electrical provisions, both at the parking levels and above grade.