What holds the ceiling up while a bearing wall comes out in Barrhaven?

The ceiling stays up during a wall removal because the loads that wall carries have to go somewhere before any cutting starts. Temporary supports carry the floor or roof above while the wall is out, and they stay in place until the permanent beam and its posts are installed and bearing.

The temporary support has to line up with the framing above it, not just sit under the drywall. Where the loads land, and where the temporary supports go, depends on the span of the opening, what is above the wall and how the joists run. That is a question for whoever designs the beam, not something to work out on site without a plan.

What the carpenter is actually doing, in order

The job follows a fixed sequence. A qualified, registered designer (BCIN), an engineer or an architect, or you for a house you own, sizes the beam and posts first. The permit comes next. Then the temporary support goes in. The bearing wall comes out, the beam goes up, the posts carry the load down, and the inspector signs off before patching starts. Skipping or reordering any of those steps puts the structure at risk while the wall is open.

The posts matter as much as the beam. The load the beam picks up has to travel down through posts, then through the floor framing, and eventually to the foundation. Your designer traces that load path and tells you whether anything below needs reinforcing before the wall comes out.

A few framing minimums from the 2024 Ontario Building Code are worth knowing when you review the plan: each end of the beam needs at least 89 mm of bearing; where a lintel spans an opening in a framed wall, the studs on each side are doubled for a lintel up to 3 m long and tripled beyond that (9.23.10.6.); and a wood post must be at least 140 mm by 140 mm unless calculations show less is adequate.

Comparing two written quotes? Check that each one names the same scope of work, spells out who designs the beam and who applies for the permit, lists the materials by type, and covers patching and clean-up as a paid line rather than an afterthought.