How is selective structural demolition planned in an occupied building?

Removing a load-bearing wall, cutting a floor opening or taking out a column changes how loads travel through the building. An engineer designs the new support, specifies the temporary shoring and sets out the sequence. In Markham, structural changes need a building permit, and the drawings form part of it. Without a design there is nothing to plan against.

Shoring is installed to the engineer's specification and checked before any structure is disturbed. The sequence matters: in many cases the new beam or header is installed first, then the old structure is removed beneath it. Nothing should be cut until the temporary support is confirmed.

• Shoring posts and beams set to the design
• Loads transferred before cutting
• Cuts planned so pieces are controlled as they come free
• Shoring left until the permanent structure is accepted

Structural elements often carry services. Before cutting, electrical circuits, plumbing, gas lines, sprinkler piping and ductwork running through the area are identified and isolated by the appropriate trades. In a building that stays open, isolation has to be planned so the rest of the building keeps power, water and fire protection.

Occupants need a clear boundary. That can be hoarding, sealed poly walls with zipper doors, or a closed floor. Exits must stay available and signed, and fire alarm and sprinkler impairments are arranged through the building owner with fire watch where required.

Cutting concrete and masonry creates silica dust, which must be controlled with water, vacuum-equipped tools and containment. Noise and vibration are scheduled for times agreed with the building, within Markham's construction hours. Sensitive neighbours, such as clinics or labs, may need advance notice of vibration.

Older buildings hide things: undocumented beams, previous repairs, abandoned services or materials not listed in the survey. The plan should say who is called when something unexpected appears and that work stops until it is resolved. The Designated Substance Survey under OHSA section 30 should be in hand before any work, and suspect materials not in it are tested before they are disturbed.

People working or living in the building need to know what is happening and when. A short notice before work begins, naming the area affected, the working hours, the loudest days and who to contact with a concern, goes a long way. Updates when the schedule changes keep trust. For offices and clinics, a single contact at the building, usually the property manager, relays information to tenants so the crew is not fielding questions mid-cut. After each phase, walk the boundary with the building contact to confirm exits, signage and protection are still in place.

We plan selective structural work from the engineer's drawings, install and check shoring before cutting, and coordinate isolation so the rest of the building stays live. Work areas are sealed and scheduled around the occupants. See our structural demolition and interior demolition pages, or request a free estimate.