The engineer has found a way to remove the wall. Then the large grille near the floor enters the conversation.
A room can become more open and less comfortable at the same time if the air route is treated as somebody else's detail.
Find out what the wall contains
Before finalizing the opening, identify ducts, pipes, wiring, and any concealed return-air cavity. A grille's position is useful evidence, but it does not reveal the full route or establish that the existing arrangement is suitable to reuse.
Have an HVAC professional assess the proposed layout. Natural Resources Canada's duct-design guide treats return-air installation as a design decision. Air needs a workable route back to the equipment as well as a route into the room.
Put the structural and mechanical drawings together
A flush beam can occupy space that a duct previously crossed. A new post can occupy a former chase. Ask the designers to resolve those intersections before the final framing is ordered.
Possible layouts may retain a short wall section, use an alternative chase, or accept a small bulkhead. Have the HVAC design establish the required route and sizing. Moving the same grille somewhere convenient is not, by itself, an airflow check.
Decide which compromise you can live with
Imagine a fully open wall with a conspicuous ceiling box, versus a wide cased opening that contains the service route at one side. The second option may feel more deliberate, even though the opening is smaller.
That is a room-design comparison worth seeing in elevation. It is hard to judge from a floor plan full of thin lines.
- Show the grille location and accessible duct route.
- Check conflicts with the beam, posts, cabinetry, and lighting.
- Include the rerouting and making good in the quote.
- Agree how the altered system will be checked when complete.
Keep the inspection sequence visible
Toronto's inspection guidance lists HVAC rough-in separately. Confirm the applicable inspections and leave the work visible until they are complete.
The finished opening should look intentional and the rooms should still be comfortable. Both outcomes deserve space on the drawing.