French doors to close off a den in my Ottawa house?

Adding French doors to close off a den is a carpentry job that turns on one key question: whether the opening already exists at the right size, or whether framing needs to change to fit the doors.

If the opening is already there and the doors fit within it, the City of Ottawa's exempt list includes "Replacing doors or windows (provided they are in the same size opening)". If the opening needs to be widened, raised or cut new, that falls under "enlarging or relocating a door," which the City lists as permit work; confirm with Building Code Services before framing changes.

The door size matters for another reason. The Ontario Building Code (2024, O. Reg. 163/24) sets minimum doorway widths for rooms in a dwelling unit. Under 9.5.5.1., a doorway within a dwelling unit is designed to accommodate at least the door size in Table 9.5.5.1.; for rooms the table does not list separately, such as a den, that is 760 mm by 1 980 mm. Ask the carpenter how the pair of doors meets that size. Ask the carpenter to confirm the rough opening and finished clear width before ordering doors.

A few things shape what the work involves and what a quote should cover:

• Whether the wall is load-bearing. If it is, any new or widened opening needs a lintel designed to carry the load to adjacent studs; a qualified, registered designer (BCIN), an engineer, or you for a house you own, handles that sizing.
• The door style: prehung pairs in a single frame versus doors hung separately in a built-up frame affect both materials and labour.
• Whether the existing floor, ceiling and wall finishes need patching after the frame goes in.
• Hardware: hinges, a centre astragal, handles and any latch or lock set.
• Disposal of any material removed.

Ask the carpenter to specify the door species or material, the frame depth relative to your wall thickness, and whether the floor threshold needs any work at the bottom of the opening. Get the scope in writing: what framing is included, what patching is included, and what the warranty covers on the installation.

Before work starts, make sure you have a signed written contract that spells out the full scope and price, any permit if the opening is changing, and any design drawings if a lintel is involved.