The Ontario Building Code | Minimum Window Areas

9.7.2.3. Minimum window Areas

(1) Except as required in Article 9.9.10.1. and Sentence (3), the minimum window glass area for rooms in buildings ofresidential occupancy or rooms that are used for sleeping shall conform to Table 9.7.2.3.

Table 9.7.2.3.
glass Areas for Rooms of residential Occupancy

Forming Part of Sentence 9.7.2.3.(1)

Item	Column 1 Location	Column 2 Minimum Unobstructed glass Area With No Electric lighting="http://thehandyforce.com/electrical/" title ="East York Electrician">lighting	Column 3 Minimum Unobstructed glass Area With Electric lighting="http://thehandyforce.com/electrical/" title ="East York Electrician">lighting
1.	Laundry, basement recreation room, unfinished basement	4% of area served	windows not required
2.	water closet room	0.37 m²	windows not required
3.	Kitchen,	10% of area served	windows not required
	kitchen space,
	kitchen alcove
4.	Living rooms and dining rooms	10% of area served	10% of area served
5.	Bedrooms and other finished rooms not mentioned above	5% of area served(1)	5% of area served(1)

Notes to Table 9.7.2.3.:

⁽¹⁾ See Subsection 9.9.10.

(2) The unobstructed glass area of a door or skylight is considered equivalent to that of a window.

(3) Work areas in live/work units shall conform to Clause 3.7.2.1.(2)(a).

(4) Where rooms with different requirements for window glass area are combined as described in Sentence 9.5.1.4.(1), the more restrictive requirement shall govern.

9.7.3. Performance of windows, Doors and Skylights