9.25.2.1. Required Insulation (1) All walls, ceilings and floors separating heated space from unheated space, the exterior air or the exterior soil shall be provided with sufficient thermal insulation to prevent moisture condensation on their room side during the winter and to ensure comfortable conditions for the occupants. (2) Insulation shall be provided between heated and unheated spaces and between heated spaces and the exterior, and around the perimeter of concrete slabs-on-ground. (3) Reflective surfaces of insulating materials shall not be considered in calculating the thermal resistance of building assemblies. (4) Except as permitted in Sentences (5), (6), (7), (8), (13) and (14) the minimum thermal resistance of insulation shall conform to Table 9.25.2.1. Table 9.25.2.1. Minimum Thermal Resistance of Insulation to be Installed based on Degree Day Zones(1) Forming Part of Sentence 9.25.2.1.(4)  Building Element Exposed to the   Exterior or to Unheated Space

RSI Value Required


 

Zone 1   Less than 5000

Zone 2   5000 or more

Electric   Space Heating   Zone 1 & 2


Ceiling below attic or roof space

5.40

6.70

7.00


Roof assembly without attic or roof space

3.52

3.52

3.87


Wall other than foundation wall

3.00

3.87

4.70


Foundation walls enclosing heated space

1.41

2.11

3.25


Floor, other than slab-on-ground

4.40

4.40

4.40


Slab-on ground containing pipes or heating ducts

1.76

1.76

1.76


Slab-on-ground not containing pipes or heating ducts

1.41

1.41

1.41


Column 1

2

3

4 Note to Table 9.25.2.1.: (1)Number of degree days for individual locations are contained in Table 2.5.1.1. (5) Except for doors on enclosed unheated vestibules and cold cellars, and except for glazed portions of doors, all doors separating heated space from unheated space shall have a thermal resistance of not less than RSI 0.7 where a storm door is not provided. (6) All sliding glass doors separating heated space from unheated space shall have a thermal resistance of not less than 0.30 m2°C/W. (7) All glazing that separates heated space from unheated space shall have a thermal resistance of not less than 0.30 m2°C/W. (8) The thermal resistance values in Table 9.25.2.1. for exposed roofs or ceilings may be reduced near eaves to the extent made necessary by the roof slope and required ventilation clearances, except that the thermal resistance of insulation at the location directly above the inner surface of the exterior wall shall be at least RSI 2.1. (9) Where an enclosed unheated space is separated from a heated space by glazing, the unheated enclosure may be considered to provide a thermal resistance of 0.16 m2°C/W. (10) When electric space heating is used in a category TIL3 dwelling unit, all sliding glass doors separating heated space from unheated space or the outdoors shall have an energy rating of not less than -13 ER. (11) When electric space heating is used in a category TIL3 dwelling unit, all glazing that separates heated space from unheated space or the outdoors shall have an energy rating of not less than -13 ER for openable windows and 0 ER for fixed glazing. (12) The energy rating required in Sentences (10) and (11) shall be determined in conformance with CAN/CSA-A440.2-M, “Energy Performance Evaluation of Windows and Sliding Glass Doors”. (13) Except as provided in Sentences (14) and (15), log wall construction and post, beam and plank construction shall have a minimum thermal resistance of RSI 2.1 for the total assembly. (14) The thermal resistance value in Sentence (13) for the total wall assembly may be reduced to not less than RSI 1.61 if (a) the thermal resistance of insulation for the exposed roof or ceiling required in Table 9.25.2.1. is increased by an amount equivalent to the reduction permitted in this Sentence, and (b) for log walls, the logs have tongue-and-groove or splined joints. (15) Where milled log walls are installed, the thermal resistance value in Sentence (13) for the total wall assembly does not apply if (a) the mean thickness of each log is not less than 150 mm, (b) the thermal resistance of insulation for the exposed roof or ceiling required in Table 9.25.2.1. is increased by RSI 0.53, and (c) the logs have tongue-and-groove or splined joints.