OBC 2006 › Division B

12.3.4.2.

Version 0 — in force 31 December 2006

In force

Verified · covered Verified against the 2006-12-31–2007-04-01 consolidation, whose range covers the query date. How to read this

In force

Verified · covered Verified against the 2006-12-31–2007-04-01 consolidation, whose range covers the query date. How to read this

Provenance

New in this edition — no OBC 1997 predecessor

Base · O. Reg. 350/06 · ext← current

Original — base regulation

Content moved to SB-10, not yet covered

12.3.4.2. — Thermal Resistance of the Building Envelope

(1) Except as permitted in Sentences (2) and (3), the minimum thermal resistance of all walls, ceilings and floors that separate heated space from unheated space, the exterior air or the exterior soil shall conform to Table 12.3.4.2.A.

(2) Where the top of a foundation wall is less than 1 200 mm above the adjoining ground level, those portions of the foundation wall that are above ground may be insulated to the level required for the below grade portion of the foundation wall.

(3) The minimum thermal resistance of a slab-on-ground shall conform to Table 12.3.4.2.B.

(4) The maximum overall coefficient of heat transfer for windows that separate heated space from unheated space shall conform to Table 12.3.4.2.C.

(5) Except for swinging glass doors, the minimum thermal resistance of doors that separate heated space from unheated space shall be not less than RSI 0.7.

Editor's note

As filed in O. Reg. 350/06, the caption of Table 12.3.4.2.A. ends 'Based on Degree-Day Zones(1)' with the footnote marker '(1)' set inline and tight against the preceding word; the current e-Laws consolidation sets the marker as a superscript, raised rather than inline, with no amending regulation making the change. The footnote reference is the same, and this map preserves the caption as filed.

Text · e-Laws consolidated snapshot

Table 12.3.4.2.A. Minimum Thermal Resistance of Building Assemblies Based on Degree-Day Zones(1) Forming Part of Sentence 12.3.4.2.(1)


Column 1	Column 2	Column 3
Building Assembly	Minimum RSI Value of Assembly⁽²⁾
	Zone 1	Zone 2
	Less than 5000	5000 or more
	degree-days	degree-days
Opaque wall assembly	2.63	3.83
Wall assembly adjacent to unconditioned space	1.61	2.02
Below grade wall⁽³⁾	2.11	2.82
Roof assembly	3.91	5.68
Floor assembly over unconditioned space	4.52	4.52

Notes to Table 12.3.4.2.A.:

⁽¹⁾ Number of degree-days for individual locations are contained in Supplementary Standard SB-1.

⁽²⁾ The thermal resistance determined for the building assembly shall take into account the thermal bridging in the assembly, as determined by Supplementary Standard SB-10.

⁽³⁾ “RSI value” shown is for insulation only.

Table 12.3.4.2.B. Minimum Thermal Resistance for Slab-On-Ground Insulation Forming Part of Sentence 12.3.4.2.(3)

Column 1	Column 2	Column 3	Column 4
Type of Slab-On-Ground	Position of Insulation	Length of Insulation, mm	Minimum RSI Value Required⁽¹⁾
Unheated	Horizontal	600	3.17
	Horizontal	1200	1.94
	Vertical	600	1.41
	Vertical	1200	0.70
Heated	Horizontal	600	3.52
	Horizontal	1200	2.29
	Vertical	600	1.76
	Vertical	1200	1.06

Notes to Table 12.3.4.2.B.:

⁽¹⁾ “RSI value” shown is for insulation only.

Table 12.3.4.2.C. Maximum Overall Coefficient of Heat Transfer for Windows Forming Part of Sentence 12.3.4.2.(4)

Column 1	Column 2
Window-to-Wall Ratio	Maximum Overall Coefficient of Heat Transfer Required, W/ m²·°C
less than 0.2	3.01
0.2 to 0.4	2.28
more than 0.4	1.70