2006 OBC Code Change Overview

February 28, 2007

New Code – Objective Based Format

New Layout – 2 Volumes

Volume 1 – 3 Divisions

Division A – Compliance, Objectives and Functional Statements, and Definitions

Division B – Basically current code as it exists now with approximately 700 technical changes

Division C – Administrative Provisions

Volume 2

Attribution Tables
Supplementary Standards (previously Supplementary Guidelines)

Still to be released - Application and Intent statements
 

Highlights of Division B – Part 9 Housing Changes
 
• Section 9.3 Concrete

New cement standard

Concrete for interior floors increased from 15 to 20 MPa

Code no longer references “slump” for concrete, uses water to cementing materials ratio

• Section 9.4 Structural Requirements

Composite snow loads now calculated by formula. No longer found in Table 1.2 in SB-1 (previously Table 2.5.1.1).

OBC now permits the use of CWC design handbook as alternative to tables in 9.23

Maximum deflections now defined for beams, joists and decking for SDD decks
 
• Section 9.5 Design of Area and Spaces

Combination rooms - description has been clarified to determine what can be classified as a combination room.

Now requires a minimum 3m² (32 sq.ft.) opening or 40% of dependant room wall, whichever is greater, with no doors or windows in the openings. Direct access is required between rooms if it is a bedroom.
 
• Barrier free – main bathroom in a dwelling unit shall now have reinforcement in the stud wall for future installation of grab bars adjacent to toilet and shower or bathtub (see 3.8.3.8(1)(d) and 3.8.3.13(1)(f) for specific locations)

• Section 9.7 Windows and Skylights

• Windows over stairs, ramps and landings that extend to less than 900mm (2’-11”) above the surface now have to be protected by a guard or be non-operable and designed for lateral loads
 
• Section 9.8 Stairs, Ramps, Handrails and Guards

• Tolerances of 6mm (1/4”) between adjacent treads and risers now permitted.
 
• Section 9.8 Stairs, Ramps, Handrails and Guards

·          Finishes for stair treads – now defined for dwelling units (and includes low pile carpet)

·          Landings – Clarification that a landing is NOT required for the stair from the garage to the main house provided the door swings away from the stair (regardless of number of risers). There is also a Ministry opinion on this.

·          Ergonomic design – clearance of handrails increased from

40mm (1 9/16”) to 50mm (2”)

·          Attachment of handrail – first attachment point for handrails to be maximum 300mm (11 ¾”) from each end
 
·         Basement stair guard – guards (or walls) are now required on both sides of basement stairs

·         Guard design – additional requirements to permit the use ornamental designs that could be considered non-climbable

·         Height of guard – minimum height of guard for dwelling unit now standardized at 900mm (2’-11”) including guards on stairs [previously allowed 800mm (2’-7”)]
 

• Guard required if slope on surface adjacent to stair, landing, porch, deck, etc is more than 1 in 2 (6 in 12) and within 1.2m (3’-11”)
 

• Section 9.10 Fire Protection

• Gasproofing of garage – now permits the use of membrane air barrier material provided all joints seals and structurally supported

• Limiting distance and construction of exposing building faces have been expanded for houses under a new sub-section 9.10.15.
 

• Semi-rigid insulation required between double frame wall assemblies (townhouse units) extending from below the bottom of the top plates in the lower storey to above the top of the bottom plate in the upper storey.
 
New – double framed wall assembly at header location

Semi-rigid fibre insulation board (density of not less than 45 kf/m ³ ) fastened to one set of studs required as fire stop.
 
 
• Section 9.15 Footings and Foundations

Reinforced Concrete block walls – new table for design outside of Part 4

ICF (see also 9.20) – design criteria for FLAT insulating concrete form walls – limited to SFD

Step footings – now required to be 600mm vertical regardless of soil type

• Article 9.19.2.1 Access to Roof Spaces

·         Attic access hatches serving single dwelling units shall be a minimum 0.32m² (3.44 sq.ft.) with no dimension less than 545 mm (21.5”). This will require a minimum 545mm (21.5”) x 587mm (23”) attic access hatch
 
 
• Section 9.20 Masonry and ICF Walls Above Ground

·     New Table 9.20.5.2.C. for steel beams only supporting masonry veneer. Note: steel posts required for support

·     New subsection 9.20.17. for ICF wall design criteria

• Section 9.23 Wood Frame Construction

·     Steel beam spans – some slight increases of spans for specific steel beams

·     Tall wall tables – new tables A30 – A33. See also the construction requirements under 9.23.10.1

·     New tables A34 to A37 specifying the number of studs required under the ends of beams and girder trusses. See also the construction requirements under 9.23.10.7
 

• Section 9.25 Heat Transfer, Air Leakage and Condensation Control

·         Insulation values moved to new Part 12 (covered later)

·       Vapour barrier must be designed and located according to OBC

Part 5 if the relative humidity is to be maintained above 35% over the heating season OR if the intended use of the interior space results in an average monthly indoor relative humidity of 35% over the heating season and for which the ventilation and a/c system does not have the capacity to reduce it

 • Section 9.26 Roofing

·       Slope roof criteria to ensure no water ingress to structure and also requiring positive slope after anticipated building frame shrinkage

·       Valley flashing now required over continuous sheathing
 
· Section 9.27 Cladding

·         First and second planes of protection against ingress of precipitation which also requires flashing. If insulated sheathing is used the joints need to be sealed if it is not tongue and grooved or lapped.

·            Section 9.32 Ventilation

·         Clothes dryer exhaust installation shall conform to Part 6

·      Section 9.40 Reinforced Concrete Slabs

·         New design requirements for reinforced slabs over cold rooms (maximum 2.5m (8’-2”) wide) in lieu of Part 4 design
 

• Part 12 – Resource Conservation
 
·      As of Jan 1, 2007 – Houses Insulation to 12.3.2, or

·      Thermal Design to 12.3.3 (was previously 9.38), or

·      Energuide 80 Rating

·      After Jan 1, 2012 – Houses

·      Energuide 80 Rating only

·      Equipment – As of Jan 1, 2007 – Houses

·      Natural Gas or Propane furnace – 90% minimum efficiency

·      Oil furnace – not regulated in OBC
 
 
• As of Jan 1, 2007 – House Insulation Value

·      Ceiling (with roof space) – R40 (from R31)

·      Roof (no roof space) – R28 (from R20)

·     Wall – R19 (from R17)

·     Foundation – R12 (from R8)

·      Floors/slabs – no change

• Foundation Insulation

·    Until December 31, 2008 – no change to current requirement of insulation to 600mm below grade

·   After January 1, 2009 – foundation insulation will be required to come down to a maximum of 380mm above basement floor
 
 
• Windows as of January 1, 2007
All windows to meet energy ratings of 17ER for operating windows and 27ER for fixed as determined by CAN/CSA – A440.2 (verify with your window supplier)
 
• As of Jan 1, 2012 – Energuide for New Houses

·         Prescriptive requirements for insulation no longer apply

·    House must have a minimum rating of 80 as tested in conformance with the energuide for new houses