Section 1 General

1.1. Introduction

1.1.1. Scope (See Appendix A.)

  1. This Supplementary Standard includes details for the construction of wood guards.
  2. Guards located on the exterior of a building, where they may be subject to deterioration, shall be constructed in accordance with Section 2 of this Supplementary Standard. (See Appendix A.)
  3. Guards located inside a building shall be constructed in conformance with Section 2 or Section 3 of this Supplementary Standard.

1.2. Design of Guards

1.2.1. Cantilever Action (See Appendix A.)

  1. The construction details for guards in this Supplementary Standard are based on the assumption that the guard acts as a cantilever in resisting lateral loads.

1.2.2. Classification (See Appendix A.)

  1. The structural systems of guards described in this Supplementary Standard are grouped into the following classifications:
  1. Post and Rail Systems, and
  2. Cantilevered Picket Systems.

Section 2 Exterior Guards

2.1. Materials

2.1.1. Lumber Grades (See Appendix A)

  1. The minimum grade of softwood dimension lumber for posts, rails and joists shall be Northern Species, No. 2.
  2. The minimum grade of softwood dimension lumber for pickets shall be Northern Species, No. 2 Picket grade.
  3. Wood for pickets shall be free of loose knots.

2.1.2. Lumber Dimensions

  1. Except as permitted in Sentence (2), the minimum sizes of loadbearing elements of wood guards shall conform to Table 2.1.2.

Table 2.1.2. Minimum Size of Loadbearing Elements

Table 2.1.2. — Minimum Size of Loadbearing Elements
Guard ElementMinimum Size, mm (in)
Post89 x 89 (4" x 4" nominal)
Top Rail38 x 89 (2" x 4" nominal)
Bottom Rail38 x 89 (2" x 4" nominal)
Picket / Baluster32 x 32 (19/32" x 19/32")
Column 12
  1. Where a bottom rail is bevelled, the minimum sizes shown in Table 2.1.2. may be reduced to allow for a bevel, as detailed in Figure 2.1.2.
Figure 2.1.2. Bevel Detail

Dimensional diagram of a pentagonal wood ridge cap cross-section measuring 89 mm wide by 38 mm tall with a 20-degree angled top.

2.1.3. Floor Construction (See Appendix A.)

  1. The minimum dimensions of wood floor joists and wood decking shall conform to Table 2.1.3.
  2. Except as provided in Details EA-1 to ED-5, wood decking shall be fastened to each floor joist with nailing conforming to Table 2.1.3.

Table 2.1.3. Minimum Size of Floor Elements

Table 2.1.3. — Minimum Size of Floor Elements
Floor ElementMinimum Size, mm (in)
Dimension Lumber Decking25 x 140 (5/4" x 6" nominal), when each plank is fastened with 2 - 63 mm (2½") nails
Dimension Lumber Decking38 x 89 (2" x 4" nominal), when each plank is fastened with 2 - 76 mm (3") nails
Dimension Lumber Joists38 x 184 (2" x 8" nominal)
Column 12

2.1.4. Connectors (See Appendix A.)

  1. Nails, screws, lag bolts and machine bolts shall not cause splitting of wood elements.
  2. Fasteners shall be resistant to corrosion.
  3. All nails shall be common spiral.

(See also A-2.1.4. in Appendix A for glued joints.)

2.1.5. Decay-Resistant Lumber (See Appendix A.)

  1. Lumber for guard systems and floor systems shall be
    1. a species resistant to decay,
    2. preservative treated to prevent decay, or
    3. pressure-treated.
  2. All cut ends of preservative treated lumber shall be treated to prevent decay.

2.2. Structural Details

2.2.1. Post and Rail System

  1. An exterior guard constructed as a Post and Rail System shall conform to the applicable connection details listed in Table 2.2.1.

2.2.2. Cantilevered Picket System

  1. An exterior guard constructed as a Cantilevered Picket System shall conform to the applicable connection details listed in Table 2.2.2.

Table 2.2.1. Exterior Post and Rail System Connection Details

Table 2.2.1. — Exterior Post and Rail System Connection Details
Connection DetailDetail NumberDescription
Top Rail to Post — and / or — Bottom Rail to PostEA-1Top rail nailed to post
Top Rail to Post — and / or — Bottom Rail to PostEA-2Top/bottom rail skew nailed to post with 76 mm (3") nails
Top Rail to Post — and / or — Bottom Rail to PostEA-3Top/bottom rail skew nailed to post with 63 mm (21/2") nails
Top Rail to Post — and / or — Bottom Rail to PostEA-4Top/bottom rail face nailed or screwed to post
Top Rail to Post — and / or — Bottom Rail to PostEA-5Top/bottom rail fastened to post with framing anchors
Post to FloorEB-1Post nailed to rim joist
Post to FloorEB-2Post screwed to rim joist
Post to FloorEB-3Post bolted to floor joist with 8 mm (5/16") machine bolts
Post to FloorEB-4Post bolted to floor joist with 9.5 mm (3/8") machine bolts
Post to FloorEB-5Post bolted to 2 floor joists
Post to FloorEB-6Post fastened to floor, where guard is parallel to floor joists
Infill PicketEC-1Picket nailed to endcap; endcap screwed to rail
Infill PicketEC-2Picket nailed to rail
Infill PicketEC-3Picket screwed to rail
Infill PicketEC-4Picket screwed to top rail and rim joist
Column 123

Table 2.2.2. Exterior Cantilevered Picket System Connection Details

Table 2.2.2. — Exterior Cantilevered Picket System Connection Details
Connection DetailDetail NumberDescription
Cantilevered Picket — (Douglas Fir-Larch, Spruce-Pine-Fir, Hem-Fir Species)ED-1Picket screwed to rim joist
Cantilevered Picket — (Douglas Fir-Larch, Spruce-Pine-Fir, Hem-Fir Species)ED-2Picket screwed to rim joist, where guard is parallel to floor joists
Cantilevered Picket — (Northern Species)ED-3Picket screwed to rim joist and deck
Cantilevered Picket — (Northern Species)ED-4Picket screwed to rim joist and deck, where guard is parallel to floor joists
Cantilevered Picket — (Douglas Fir-Larch, Spruce-Pine-Fir, Hem-Fir Species, Northern Species)ED-5Corner
Column 123

Section 3 Interior Guards

3.1. Materials

3.1.1. Lumber and Wood Products

  1. Lumber species used for a primary loadbearing element in a guard shall be a species listed in the Table 3.1.2.
  2. Except as provided in Sentence (4), the minimum grade of softwood dimension lumber for posts, rails and joists shall be Northern Species, No. 2.
  3. Except as provided in Sentence (4), the minimum grade of softwood dimension lumber for cantilevered pickets shall be Northern Species, No. 2 Picket grade.
  4. White pine and hemlock lumber used for posts, rails and non-cantilevered pickets shall be clear straight grain material.
  5. Oak, maple and yellow poplar lumber used for posts, rails and pickets shall be clear straight grain material.

3.1.2. Lumber Dimensions

  1. The minimum sizes of loadbearing elements of wood guards shall conform to Table 3.1.2.

3.1.3. Floor Construction

  1. The minimum dimensions of wood floor joists and wood subflooring shall conform to Table 3.1.3. (See A-2.1.3. in Appendix A.)

3.1.4. Connectors

  1. Nails, screws, lag bolts and machine bolts shall not cause splitting of the wood elements. (See A-2.1.4. in Appendix A.) (See also A-2.1.4. in Appendix A for glued joints.)

3.2. Structural Details

3.2.1. Post and Rail System

  1. An interior guard constructed as a Post and Rail System shall conform to the applicable connection details listed in Table 3.2.1.

3.2.2. Cantilevered Picket System

  1. An interior guard constructed as a Cantilevered Picket System shall conform to the applicable connection details listed in Table 3.2.2.

3.2.3. Guards for Stairs

  1. An interior guard for a stair shall conform to the appropriate connection details listed in Table 3.2.3.

Table 3.1.2. Minimum Size of Loadbearing Elements

Table 3.1.2. — Minimum Size of Loadbearing Elements
Guard ElementSpeciesMinimum Size, mm (in)Detail Number(1)
PostOak, Maple70 x 70 (23/4" x 23/4") Base, 45 (13/4") Turned DiameterIB-1, IG-1, IG-2, IG-3
PostHemlock, White Pine, Yellow Poplar82 x 82 (31/4" x 31/4") Base, 50 (2") Turned DiameterIB-1, IG-1, IG-2, IG-3
Post in a VoluteOak, Maple70 x 70 (23/4" x 23/4") Base, 50 (2") Turned DiameterIG-4
Top RailOak, Maple41 x 67 (15/8" x 25/8")IA-1, IF-1
Bottom RailOak, Maple41 x 67 (15/8" x 25/8") 19 x 67 (3/4" x 25/8"), if continuously supportedIA-1, IF-1
Infill PicketOak, Maple20 (3/4") DiameterIC-1, IC-2
Infill PicketYellow Poplar22 (7/8") DiameterIC-1, IC-2
Infill PicketWhite Pine, Hemlock24 (31/32") DiameterIC-1, IC-2
Picket in a VoluteOak, Maple32 x 32 (19/32" x 19/32") Base, 20 (3/4") Turned DiameterIG-4
Picket in a VoluteYellow Poplar45 x 45 (13/4" x 13/4") Base, 22 (7/8") Turned DiameterIG-5, IG-6
Picket in a VoluteWhite Pine, Hemlock45 x 45 (13/4" x 13/4") Base, 24 (31/32") Turned DiameterIG-5, IG-6
Cantilevered PicketNorthern Species, Douglas Fir-Larch, Spruce-Pine-Fir, Hem-Fir, Hardwood32 x 32 (19/32" x 19/32")IE-1, IH-1
Column 1234

Notes to Table 3.1.2.:

1. This column lists details that incorporate the guard elements specified in this Table. ↑

Table 3.1.3. Minimum Size of Floor Elements

Table 3.1.3. — Minimum Size of Floor Elements
Floor ElementMinimum Size, mm (in)
Subfloor15.5 (5/8") plywood or equivalent
Dimension Lumber Joists38 x 184 (2" x 8" nominal)
Column 12

Table 3.2.1. Interior Post and Rail System Connection Details

Table 3.2.1. — Interior Post and Rail System Connection Details
Connection DetailDetail NumberDescription
Top and/or Bottom Rail to PostIA-1Rail glued and screwed to post
Post to FloorIB-1Notched post glued and bolted to rim joist
Infill PicketIC-1Picket set into rails
Infill PicketIC-2Picket dowelled into rails
Stud WallID-1Wood stud and gypsum board
Column 123

Table 3.2.2. Interior Cantilevered Picket System Connection Details

Table 3.2.2. — Interior Cantilevered Picket System Connection Details
Connection DetailDetail NumberDescription
Picket to FloorIE-1Picket screwed to rim joist
Column 123

Table 3.2.3. Interior Stair Guard Connection Details

Table 3.2.3. — Interior Stair Guard Connection Details
Connection DetailDetail NumberDescription
Rail to PostIF-1Top or bottom rail glued and screwed to post
Post to Floor — and/or — Picket Volute to FloorIG-1Notched post glued and screwed to stringer and riser
Post to Floor — and/or — Picket Volute to FloorIG-2Post glued and screwed to stringer
Post to Floor — and/or — Picket Volute to FloorIG-3Post glued and screwed to stringer and stud wall
Post to Floor — and/or — Picket Volute to FloorIG-4Post and picket volute, oak or maple
Post to Floor — and/or — Picket Volute to FloorIG-5Picket volute, 260 mm (101/4") wide
Post to Floor — and/or — Picket Volute to FloorIG-6Picket volute, 240 mm (91/2") wide
Infill PicketIC-1 or IC-2Detail IC-1 or IC-2 in Table 3.2.1., modified to suit a sloping installation, may be used.
Cantilevered PicketIH-1Picket screwed to stair stringer
Column 123

Detail EA-1 — Exterior Connection: Top Rail Nailed to Post

Detail EA-1 composite construction diagram. The first view is a plan-view cross-section showing two wood post-and-beam connections, each with bolted top rail connectors enclosed within dashed boundary boxes. The second view is an axonometric drawing showing two T-shaped wood post-and-beam assemblies side by side, each with a horizontal rail mortised into the top of a vertical post and bolt holes indicated. The third view is an elevation diagram showing a row of wood pickets nailed to horizontal rails, with four 76 mm nails at each connection point, spanning between two posts shown in cross-section. The fourth view is an elevation diagram showing a single wood guard post with the top rail assembly labeled at the top, the vertical member labeled as the post, and the footing shown in cross-section.

Notes:

  1. The top rail must be continuous. Use Detail EA-5 at the end spans, where continuity ends.
Maximum Span of Rail Between Posts
Maximum Span of Rail Between Posts
SpeciesMaximum Span, m (ft-in)
Douglas Fir-Larch, Hem-Fir, Spruce-Pine-Fir1.52 (5'-0")
Northern Species1.52 (5'-0")
Column 12

Detail EA-2 — Exterior Connection: Top/Bottom Rail Skew Nailed to Post - 76 mm (3") Nails

Detail EA-2 composite construction diagram. The first view is a plan-view construction diagram of a post-and-rail connection, showing a post and rail assembly fastened with two 76 mm nails per connection. The second view is an axonometric construction drawing showing a wood post with top and bottom horizontal rails mortised into it on alternating sides, with fastener holes indicated at each connection. The third view is an elevation diagram showing two wood post-to-rail connection details, each specifying a gap of at least 12 mm and not more than 19 mm between the rail and the post face. The fourth view is an elevation diagram showing a wood guard post with two horizontal rails attached at mid-height and lower positions, with both horizontal members labeled as rails.

Notes:

  1. The maximum span is more often governed by post spacing.
  2. Provide support to bottom rail at intervals not more than 2.0 m (6'-7").
  3. The bottom rail may be bevelled as detailed in Figure 2.1.2.
  4. Dimensions shown are in mm unless otherwise specified.
Maximum Span of Rail Between Posts
Maximum Span of Rail Between Posts
SpeciesMaximum Span, m (ft-in)
Douglas Fir-Larch, Hem-Fir, Spruce-Pine-Fir2.72 (8'-11")
Northern Species2.18 (7'-2")
Column 12

Detail EA-3 — Exterior Connection: Top/Bottom Rail Skew Nailed to Post - 63 mm (2½") Nails

Detail EA-3 composite construction diagram. The first view is a plan-view construction diagram of a post-and-rail connection, showing a post and rail assembly fastened with three 63 mm, or 2.5 inch, nails per connection. The second view is an axonometric construction drawing showing a wood post with top and bottom horizontal rails mortised into alternate sides, with bolt holes shown at each connection point. The third view is an elevation diagram showing two wood post-to-rail connection details, each specifying a gap of at least 12 mm and not more than 19 mm between the rail and the post face. The fourth view is an elevation diagram showing a wood guard post with two horizontal rails attached at different heights, with the horizontal members labeled as rails and the post shown in cross-section at the top and bottom.

Notes:

  1. Provide support to bottom rail at intervals not more than 2.0 m (6'-7").
  2. The bottom rail may be bevelled as detailed in Figure 2.1.2.
  3. Dimensions shown are in mm unless otherwise specified.
Maximum Span of Rail Between Posts
Maximum Span of Rail Between Posts
SpeciesMaximum Span, m (ft-in)
Douglas Fir-Larch, Hem-Fir, Spruce-Pine-Fir2.72 (8'-11")
Northern Species2.18 (7'-2")
Column 12

Detail EA-4 — Exterior Connection: Top/Bottom Rail Face Nailed or Screwed to Post

Detail EA-4 composite construction diagram. The first view is a plan-view construction diagram labeled Deck Side, showing two posts connected by rails, with two number 8 by 76 mm screws fastening each post to the rail at each connection. The second view is an axonometric construction drawing showing two wood post-and-rail corner connections, with each rail notched and screwed into the side face of the post. The third view is an elevation diagram showing two wood guard posts connected by a horizontal rail, with a 50 mm dimension labeled and bolt holes indicated on each post. The fourth view is an elevation diagram showing a single wood guard post with a horizontal rail attached at mid-height using a bolted connection detail, with the horizontal member labeled as rail.

Notes:

  1. If the rails are located on the deck side of the posts, 76 mm (3") nails may be used in place of the screws.
  2. Where the top rail is continuous, the top rail may be fastened to each post with 3 - #8 x 76 mm (3") screws.
  3. Dimensions shown are in mm unless otherwise specified.
Maximum Span of Rail Between Posts
Maximum Span of Rail Between Posts
SpeciesMaximum Span, m (ft-in)
Douglas Fir-Larch, Hem-Fir, Spruce-Pine-Fir1.77 (5'-10")
Northern Species1.41 (4'-8")
Column 12

Detail EA-5 — Exterior Connection: Top/Bottom Rail Fastened to Post with Framing Anchors

Multi-view construction diagram showing plan, axonometric, front elevation, and side elevation of a post-to-rail connection using a minimum 20-gauge corrosion-resistant framing anchor fastened with manufacturer-recommended nails.

Notes:

  1. Provide support to bottom rail at intervals not more than 2.0 m (6'-7").
  2. The bottom rail may be bevelled as detailed in Figure 2.1.2.
  3. Dimensions shown are in mm unless otherwise specified.
Maximum Span of Rail Between Posts
Maximum Span of Rail Between Posts
SpeciesMaximum Span, m (ft-in)
Douglas Fir-Larch, Hem-Fir, Spruce-Pine-Fir2.72 (8'-11")
Northern Species2.18 (7'-2")
Column 12

Detail EB-1 — Exterior Connection: Post Nailed to Rim Joist

Multi-view construction diagram showing plan, axonometric, front elevation, and side elevation of a deck post base connection using floor joist, rim joist, and post with nailing and dimension specifications.

Notes:

  1. Decking is omitted from the plan view and the axonometric view for clarity.
  2. Fasten 25 mm x 140 mm (5/4" x 6" nominal) outer deck board to rim joist with 63 mm (2½") nails at 300 mm (12").
  3. Fasten 25 mm x 140 mm (5/4" x 6" nominal) outer deck board to floor joist with 1 - 63 mm (2½") nail at each joist.
  4. The post may be positioned anywhere between the joists.
  5. Dimensions shown are in mm unless otherwise specified.
Maximum Span of Rail Between Posts
Maximum Span of Rail Between Posts
SpeciesMaximum Span, m (ft-in)
Douglas Fir-Larch, Hem-Fir, Spruce-Pine-Fir1.22 (4'-0")
Northern Species1.20 (3'-11")
Column 12

Detail EB-2 — Exterior Connection: Post Screwed to Rim Joist

Multi-view construction diagram showing plan, axonometric, front elevation, and side elevation of a deck post-to-rim-joist connection fastened with 4 nails of 76 mm and 4 screws of number 9 by 76 mm per side.

Notes:

  1. Decking is omitted from the plan view and the axonometric view for clarity.
  2. Fasten 25 mm x 140 mm (5/4" x 6" nominal) outer deck board to rim joist with 63 mm (2½") nails at 300 mm (12").
  3. Fasten 25 mm x 140 mm (5/4" x 6" nominal) outer deck board to floor joist with 1 - 63 mm (2½") nail at each joist.
  4. The post may be positioned anywhere between the joists.
  5. #9 screws may be replaced by #8 screws if the maximum spacing between posts is not more than 1.20 m (3'-11").
  6. Dimensions shown are in mm unless otherwise specified.
Maximum Span of Rail Between Posts
Maximum Span of Rail Between Posts
SpeciesMaximum Span, m (ft-in)
Douglas Fir-Larch, Hem-Fir, Spruce-Pine-Fir1.56 (5'-1")
Northern Species1.20 (3'-11")
Column 12

Detail EB-3 — Exterior Connection: Post Bolted to Floor Joist - 8 mm (5/16") Bolts

Multi-view construction diagram showing plan, axonometric, front elevation, and side elevation of a deck post connection to floor joist and rim joist using machine bolts with fender washers and nails with specified dimensions.

Notes:

  1. Decking is omitted from the plan view and the axonometric view for clarity.
  2. 38 mm (1½") post projection is not required where the maximum spacing between posts does not exceed 1.20 m (3'-11").
  3. Joists may be spaced at 610 mm (24") o.c. or 406 mm (16") o.c.
  4. Where floor joists are spaced at 610 mm (24") o.c., decking shall have a minimum thickness of 38 mm (1½") and shall be fastened to the floor with 2 - 76 mm (3") nails.
  5. Dimensions shown are in mm unless otherwise specified.
Maximum Spacing Between Posts
Maximum Span of Rail Between Posts
SpeciesMaximum Span, m (ft-in)
Douglas Fir-Larch, Hem-Fir, Spruce-Pine-Fir1.29 (4'-3")
Northern Species1.20 (3'-11")
Column 12

Detail EB-4 — Exterior Connection: Post Bolted to Floor Joist - 9.5 mm (3/8") Bolts

Multi-view construction diagram showing plan, axonometric, front elevation, and side elevation of a deck corner post connection to rim joist and floor joist using 9.5 mm machine bolts with fender washers and nails.

Notes:

  1. Decking is omitted from the plan view and the axonometric view for clarity.
  2. 38 mm (1½") post projection is not required where the maximum spacing between posts does not exceed 1.20 m (3'-11").
  3. Joists may be spaced at 610 mm (24") o.c. or 406 mm (16") o.c.
  4. Where floor joists are spaced at 610 mm (24") o.c., decking shall have a minimum thickness of 38 mm (1½") and shall be fastened to the floor with 2 - 76 mm (3") nails.
  5. Dimensions shown are in mm unless otherwise specified.
Maximum Spacing Between Posts
Maximum Span of Rail Between Posts
SpeciesMaximum Span, m (ft-in)
Douglas Fir-Larch, Hem-Fir, Spruce-Pine-Fir1.49 (4'-11")
Northern Species1.20 (3'-11")
Column 12

Detail EB-5 — Exterior Connection: Post Bolted to 2 Floor Joists

Multi-view construction diagram showing plan, axonometric, front elevation, and side elevation of a deck post connection to rim joist and floor joist using 9.5 mm by 205 mm machine bolts with fender washers and 82 mm nails.

Notes:

  1. Decking is omitted from the plan view and the axonometric view for clarity.
  2. 38 mm (1½") post projection is not required where the maximum spacing between posts does not exceed 1.20 m (3'-11").
  3. Joists may be spaced at 610 mm (24") o.c. or 406 mm (16") o.c.
  4. Where floor joists are spaced at 610 mm (24") o.c., decking shall have a minimum thickness of 38 mm (1½") and shall be fastened to the floor with 2 - 76 mm (3") nails.
  5. Dimensions shown are in mm unless otherwise specified.
Maximum Spacing Between Posts
Maximum Span of Rail Between Posts
SpeciesMaximum Span, m (ft-in)
Douglas Fir-Larch, Hem-Fir, Spruce-Pine-Fir2.14 (7'-0")
Northern Species1.20 (3'-11")
Column 12

Detail EB-6 — Exterior Connection: Post Fastened to Floor, Guard Parallel to Floor Joists

Multi-view construction diagram showing plan, axonometric, elevation B-B, and elevation C-C of an interior deck post connection to rim joist and floor joist with blocking, using 82 mm nails with specified dimensions.

Notes:

  1. Use any of the connection details shown on Details EB-1 to EB-5 at location “A”. Connection Detail EB-4 is shown in this detail, as an example.
  2. Maximum spacing between posts is determined from connection detail used at location “A”.
  3. Decking is omitted from the plan view and the axonometric view for clarity.
  4. Blocking shall be not less than 38 mm x 184 mm (2" x 8" nominal).
  5. Dimensions shown are in mm unless otherwise specified.

Detail EC-1 — Exterior Connection: Infill Picket Nailed to Endcap - Endcap Screwed to Rail

Detail EC-1 composite construction diagram. The first view shows plan and axonometric views of a wood guard assembly with a bottom rail, endcaps and pickets, illustrating how the rail connects to the post. The second view shows front and side elevations of the wood picket guard assembly, focusing on the bottom rail connection detail. It identifies number 7 by 50 mm screws, two 50 mm nails, and a 19 mm by 38 mm endcap used at the connection.

Notes:

  1. Fasten each end of each picket to endcaps with 2 - 50 mm (2") nails.
  2. Fasten endcaps to rails with #7 x 50 mm (2") screws at 300 mm (12") o.c.
  3. See Table 2.1.2. for minimum sizes of pickets.

Detail EC-2 — Exterior Connection: Infill Picket Nailed to Rail

Detail EC-2 composite construction diagram. The first view is a plan-view detail labeled Rail and Picket, showing a horizontal rail with two square pickets attached below it in cross-section. The second view is an axonometric construction drawing of a complete wood guard assembly, showing a top rail, two vertical pickets with endcaps, and a bottom rail, all connected to posts. The third view is a front elevation diagram of the wood guard assembly, showing two vertical posts with a top rail and bottom rail connected between them, with pickets spanning between the posts. The fourth view is a side elevation detail of a wood picket guard, showing the top rail, a 19 mm by 32 mm blocking piece, and two finishing nail specifications for connecting the picket to the rail.

Notes:

  1. See Table 2.1.2. for minimum sizes of pickets.
  2. Dimensions shown are in mm unless otherwise specified.

Detail EC-3 — Exterior Connection: Infill Picket Screwed to Rail

Detail EC-3 composite construction diagram. The first view is a plan-view construction detail labeled Deckside, showing a rail with two pickets below it, fastened with number 7 by 63 mm screws at each connection. The second view is an axonometric construction drawing of a wood guard assembly, showing a top cap rail, two vertical pickets with endcaps, and a bottom rail connected to posts on both sides. The third view is a front elevation diagram of the wood guard assembly, showing two posts with top and bottom rails and vertical pickets spanning between them, with bolt holes shown on each post. The fourth view is a side elevation diagram of a wood guard post, showing the top rail and bottom rail connection, with the picket attached to the face of the post.

Detail EC-4 — Exterior Connection: Infill Picket Screwed to Top Rail and Rim Joist

Multi-view construction diagram showing deckside plan, axonometric, front elevation, and side elevation of a wood guard assembly with top rail, rail, pickets, and rim joist connections with specified screw and nail fasteners.

Note:

  1. Dimensions shown are in mm unless otherwise specified.

Detail ED-1 — Exterior Connection: Cantilevered Picket Screwed to Rim Joist

Multi-view construction diagram showing plan, axonometric, front elevation, and side elevation of a wood guard assembly attached to a rim joist with pickets, top rail, and specified screw connections at 300 mm and 200 mm spacings.

Notes:

  1. Provide a suitable post, return, or solid support at each end of the guard.
  2. Wood for cantilevered pickets shall be Douglas Fir-Larch, Spruce-Pine-Fir, or Hem-Fir Species.
  3. Fasten rim joist to each floor joist with 3 - 82 mm (3¼") nails.
  4. Dimensions shown are in mm unless otherwise specified.
  5. The outer deck board shall not be less than 140 mm (6" nominal) wide. Where 38 mm (2" nominal) thick boards are used, the length of the wood screws shall be not less than 76 mm (3").

Detail ED-2 — Exterior Connection: Cantilevered Picket Screwed to Rim Joist, Guard Parallel to Floor Joists

Multi-view construction diagram showing plan, axonometric, front elevation, and side elevation of a wood guard assembly with pickets attached to blocking at 400 mm spacing, connected to a rim joist with specified screws.

Notes:

  1. Provide a suitable post, return, or solid support at each end of the guard.
  2. Wood for cantilevered pickets shall be Douglas Fir-Larch, Spruce-Pine-Fir, or Hem-Fir Species.
  3. Fasten rim joist to blocking with 3 - 82 mm (3¼") nails.
  4. Dimensions shown are in mm unless otherwise specified.
  5. Where 38 mm (2" nominal) thick boards are used, the length of the wood screws shall be not less than 76 mm (3").

Detail ED-3 — Exterior Connection: Cantilevered Picket Screwed to Rim Joist and Deck

Multi-view construction diagram showing plan, axonometric, front elevation, and side elevation of a wood guard assembly with pickets screwed to outer deck boards and rim joist at specified spacings.

Notes:

  1. Provide a suitable post, return, or solid support at each end of the guard.
  2. Wood for cantilevered pickets shall be Northern Species.
  3. Fasten rim joist to each floor joist with 3 - 82 mm (3¼") nails.
  4. Dimensions shown are in mm unless otherwise specified.

Detail ED-4 — Exterior Connection: Cantilevered Picket Screwed to Rim Joist and Deck, Guard Parallel to Floor Joists

Multi-view construction diagram showing plan, axonometric, front elevation, and side elevation of a wood guard assembly with pickets connected to 38 by 140 mm boards and rim joist with specified screw fasteners and blocking.

Notes:

  1. Provide a suitable post, return, or solid support at each end of the guard.
  2. Wood for cantilevered pickets shall be Northern Species.
  3. Fasten rim joist to blocking with 3 - 82 mm (3¼") nails.
  4. Dimensions shown are in mm unless otherwise specified.

Detail ED-5 — Exterior Connection: Corner Joint

Detail ED-5 composite construction diagram. The first view shows a plan-view top rail detail and an axonometric view of a corner wood guard assembly. It identifies three number 8 by 76 mm screws at the top rail connection and shows the corner assembly in three dimensions with multiple vertical pickets and a cap rail wrapping around the corner. The second view shows front and side elevation diagrams of the corner wood guard top rail connection, illustrating how the rail is fastened to the post from both the front and side views.

Notes:

  1. Screws fastening pickets are omitted for clarity.
  2. Provide a minimum of 10 pickets beyond the return if end restraint of the guard is provided by this return detail only.

Detail IA-1 — Interior Connection: Rail Glued and Screwed to Post

Multi-view construction diagram showing plan, top rail section, axonometric, front elevation, and side elevation of a rounded wood handrail glued to a post, with 67 mm wide by 41 mm tall rail profile and number 10 by 89 mm screw fastening.

Notes:

  1. Other top rail systems may be used provided the section modulus is not less than 24,000 mm3, measured about the x-x axis.
  2. Pickets omitted on drawing for clarity.
  3. Connection details for fastening of pickets to rails are shown on Details IC-1 and IC-2.
  4. Dimensions shown are in mm unless otherwise specified.
Maximum Span of Rail Between Posts
Maximum Span of Rail Between Posts
SpeciesMaximum Span, m (ft-in)
Oak, Maple3.30 (10'-10")
Column 12

Detail IB-1 — Interior Connection: Notched Post Glued and Bolted to Rim Joist

Detail IB-1 composite construction diagram. The first view shows plan and axonometric views of a wood post glued and nailed to a floor joist, with the connection fastened using three 82 mm nails. The second view shows an elevation and detailed section of a deck post base connection, with a 9.5 mm bolt and fender washers passing through the decking into the post. The diagram labels a post height of 184 mm and an embedment depth of 150 mm at the base connection.

Notes:

  1. Minimum dimension of post is 82 mm x 82 mm (3¼" x 3¼").
  2. Notch post 38 mm x 152 mm (1½" x 6") at rim joist.
  3. Dimensions shown are in mm unless otherwise specified.
Maximum Spacing Between Posts
Maximum Spacing Between Posts
Post SpeciesMaximum Span, m (ft-in)
Oak, Maple, Yellow Poplar, Hemlock, White Pine3.30 (10'-10")
Column 12

Detail IC-1 — Interior Connection: Infill Picket Set into Rails

Multi-view construction diagram showing plan, axonometric, front elevation, and side elevation of a wood guard assembly with vertical pickets connected to top and bottom rails using 2 finishing nails and a spacer detail.

Notes:

  1. See Table 3.1.2. for minimum sizes of pickets.
  2. For top and bottom rail provide 6 mm (1/4") deep rabbet.

Detail IC-2 — Interior Connection: Infill Picket Dowelled into Rails

Multi-view construction diagram showing plan, axonometric, front elevation, and side elevation of a wood guard assembly with vertical pickets connected to top and bottom rails using 19 mm diameter dowels.

Notes:

  1. See Table 3.1.2 for minimum sizes of pickets.
  2. Pickets dowelled 19 mm (3/4") deep into rails with 19 mm (3/4") diameter dowels.

Detail ID-1 — Interior Connection: Wood Stud and Gypsum Board Guard

Multi-view construction diagram showing plan, axonometric, front elevation, and side elevation of a wood guard post attached through gypsum board to 38 by 89 mm wood studs and a top plate using nails and screws.

Notes:

  1. Fasten plywood subfloor to joists with 50 mm (2") nails at 150 mm (6") oc along edges and at 300 mm (12") oc along intermediate supports.
  2. Gypsum board omitted on plan, front elevation, and axonometric for clarity.
  3. Dimensions shown are in mm unless otherwise specified.
  4. Provide a suitable post, return, or solid support at each end of the guard.
Maximum Spacing Between Wood Studs
Maximum Spacing Between Wood Studs
Stud SpeciesMaximum Spacing, mm (in)
Douglas Fir-Larch, Hem-Fir, Spruce-Pine-Fir, Northern Species406 (16")
Column 12

Detail IE-1 — Interior Connection: Cantilevered Picket Screwed to Rim Joist

Detail IE-1 composite construction diagram. The first view shows plan and axonometric views of a stair landing guard post assembly, with the post attached through the landing structure using bolt connections. The second view shows construction elevation and side elevation diagrams of the stair guard post connection, with the post fastened to a 45 mm by 138 mm top rail and a 38 mm by 184 mm floor joist using countersunk screws.

Notes:

  1. Provide a suitable post, return, or solid support at each end of the guard.
  2. See Table 3.1.2. for minimum sizes of pickets.
  3. Dimensions shown are in mm unless otherwise specified.
  4. Rim joist and top rail of oak or maple.

Detail IF-1 — Interior Stair Guard Connection: Top/Bottom Rail Glued and Screwed to Post

Multi-view construction diagram showing plan, top rail section, axonometric, front and side elevations of a stair handrail with a rounded 67 mm wide by 41 mm tall profile glued to a post and fastened with a number 10 by 89 mm screw at 45 degrees.

Notes:

  1. Maximum permitted span is based on a slope between 35° and 45° from the horizontal.
  2. Minimum section modulus of top rail shall be 24,000 mm3, measured about the x-x axis.
  3. Pickets omitted on drawing, for clarity.
  4. Detail IC-1 or Detail IC-2, modified to suit a sloping application may be used for picket to rail connections.
Maximum Span of Rail, Measured Along the Slope
Maximum Span of Rail, Measured Along The Slope
Rail SpeciesMaximum Span, m (ft-in)
Oak, Maple4.30 (14'-1")
Column 12

Detail IG-1 — Interior Stair Guard Connection: Notched Post Glued & Screwed to Stringer & Riser

Detail IG-1 composite construction diagram. The first view shows plan and axonometric views of a newel post notched and glued to a stair stringer and riser, with the connection fastened using a number 10 by 50 mm countersunk screw. The second view shows front and side elevation diagrams of the stair stringer-to-post connection, with the newel post fastened to the stringer using three number 10 by 89 mm countersunk screws, and the stair tread labeled in the diagram.

Notes:

  1. Stringer shall be oak or maple.
  2. Notch post 38 mm x 60 mm (1½" x 2⅜") to fit over stair stringer.
  3. Only the first riser and tread are shown, for clarity.
  4. Minimum thickness of riser shall be 12 mm (1/2").
  5. Detail IC-1 or Detail IC-2, modified to suit a sloping application may be used for picket to rail connections.
  6. Dimensions shown are in mm unless otherwise specified.
Maximum Spacing Between Posts
Maximum Spacing Between Posts
Post SpeciesMaximum Span, m (ft-in)
Oak, Maple, Yellow Poplar, Hemlock, White Pine3.30 (10'-10")
Column 12

Detail IG-2 — Interior Stair Guard Connection: Post Glued and Screwed to Stringer

Multi-view construction diagram showing plan, axonometric, front elevation, and side elevation of a newel post glued in place to a stair stringer with a shoe, fastened with number 10 by 89 mm countersunk screws.

Notes:

  1. Stringer shall be oak or maple.
  2. Only the first riser and tread are shown, for clarity.
  3. Minimum thickness of riser shall be 12 mm (1/2").
  4. Detail IC-1 or Detail IC-2, modified to suit a sloping application may be used for picket to rail connections.
  5. Dimensions shown are in mm unless otherwise specified.
Maximum Spacing Between Posts
Maximum Spacing Between Posts
Post SpeciesMaximum Span, m (ft-in)
Oak, Maple, Yellow Poplar, Hemlock, White Pine3.30 (10'-10")
Column 12

Detail IG-3 — Interior Stair Guard Connection: Post Glued and Screwed to Stringer and Stud Wall

Multi-view construction diagram showing plan, axonometric, front elevation, and side elevation of a newel post glued to a stringer and wood stud wall, with gypsum board and specified screw fasteners at the base.

Notes:

  1. Minimum thickness of riser shall be 12 mm (½").
  2. Detail IC-1 or Detail IC-2, modified to suit a sloping application may be used for picket to rail connections.
  3. Dimensions shown are in mm unless otherwise specified.
Maximum Spacing Between Posts
Maximum Spacing Between Posts
Post SpeciesMaximum Span, m (ft-in)
Oak, Maple, Yellow Poplar, Hemlock, White Pine3.30 (10'-10")
Column 12

Detail IG-4 — Interior Stair Guard Connection: Oak or Maple Post and Picket Volute

Multi-view construction diagram showing plan, axonometric, front elevation, and side elevation of a volute newel post with pickets attached using dowels glued to the tread and secured with a screw connector and washer.

Notes:

  1. Maximum permitted span is measured from the centre of the volute to a post or other solid support.
  2. Other top rail systems may be used provided that the section modulus is not less than 24,000 mm3, measured about the vertical axis.
  3. Newel post and pickets in the volute shall be oak or maple. See Table 3.1.2. for minimum sizes of pickets.
  4. Detail IC-1 or Detail IC-2, modified to suit a sloping application may be used for picket to rail connections.
  5. Dimensions shown are in mm unless otherwise specified.
Maximum Span of Rail, Measured Along the Slope
Maximum Span of Rail, Measured Along The Slope
Post and Picket SpeciesMaximum Span, m (ft-in)
Oak, Maple4.30 (14'-1")
Column 12

Detail IG-5 — Interior Stair Guard Connection: Picket Volute, 260 mm (101/4") Wide

Detail IG-5 composite construction diagram. The first view shows plan and axonometric views of a corner stair landing with 45 mm square base pickets inserted into dowels that are glued in place through the tread. The second view is an elevation diagram of a stair guard railing, showing a continuous handrail connected to guard pickets at the landing and along the descending stair section. The third view is an elevation diagram of a stair guard at the landing-to-stair transition, showing pickets at the change in level and a guard rail that changes from vertical at the landing to an angled alignment following the stair stringer.

Notes:

  1. Maximum permitted span is measured from the centre of the volute to a post or other solid support.
  2. Other top rail systems may be used provided that the section modulus is not less than 24,000 mm3, measured about the vertical axis.
  3. See Table 3.1.2. for minimum sizes of pickets.
  4. Detail IC-1 or Detail IC-2, modified to suit a sloping application may be used for picket to rail connections.
  5. Dimensions shown are in mm unless otherwise specified.
Maximum Span of Rail
Maximum Span of Rail
Picket SpeciesMaximum Span, m (ft-in)
Yellow Poplar, Hemlock, White Pine1.80 (5'-11")
Column 12

Detail IG-6 — Interior Stair Guard Connection: Picket Volute, 240 mm (91/2") Wide

Multi-view construction diagram showing plan, axonometric, front elevation, and side elevation of a stair guard with 45 mm square pickets connected using dowels to the tread at landing and stair, with handrail at top and bottom rail.

Notes:

  1. Maximum permitted span is measured from the centre of the volute to a post or other solid support.
  2. Other top rail systems may be used provided that the section modulus is not less than 24,000 mm3, measured about the vertical axis.
  3. See Table 3.1.2. for minimum sizes of pickets.
  4. Detail IC-1 or Detail IC-2, modified to suit a sloping application may be used for picket to rail connections.
  5. Dimensions shown are in mm unless otherwise specified.
Maximum Span of Rail
Maximum Span of Rail
SpeciesMaximum Span, m (ft-in)
Yellow Poplar, Hemlock, White Pine1.80 (5'-11")
Column 12

Detail IH-1 — Interior Stair Guard Connection: Cantilevered Picket Screwed to Stair Stringer

Multi-view construction diagram showing plan, axonometric, front elevation, and side elevation of a stair guard assembly with pickets fastened to a 45 by 255 mm stringer and 45 by 138 mm top rail using countersunk screws.

Notes:

  1. Stair stringer shall be oak or maple.
  2. Provide a suitable post, return, or solid support at each end of the guard.
  3. See Table 3.1.2. for minimum sizes of pickets.
  4. Dimensions shown are in mm unless otherwise specified.

Appendix A

Explanatory Material for SB-7

Appendix A to this Supplementary Standard is included for explanatory purposes only and does not form part of the requirements. The bold-faced reference numbers that introduce each item apply to the requirements in this Supplementary Standard.

A-1.1.1 Scope. A guard constructed in conformance with this Supplementary Standard is deemed to satisfy the requirements of Sentence 9.8.8.2.(6) of Division B.

Guard design in this Supplementary Standard is based on a height of 1,070 mm and a maximum clear spacing of 100 mm between pickets or balusters.

A-1.1.1.(2) Guards located on the exterior of a building are subject to deterioration as a result of hygrothermal, electrochemical or biochemical action.

A-1.2.1 Cantilever Action.Where guards incorporate wood posts that are continuous from the top of the guard to the ground, or where the tops of the posts are attached to a superstructure that is connected to the building, the cantilever assumption in the Supplementary Standards is no longer valid. An example of a continuous post is shown in Figure A-1.2.1.

Figure A-1.2.1. Typical Continuous Post

Side elevation diagram of an 89 by 89 mm wood guard post running continuously from the top of a footing below grade through the deck level to the top of the guard, with the deck and grade levels labeled.

A-1.2.2. Classification. A Post and Rail System consists of a top rail that transfers horizontal loads to posts. The posts transfer the loads from the rail to the floor system. This system may incorporate a bottom rail that is anchored at each end to the posts. Infill panels or infill pickets are installed between the top rail and the floor or bottom rail. Examples of Post and Rail Systems are shown in Figure A-1.2.2.A.

The term “infill pickets” refers to an assembly of vertically oriented elements that span between the floor or bottom rail and the top rail. For the purpose of this Supplementary Standard, the words “picket” and “baluster” both relate to these individual elements.

The spacing of the posts in a Post and Rail System is detailed in this Supplementary Standard and is dictated by the ability of the posts to accept the design loads. The maximum spanning capacity of the rails is often not realised because it is dictated by the post spacing.

A Cantilevered Picket System consists of a top rail that transfers horizontal loads to pickets. The pickets transfer the loads from the top rail to the floor system. An example of a Cantilevered Picket System is shown in Figure A-1.2.2.B.

A guard classified as a Post and Rail System or a Cantilevered Picket System need not always terminate at a post if:

  1. the top rail is connected adequately to an element capable if accepting the forces applied to it, or
  2. the guard changes direction and the rails are adequately fastened at the return.

Figure A-1.2.2.A Typical Post and Rail Systems — Figure A-1.2.2.B Cantilevered Picket System

Three-view illustration showing two guard configurations — top rail only and top and bottom rail — on a sloped site, alongside a larger 3D perspective view of a guard with vertical pickets, top cap rail, and bottom rail on a slope.

A-2.1.1 Lumber Grades. Whereas Northern Species is specified as the minimum lumber grade, Spruce-Pine-Fir, Douglas Fir-Larch and Hem-Fir may also be used since their structural properties exceed those of Northern Species. Cedar falls within the classification of Northern Species Group.

A-2.1.3 Floor Construction. The lateral loads acting on a guard are transferred from either the posts or the pickets to the floor system. Therefore, the floor system must be sufficiently strong to transfer these loads.

A-2.1.4 Connectors. Pre-drilling of wood elements may be required in order to avoid splitting of structural wood elements. Where a glued joint is required, an adhesive conforming to CSA Standard O112.4-M1977 (Polyvinyl Adhesives for Wood) and CSA Standard O112.8-M1977 (Polyvinyl Adhesives - Cross Linking, for Wood) is acceptable.

A-2.1.5 Decay-Resistant Lumber. Cedar is a species considered resistant to decay.