MUNICODE SERVICES LTD.

The Preserved
Wood Foundation
Guide

Prepared by MuniCode Services Ltd.

Outline and Restrictions of this Guide

• The following information required for the construction of Preserved Wood Foundations
(PWF's) is based on CAN/CSA S406-M92, "Construction of Preserved Wood Foundations".

• This standard is required by the 1995 National Building Code of Canada as adopted and amended
by The Uniform Building and Accessibility Standards Regulations.

• The standard applies to all PWF's for dwellings which fall under Part 9 of the 1995 NBC.

• The standard as well as this guide is based on specific design assumptions. If any of the design
conditions are different from these assumptions, or if the local authority specifically requires it, the
PWF must be designed by a professional engineer.

• The foundation builder shall procure a copy of the standard and build in accordance to it. If there
are any discrepancies between this guide and the Canadian Standard, the standard shall be
considered correct.

• The CAN/CSA S406-M92 is available from Canadian Standards Association, 178 Rexdale
Blvd., Rexdale, ON, M9W 1R3, Phone: 416-747-4000.

• This guide is based on requirements for basement concrete slabs and wood sleeper floors only.
Additional and/or alternative codes are required for suspended wood floors in basements.

1
Terms Used in this Guide

• End Wall - the exterior walls that are

parallel to the floor joists, they do not SIDEWALL
PERPINDICULAR TO FLOOR JOISTS
support the floor joists.

• Side Wall - the exterior walls that are ENDWALL

perpendicular to the floor joists. PARALLEL TO
FLOOR JOISTS

FLOOR JOISTS
• Framing Strap - a strip of 0.9mm (20
gauge) galvanized metal at least 38mm x 400mm (1 1/2" x 16") in size. Framing straps are
generally used to transfer lateral loads into wall studs at floor joist locations or at openings in the
exterior wall.

• Granular Drainage Layer - the continuous layer of crushed stone or rock used to drain moisture
away from the bottom of the foundation. It may also distribute loads from the
footing to undisturbed soil.

• Jack Stud - a stud that is less than full height and is fastened to a full height stud to support the
ends of lintels or beams at foundation wall openings. It will transfer the vertical
loads supported by the lintel or beam to the footing.

• Knee Wall - a less than full height foundation wall used adjacent to the main foundation wall to
support additional loads from brick or stone siding or attached concrete slabs
(garage).

2
Materials

• All lumber and plywood used in a Preserved Wood Foundation must be treated with a
preservative, except in limited locations outlined by the standard.
CCA (or ACA)-
(name of inspection agency)
type of preservatice used
• Preserved wood will be identified as such by a

Company Name
CSA 0322 CCA 0092 First two digits identify the

and Logo
certification mark stamped on the material, stating treating plant, the last
conformance with CSA 0322 Standard. PWF - FBT two the year of treatment
TRAITE PAR USINE QUALIFIE ACNOR
FONDATIONS EN BOIS TRAITE

• Treated lumber shall not be...

• Cut lengthwise
• Notched Use approved for the material

Standard CSA 0322,

• Studs, blocking, and floor joists shall not be... under which material is qualified

• Cut
• Notched
• Bored
...to accommodate electrical, mechanical utilities, or any other reason.

• Foundation wall studs may be cut to length and installed with treated (uncut) end down.

• Where necessary to field cut treated lumber, the cuts must be treated with two applications of a
copper napathane preservative solution containing a minimum of 2% copper metal and prepared
with a solvent conforming to CSA Standard CAN/CSA-080.201.

• Nails for fastening treated material shall be hot-dipped galvanized or steel

• Staples shall be stainless steel with a minimum diameter or thickness of 1.6mm and a 9.5mm
crown.

• Framing anchors and straps shall be galvanized.

• Moisture and vapour barriers must be a minimum 0.15mm (6mil) thick and conform to
CAN/CGSB-51.34-M,"Vapour Barrier, Polyethylene Sheet for use in Building
Construction".
Tip: Look for a maple leaf with a check mark through it stamped on
your moisture or vapour barrier to ensure it has been tested and
complies with CGSB standards.

• Granular material for use in the granular drainage layer must be clean crushed stone or gravel that
passes through a 40mm sieve with not more than 10% of fine material that will pass through a
4mm sieve.

3
Site Preparation

• Excavation requirements shall conform to those of the appropriate building code.

See Section 9.12. of the 1995 National Building Code.

• All top soil and vegetation matter that would be under the building must be removed.

• The bottom of the excavation must be free of all organic material and standing water.

• The excavation depth must be determined in accordance to Section 9.12. of the 1995 NBC.

• A continuous drainage layer shall be installed under floors of PWF's and be not less than
125mm (5").

• The excavation and drainage layer shall drain to a sump, which shall be provided with positive
drainage, by gravity or pump, to a final disposal point outside the building.

• Perimeter drainage tile or pipe shall not be used with PWF's.

Footings
GRAVEL
BACKFILL
• Concrete footings shall be 19mm x
SCREED
76mm PWF
BOARD
placed on undisturbed soil or
on 125mm (5") granular GROUND VAPOUR
BARRIER
CRUSHED
drainage layer. ROCK

300mm
CRUSHED
BEYOND
• When concrete footings are ROCK
FOOTING
125mm MIN.
placed on undisturbed soil,
drainage shall be provided by CONCRETE
casting 60mm (2-1/4") dia. FOOTING
TO FINAL
water passages (pipes) @ 60Ø mm DRAIN DISPOSAL
PIPE @ 1200mm POINT
1200mm (4') o.c. in the (4') o.c.

footing.

Remember: No drainage tile or pipe with a PWF.

Foundation Columns

• Columns supporting floor beams shall be constructed in conformance with appropriate building
code.

4
Exterior Walls

Studs

• Stud sizes shall be dictated by backfill height conforming to the Stud Table (for 8' long studs
only) in the Appendix.

Wall Openings

• Where backfill height is 1200mm (4') or

less, framing and fastening around wall
3" NAILS @ 150mm (6") o.c.
FOR EACH LINTEL MEMBER
openings may conform to the appropriate
building code.
FRAMING STRAPS

LINTEL
• Where the height of backfill is greater than
1200mm (4'), the framing and fastening shall
JACK STUDS
conform to the following:
JOIST HANGERS
SILL PLATES 1) Lintels located below the wall top plate
shall be nailed to adjacent studs with
• 6 - 3" nails when the lintel is 140mm (2x6)
deep and...
• 8 - 3" nails where the lintel is 184mm (2x8)
deep.

BOTTOM PLATE 2) Each lintel member shall be fastened to the

CRIPPLE STUD
wall top plate with 3" nails spaced @ 150mm
3" NAILS - 2 ROWS AT 12" O.C.
(6") o.c.
CONCRETE FOOTING

WINDOW OPENING DETAIL

3) Jack studs and adjacent wall studs shall be
fastened together with by 2 rows of 3" nails
spaced @ 300mm (12") o.c.

4) Framing straps or framing anchors shall be provided at the connection between the sills, jack
studs, and cripple studs.

5) Cripple studs shall be the same size and spacing as specified for all wall studs.

6) For openings of 1200mm (4") or less, there shall be at least 2 studs on each side of the opening
when supporting a lintel and only one shall be a jack stud.

7) For openings between 1200mm (4') and 2400mm (8'), stud sizes and quantities shall conform
to the Window Opening Framing Table in the Appendix. Only one stud on each side shall be a
jack stud.

8) Nail laminated wood sills shall conform to the Window Opening Framing Table in the
Appendix.

5
9) Openings greater than 2400mm (8') shall be designed in conformance with Part 4 of the 1995
NBC (Professional Engineer’s design required).

Sheathing

• Wall sheathing thickness shall conform to the Plywood Sheathing Requirements Table in the
Appendix.

• All below grade edges shall be supported by framing members (studs), 2x4 blocking, or by
bottom wall plates.

• Edges shall be embedded in a sealant.

• A 2mm to 3mm separation shall be maintained between adjacent sheets of plywood.

• These gaps occurring below grade shall be sealed.

• Nailing shall conform to the minimum requirements of the “Minimum Fastening Requirements”
table in the Appendix.

• If the backfill height is non-uniform, nailing shall conform to Tables B8 to B5 for the walls that
are perpendicular to the opposing walls.

• Where backfill height is uniform, staples my be used in conformance to “Minimum Fastening

Requirements” table.

Concrete Slab Floors

• Concrete slab floors shall be not less than 75mm (3") thick exclusive of concrete topping.

• Slabs shall extend at least 25mm (1")

above the top of the bottom plate.
GRAVEL
• A poly ground cover shall be placed BACKFILL
between the floor slab and the granular
drainage layer. 125mm (5") min. CRUSHED ROCK
0.15mm (6mil) VAPOUR BARRIER
75mm (3") min. CONCRETE SLAB
• All joints in the poly ground cover shall 300mm
be overlapped a minimum of 300mm (12") BEYOND
CRUSHED
and the sheet shall be sealed to the FOOTING
ROCK

foundation wall footing around its

perimeter.

• All penetrations of the floor by pipes or other objects shall be sealed against water vapour and soil
gas leakage.
Note: Crawl spaces (no concrete slab) shall be backfilled and compacted to 2/5 of the exterior
backfill height for lateral support and lined with a poly ground cover.

6
First Floors

• The first floor system is an integral part of the entire foundation.

• Floors at the top of foundations shall be constructed to prevent the inward movement of exterior
walls due to lateral pressure.

* A PWF shall never be backfilled before the entire first floor system (joists, subfloor, etc.) and
basement floor are completely installed.

• Joists and blocking shall be nailed as required by the Minimum Fastening Requirements Table.

FIRST FLOOR
EXTERIOR WALL
Support for Side Walls

• When the backfill height is greater than 1500mm (5'),

framing straps shall be installed to each stud to attach
FLOOR JOIST
the floor to the foundation wall in accordance with the
requirements of the Minimum Fastening Requirements
FRAMING STRAP
w/3 - 3" nails Table.

• Top chord bearing Trusses or I-joists shall be

connected to the top of the wall to prevent inward
movement of the wall by means of:
SIDE WALL SUPPORT DETAIL
1) framing straps nailed to the ends of the top chord
and the inner face of the wall studs;
2) steel hangers or a wood ledger located to provide
FIRST FLOOR
EXTERIOR WALL positive bearing of the top chord against the wall stud
END WALL SOLID
BLOCKING ends or other means of providing support.
38mm x 89mm (2x4)
NAILER • Bottom chord bearing Trusses or I-joists shall be
1ST JOIST connected to the top of the wall to prevent inward
FRAMING STRAP
movement of the wall by means of:
W/ 3" NAILS
1) steel hangers or a wood ledger located as to provide
positive bearing of the chord end against the wall studs
or other means of providing support.

END WALL SUPPORT DETAIL Support for End Walls

• Full-depth blocking shall be installed, in line with foundation studs, between the rim joist or wall
studs and the first joist from the wall.

• When backfill height is greater than 1500mm (5'), the

first joist in from the end walls shall have a nailer joist (at least 2x4) fastened to it, mounted flush
to the top of the joist.

• The subfloor shall be nailed to both the full joist and the nailer joist with one row of 2" nails at

7
100mm (4") o.c. Framing straps shall also be installed in accordance with the Minimum Fastening
Requirements Table in the Appendix.

• When Trusses or I-joists top chords are located at the level of the foundation top plates, blocking
shall be installed to ensure the direct transfer of lateral loads from studs to the top chord of the first
joist and:
1) Increased nailing of the subfloor to the top chord is also required in accordance to the Minimum
Fastening Requirements Table. If the top chord of the joist is a minimum 89mm (4") wide, the
additional (2x4) nailer joist is not required.

• When Trusses or I-joists bottom chords are located at the level of the foundation top plates, lateral
inward movement of the wall shall be resisted by means of:
1) blocking installed to ensure the direct transfer of lateral loads from the end wall studs upward
into the floor sheathing at a top chord located at a distance from the wall at least twice the depth of
the joist (may require blocking between the first two joists); or
2) If the backfill height is uniform on opposite end walls, install blocking in a continuous line
between all the joists to transfer the lateral loads across the entire foundation.

Non-Uniform Backfill Heights

• When the backfill heights are at different heights around the house, additional nailing
requirements must be incorporated for the foundation wall sheathing. These requirements may be
found in the “Perimeter Nailing Requirements for Differential Backfill Heights” table in the
appendix at the back of this manual.

8
 Stairwell Openings

• When openings are greater than 1200mm (4') from a side wall and 1800mm (6') from an
endwall, stairwell opening construction shall conform to the minimum requirements for wood
frame construction in the appropriate building code.

• When openings are closer to their adjacent walls than specified previously, they shall conform to
the following:

1) The maximum dimension of a stairwell opening shall be 4300mm (14').

2) Openings less than 1200mm (4')

MULTY-PLY HORIZONTAL BEAM
from a side wall shall be framed with
HEADER
a multi-ply horizontal member.
TRIMMERS
SEE TABLE

BLOCKING
REQ'D IF BACKFILL HEIGHT

>1500mm (5')

STAIRWELL PERPINDICULAR TO SIDE WALL

MULTY-PLY HORIZONTAL BEAM

HEADERS
3) Openings less than 1800mm (6')
SEE TABLE from an endwall shall be framed
with a multi-ply horizontal member.
BLOCKING

4) The size and nailing requirements

of these multi-ply members for each
circumstance shall conform to the
“Stairwell Opening Framing” table
BLOCKING
in the appendix at the back of this
REQ'D IF BACKFILL HEIGHT
>1500mm (5') manual.

STAIRWELL PARALLEL TO END WALL

9
 Support of Masonry Veneer and Concrete Slabs

• Masonry veneer cladding shall be installed according to appropriate building code and shall be
supported on either...
i) a knee wall attached to the exterior of the main
foundation wall.
ii) top of the main foundation wall.

Supported on Knee Wall

• Footings supporting both a foundation wall and a knee wall shall conform to the appropriate
building code to accommodate the additional width required by the knee wall.

• Knee wall studs shall be a minimum 2x4 @ 400mm (16") o.c. for supporting a single wythe of
masonry to a maximum height of 550mm
(18').
BRICK TIE
TYPICAL WOOD FRAME WALL

• The knee wall shall be installed outside

the exterior moisture barrier and nailed at
the top of each stud to the main
foundation wall.
FLASHING
FINISH GRADE
MINIMUM 300mm x 12mm
TREATED PLYWOOD
• If the knee wall exceeds 1500mm (5') in
height, the studs shall also be toe-nailed
TREATED WALL STUD
at mid-height to the wall.

• Top plates of knee walls shall be

GENERAL NOTES:
doubled to support the masonry veneer.
1. KNEE-WALL SHEATHING SHALL GRAVEL BACKFILL
EXTEND TO AT LEAST 300mm
BELOW GRADE KNEE WALL TREATED STUDS
2. BACKFILL MAY OCCUPY SPACE
BETWEEN KNEE-WALL STUDS.
• Joints in the top plates shall be placed a
3. MAIN FOUNDATION WALL MOISTURE
BARRIER SHALL BE CONTINUOUS
19mm x 76mm PWF
SCREED BOARD minimum of two stud spaces apart and
BETWEEN EXTERIOR WALL SHEATHING
AND KNEE WALL FRAMING.
CONCRETE FLOOR
shall occur directly above the centre of a
4. MOISTURE BARRIER SHALL NOT
EXTEND UNDER THE CONC. FOOTING
OR BETWEEN THE GRANULAR
GROUND VAPOUR BARRIER
CRUSHED ROCK
stud.
DRAINAGE LAYER AND THE BACKFILL.

300mm CRUSHED ROCK

BEYOND FOOTING
• Knee wall sheathing shall extend a
125 mm minimum of 300mm (12") below grade at
any point.
CONCRETE FOOTING
50Ø mm DRAIN PIPE
4" O/C THROUGH
FOOTINGS
• No exterior moisture barrier is required
BRICK VANEER SUPPORTED ON KNEE WALL over the knee wall sheathing.

Supported on Main Foundation Wall

• Where masonry veneer is supported on the main foundation wall, the foundation framing shall
have a width sufficient to provide required support for the masonry veneer as well as
accommodating the floor framing.

10
• Top plates shall be doubled and pressure treated.
Exterior Concrete Slabs

• Where driveway or garage floor slabs are

butted against foundation walls, one of the
following two steps shall be taken to support
additional load:
i) Design the stud size and spacing as if
the backfill height were 500mm (20") CONCRETE SLAB
higher than the actual height. ON GRADE

REINFORCING STEEL
ii) Reinforce the slab and support it on a
preserved wood knee wall (as described
above).
MINIMUM 300mm x 12mm
TREATED PLYWOOD

Garage Frost Walls

• Frost walls used to support garage walls shall

be placed in a trench and backfilled on both
GARAGE SLAB SUPPORTED ON KNEE WALL
sides.

• Footings shall be placed below frost penetration level.

Note: Properly insulating the frost wall may reduce the required footing depth.

• Where the frost wall is subject to balanced soil loads, studs may be 2x4 with 1/2" plywood
sheathing extending a minimum of 24" below grade.

Exterior Moisture Barrier

• The below grade portion of the exterior face of the wall sheathing on a preserved wood
foundation enclosing living space shall be protected by a moisture barrier.

• A polyethylene sheet moisture barrier shall be applied to the wall sheathing by embedding it into
vertical beads of sealant, or into damproofing applied uniformly over the sheathing.

• Joints between poly sheets shall be vertical, lapped a minimum of 600mm (2') and sealed.

• When attached with vertical sealant beads, the poly shall not be sealed along the bottom of the
wall.

• The upper edge of the poly ground sheet shall be looped a minimum of 150mm (6") and secured
in place by the nailing of a cover plate.

• The cover plate shall be a pressure treated strip of plywood having a minimum thickness of
12.5mm and a minimum width of 300mm (12").

11
• The top edge of this continuous strip shall be embedded in sealant or damproofing along it's full
length.

• The plywood strip may follow the contour of the finished outside grade but shall extend a
minimum of 75mm (3") above grade at all points.

• The moisture barrier shall be protected at interior and exterior corners from mechanical damage
with treated plywood strips or other durable corner construction.

• The moisture barrier shall cover the entire surface below grade and extend to the bottom edge of a
wood footing. For a concrete footing, it shall not obstruct the required drainage passages.

Backfilling

• PWF's shall not be backfilled until the basement floor and the floor on top of the foundation are
completely installed.

• Heavy equipment and loads shall be kept a safe distance from foundations.

• Backfill shall be placed in uniform lifts not exceeding 600mm (2') around the foundation.

• The site shall be graded according to appropriate building codes.

• Backfill material shall have good drainage characteristics. All backfill material placed within
600mm (2’) of the foundation wall shall be free of deleterious debris, frozen clumps, and boulders
larger than 150mm (6”) in diameter.

12
Appendix
Tables

13
 Plywood Sheating Requirements

Permissible Backfill Heights, mm (ft-in)

Plywood Stud Plywood Thickness

Alignment Spacing
on Wall mm (in) 12.5mm 15.5mm 18.5mm

Face grain 300 (12) 2900 (9'-6") 3500 (11'-6") 3600 (11'-10")
perpindicular to studs 400 (16) 2200 (7'-3") 2600 (8'-6") 3600 (11'-10")
- - - - - - - - - - - - - - - - - - - -- - - - - - - - - - - -------------- - - - - - - -------------- - - - - -------------- - -
Face grain 300 (12) 2100 (6'-11") 2700 (8'-10") 3000 (9'-10")
parallel to studs 400 (16) 1300 (4'-3") 2000 (6'-7") 2200 (7'-3")

Note: Plywood is required to have at least 4 plies (4 ply plywood shall be installed with grain perpindicular to studs)
 Minimum Fastening Requirements

Minimum Minimum no. or

Length of nails max. spacing
Construction Detail mm (in) of fasteners
Foundation Bottom wall plate to wood footing plate 76 (3) 600mm (24) centres
wall framing
(nails) Bottom wall plate to stud (end nail) 76 (3) 2 each stud
(toe nail) 63 (2 1/2) 3 each stud

Top wall plate to stud (end nail)

-38x89mm (2x4) stud 89 (3 1/2) 2 each stud
-38x140mm (2x6) stud 89 (3 1/2) 3 each stud
-38x184mm (2x8) stud 89 (3 1/2) 4 each stud

Plate to plate nailing for doubled top plates

-38x89mm (2x4) stud 76 (3) 2 each stud space
-38x140mm (2x6) stud 76 (3) 2 each stud space
-38x184mm (2x8) stud 76 (3) 3 each stud space

Horizontal wall blocking to wall stud 76 (3) 2 each end of block

Floor framing End wall blocking to floor joists 76 (3) 400mm (16") centres
(nails)
Full depth end wall blocking to 76 (3) 2 each end of block
floor joists (end nail)

Ledger strip to wall stud 89 (3 1/2) 3 each stud

Floor attachment Floor joists and blocking at top of

to foundation foundation wall to top plate (toe nail)
wall (nails and -38x89mm (2x4) wall plate 89 (3 1/2) 2 per joist or block
framing straps) -38x140mm (2x6) wall plate 89 (3 1/2) 3 per joist or block
-38x184mm (2x8) wall plate 89 (3 1/2) 4 per joist or block

In addition, framing straps are required 76 (3) 1 framing strap at

where backfill height exceeds every stud, with 3 nails
a) 1500mm (5') with sleeper or slab floor, or into floor header and 3
b) 2000mm (6'-6") with suspended wood floor nails into inner face of
foundation wall stud
Wall sheathing Sheathing to wall framing (uniform backfill)
and subfloor and subfloor to floor joists
(nails or staples) -Nails 51 (2) 150mm (6") centres along
edges and 300mm (12")
centres along intermediate
supports

-Staples 51 (2) 100mm (4") centres along

edges and 200mm (8")
centres along intermediate
supports

Framing around In addition to normal nailing requirements,

windows framing anchors are required where backfill
(framing anchors) height exceeds
a) 1200mm (4') with sleeper or slab floor;
or
b) 2000mm (6'-6") with suspended wood
floor, at sill plate to
-cripple studs 51 (2) 1 framing anchor at each
-jack studs point, nailed as required by
manufacturer
 Stud Table (8' Stud length)

Stud size, mm x mm - 2.4m (8') studs

Maximum buillding
width (parallel to 38 x 89 38 x 140 38 x 184
floor joists) Lumber
Stud spacing - mm (in), o.c.
With center No center Strength
support support grouping Grade 400 (16) 300 (12) 400 (16) 300 (12) 400 (16) 300 (12)

Maximum backfill when supporting 1 storey above foundation,

1 Storey no brick veneer, mm

7m 5m Species 1 SS 1200 1350 2075 2400 2400 2400

(23 ft) (16 ft) No.2 1050 1250 1650 1925 2050 2400
Species 2 SS 1025 1200 1700 1975 2125 2400
No.2 875 1075 1450 1675 1800 2075
--------------------- --------------------- --------------------- --------------------- --------------------- --------------------- --------------------- --------------------- --------------------- ---------------------
10m 8m Species 1 SS 1200 1350 2025 2400 2400 2400
(33 ft) (26 ft) No.2 925 1150 1600 1875 2025 2375
Species 2 SS 925 150 1650 1925 2075 2400
No.2 750 975 1400 1650 1750 2050

Maximum backfill when supporting two storeys above foundation,

2 Storey no brick veneer, mm

7m 5m Species 1 SS 1200 1350 2050 2400 2400 2400

(23 ft) (16 ft) No.2 950 1175 1625 1900 2025 2375
Species 2 SS 950 1175 1650 1950 2075 2400
No.2 775 975 1400 1650 1750 2050
--------------------- --------------------- --------------------- --------------------- --------------------- --------------------- --------------------- --------------------- --------------------- ---------------------
10m 8m Species 1 SS 1075 1350 1950 2350 2400 2400
(33 ft) (26 ft) No.2 800 1050 1550 1825 1975 2325
Species 2 SS 775 1050 1575 1875 2025 2400
No.2 575 850 1350 1575 1700 2000
 Maximum backfill when supporting one storey above foundation,
1 Storey (w/ brick veneer) with brick veneer, mm

10m 8m Species 1 SS n/a n/a 1975 2375 2400 2400

(33 ft) (26 ft) No.2 n/a n/a 1575 1850 1975 2350
Species 2 SS n/a n/a 1600 1900 2050 2400
No.2 n/a n/a 1350 1600 1725 2025

Maximum backfill when supporting two storeys above foundation,

2 Storeys (w/ brick veneer on first storey) with brick veneer on first storey, mm

10m 8m Species 1 SS n/a n/a 1900 2300 2400 2400

(33 ft) (26 ft) No.2 n/a n/a 1500 1800 1925 2300
Species 2 SS n/a n/a 1525 1825 2000 2375
No.2 n/a n/a 1300 1550 1675 1975

Maximum backfill when supporting two storeys above foundation,

2 Storeys (w/ brick veneer full height) with brick veneer full height, mm

10m 8m Species 1 SS n/a n/a 1875 2250 2400 2400

(33 ft) (26 ft) No.2 n/a n/a 1450 1750 1900 2250
Species 2 SS n/a n/a 1500 1800 1950 2325
No.2 n/a n/a 1250 1500 1625 1950

Note: When brick veneer supported on knee wall, the sections headed "no brick veneer" shall apply.
 Foundation Wall Sheathing
Perimeter Nailing Requirements for Differential Backfill Heights

(plan view) Conversions:

L
150mm - 6"
100mm - 4"
65mm - 2 1/2"
W
50mm - 2"

Nails:
51 - 2"
63 - 2 1/2"
Preserved wood 76 - 3"
Backfill 'A' foundation wall

(elevation) Backfill 'B'

Notes: All panel edges are backed with 38mm (2") or wider framing (studs or blocking)
Nail spacing along intermediate framing members is 300mm (12").

Table B8 - Backfill 'A' = 2.4m (8 ft)

Required nail spacing along sheathing panel edges, mm

Common
Backfill 'B' nail L/W
m (ft) length, mm 0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8 2.0
<=0.6 (2) 51 150 100 65 50 - - - - -
>0.6 (2) 51 150 100 65 65 - - - - -
>1.2 (4) 51 150 100 65 65 50 - - - -
>1.5 (5) 51 150 100 100 65 65 50 - - -
>1.8 (6) 51 150 150 150 150 150 150 150 150 150
- - - - - - - - - - - - ------------ ------ ------------------- - -------- - -------- - -------- - -------- - -------- - -------- - -------- -
<=0.6 (2) 63 150 150 100 65 65 65 - - -
>0.6 (2) 63 150 150 100 65 65 65 50 - -
>1.2 (4) 63 150 150 100 100 65 65 65 50 -
>1.5 (5) 63 150 150 150 100 100 65 65 65 50
>1.8 (6) 63 150 150 150 150 150 150 150 150 150
- - - - - - - - - - - - ------------ ------ ------------------- - -------- - -------- - -------- - -------- - -------- - -------- - -------- -
<=0.6 (2) 76 150 150 100 100 65 65 65 50 -
>0.6 (2) 76 150 150 150 100 65 65 65 50 50
>1.2 (4) 76 150 150 150 100 100 65 65 65 50
>1.5 (5) 76 150 150 150 150 100 100 65 65 65
>1.8 (6) 76 150 150 150 150 150 150 150 150 150
Table B7 - Backfill 'A' = 2.1m (7 ft)

Required nail spacing along sheathing panel edges, mm

Common
Backfill 'B' nail L/W
m (ft) length, mm 1.0 1.4 1.6 1.8 2.0 2.4 2.6 2.8 3.0
<=0.6 (2) 51 65 65 50 - - - - - -
>0.6 (2) 51 100 65 50 - - - - - -
>1.2 (4) 51 100 65 65 65 50 - - - -
>1.5 (5) 51 150 150 150 150 150 150 150 150 150
- - - - - - - - - - - - ------------ ------ ------------------- - -------- - -------- - -------- - -------- - -------- - -------- - -------- -
<=0.6 (2) 63 100 65 65 65 65 - - - -
>0.6 (2) 63 100 100 65 65 65 50 - - -
>1.2 (4) 63 150 100 100 65 65 65 50 50 -
>1.5 (5) 63 150 150 150 150 150 150 150 150 150
- - - - - - - - - - - - ------------ ------ ------------------- - -------- - -------- - -------- - -------- - -------- - -------- - -------- -
<=0.6 (2) 76 150 100 100 65 65 65 50 50 -
>0.6 (2) 76 150 100 100 100 65 65 65 50 50
>1.2 (4) 76 150 150 100 100 100 65 65 65 65
>1.5 (5) 76 150 150 150 150 150 150 150 150 150

Table B6 - Backfill 'A' = 1.8m (6 ft)

Required nail spacing along sheathing panel edges, mm

Common
Backfill 'B' nail L/W
m (ft) length, mm 1.0 1.4 1.6 1.8 2.0 2.5 3.0 3.5 4.0
<=0.9 (3) 51 150 100 65 65 65 50 - - -
>0.9 (3) 51 150 100 100 100 65 65 50 - -
> 1.2 (4) 51 150 150 150 150 150 150 150 150 150
- - - - - - - - - - - - ------------ ------ ------------------- - -------- - -------- - -------- - -------- - -------- - -------- - -------- -
<=0.9 (3) 63 150 150 100 100 100 65 65 50 -
>0.9 (3) 63 150 150 150 100 100 100 65 65 50
> 1.2 (4) 63 150 150 150 150 150 150 150 150 150
- - - - - - - - - - - - ------------ ------ ------------------- - -------- - -------- - -------- - -------- - -------- - -------- - -------- -
<=0.9 (3) 76 150 150 150 150 100 100 65 65 65
>0.9 (3) 76 150 150 150 150 150 100 100 65 65
> 1.2 (4) 76 150 150 150 150 150 150 150 150 150
Table B5 - Backfill 'A' = 1.5m (5 ft)

Required nail spacing along sheathing panel edges, mm

Common
Backfill 'B' nail L/W
m (ft) length, mm 1.0 1.2 1.4 1.6 2.0 2.5 3.0 3.5 4.0
<=0.9 (3) 51 150 150 150 150 100 100 65 65 65
>0.9 (3) 51 150 150 150 150 150 150 150 150 150
- - - - - - - - - - - - ------------ ------ ------------------- - -------- - -------- - -------- - -------- - -------- - -------- - -------- -
<=0.9 (3) 63 150 150 150 150 150 150 150 100 65
>0.9 (3) 63 150 150 150 150 150 150 150 100 100
- - - - - - - - - - - - ------------ ------ ------------------- - -------- - -------- - -------- - -------- - -------- - -------- - -------- -
<=0.9 (3) 76 150 150 150 150 150 150 150 100 100
>0.9 (3) 76 150 150 150 150 150 150 150 150 150