Materials specification
for plywood bracing
Plywood bracing panels
must comply with the requirements of AS/NZS2269-1994
Plywood - Structural and be branded with the PAA /
JAS-ANZ Product Certification brand stamp.
The minimum grade
specification for plywood bracing panels is DD grade. The
stress grade must be clearly marked on each plywood
panel. Standard plywood bracing panel lengths are 2440mm,
2700mm and 2745mm to suit standard ceiling heights of
2400mm and 2700mm. Standard widths are 900mm and 1200mm
to suit standard stud spacings.
To generate the design
racking resistances, the hand and power driven fasteners
specified in Table 1 must be used to connect the
structural plywood to the frame. Fastener spacings are
shown in table 2.
Reference: Plywood
Association of Australia "Structural plywood wall
bracing design manual -1992 revision"
Table 1: Fastener
Specification
| Hand
Driven Nails |
Power
Driven Nails |
*Power Driven Staples |
| 2.8-3.15mm
Diameter Structural Clouts or Flathead Nails x
30mm long |
Senco
Nail EC18 (2.33 dia. x 38 Flathead) |
Senco Staple N17 |
| |
Bostitch
Nail C5D250 or AC5D250 (2.5 dia. x 45 Flathead) |
Bostitch Staple NCS4-123 |
| |
Bostitch
Nail CR3d (3.06 dia. x 32 Flathead) |
Jambro Staple A10617 |
| |
Jambro
RBC B20998 (2.8dia. x32 Barbed Coil Nail) |
|
| |
Duo-Fast
C25/50 (2.5 dia. x 50) |
|
| *Reduced
fastener spacings only |
NOTES:
- Fasteners with
equivalent dimension i.e. head size and shape,
shank diameter and length, to those in Table 1
are deemed acceptable.
- All fasteners are to
be galvanised or suitably coated.
- If smaller diameter
hand driven nails are used, the spacings of nails
can be reduced in the ratio of the basic lateral
loads per nail for J4 or JD4 joint group given in
Table 4.1 of AS1720.1 Timber Structures Code.
This is for the lower nail diameter relative to
the tabulated load for a 2.8mm diameter nail.
TABLE 2: Fastener Spacing
(mm)
| |
Nails |
Staples |
| |
Type A Bracing Unit
|
Type B Bracing Unit
|
Type A Bracing Unit
|
Type B Bracing Unit
|
| Framing |
| Top and
Bottom Plates |
150 |
50 |
100 |
35 |
| Any
Horizontal Butt Joints |
150 |
50 |
100 |
35 |
| All
Vertical Edges |
150 |
150 |
100 |
100 |
| Intermediate
Studs |
300 |
300 |
200 |
200 |
NOTES
- Refer to Table 1 for
approved fasteners
- No nogging required
except at horizontal plywood butt joints
- Nails to be a minimum
of 7mm from panel edges
- Panel edges shall be
supported by studs, noggings or plates
- The fastener spacings
in Table 2 specified for staples also apply to
the Duo Fast fastener C/25/50
- Type A and B bracing
units are described in the article: "Plywood
wind bracing – standard solutions".
|
