FLOOR INSTALLATION DETAILS - RESIDENTIAL CANADA - PKI 10, 20, 35 plus, 40 & 50
WEB HOLE SPECIFICATIONS
TYPICAL PERFORMANCE RATED I-JOIST FLOOR FRAMING AND CONSTRUCTION Some framing requirements
such as erection bracing and
blocking panels have been
omitted for clarity.
1g
1d
Load bearing wall above shall align vertically with the wall below.
Other conditions, such as offset walls, are not covered by this detail.
1g
Figures 3, 4 & 5a
Holes may be cut in web for
plumbing, wiring and duct work.
See Table 3 and Figure 6.
1e
Joist attachment per detail 1b
FILLER BLOCK REQUIREMENTS FOR
DOUBLE I-JOIST CONSTRUCTION
1p
Blocking required over all interior supports
under load-bearing walls or when floor joists
are not continuous over support
Flange
Width
NOTE: Never cut or notch flanges.
Glulam or Structural
Composite Lumber
(SCL) headers
Glulam or
SCL headers
Net
Depth
2-1/2"
2-1/2" nails at 6" o.c.
to top plate
PKI blocking panel per 1a
3-1/2"
1b
One of the benefits of using I-joists in residential floor construction is that holes may be cut in the joist webs to accommodate electrical wiring, plumbing lines
and other mechanical systems, therefore minimizing the depth of the floor system.
FIGURE 1
Filler
Block Size
9-1/2"
11-7/8"
14"
16"
2-1/8" x 6"
2-1/8" x 8"
2-1/8" x 10"
2-1/8" x 12"
9-1/2”
11-7/8"
14"
16"
3” x 6”
3" x 8"
3" x 10"
3" x 12"
Filler block
"
12
Offset nails from
opposite face by 6"
1/8" gap between top flange and filler block
Figures 3, 4 & 5a
1c
Use hangers recognized
in current CCMC reports
1j
1h
1p
1a
1n
1k 1m
1h
1f
Backer block (use if factored hanger load exceeds 360 lbs.)
Before installing a backer block to a double I-joist, drive 3
additional 3" nails through the webs and filler block where the
backer block will fit. Clinch. Install backer tight to top flange.
Use twelve 3" nails, clinched when possible. Maximum factored
resistance for hanger for this detail = 1620 lbs.
BLOCKING PANELS
PKI blocking
panel
1a
Blocking Panel or Rim Joist Maximum Factored Uniform Vertical Load* (plf)
PKI Joists
3300
*The uniform vertical load is limited to a joist depth of 16 inches or less and is
based on standard term load duration. It shall not be used in the design of a
bending member, such as joist, header, or rafter. For concentrated vertical load
transfer capacity, see 1d.
2-1/2" nails @ 6" o.c. to top plate (when used for lateral shear transfer, nail to
bearing plate with same nailing as required for decking)
Attach I-joist
to top plate
per 1b
APA
Rim Board
1b
Blocking Panel or Rim Joist
1-1/8" APA Rim Board Plus
1-1/8" APA Rim Board
1" APA Rim Board
Top- or
face-mounted
hanger
Double I-joist header
Note: Unless
hanger sides
laterally support
the top flange,
bearing stiffeners
shall be used.
BACKER BLOCKS (Blocks must be long enough to permit
required nailing without splitting)
Flange
Width
Material Thickness
Required*
Minimum
Depth**
2-1/2"
1"
5-1/2"
3-1/2"
1-1/2"
7-1/4"
Filler block
per Figure 1p
Backer block required
(both sides for face-mounted hangers)
For hanger capacity see hanger manufacturer’s
recommendations. Verify double I-joist capacity to
support concentrated loads.
* Minimum grade for backer block material shall be Utility grade SPF (south) or better for solid sawn lumber and Rated
Sheathing grade for wood structural panels.
** For face-mount hangers use net joist depth minus 3-1/4" for joists with 1-1/2" thick flanges. For 1-5/16" thick flanges use net
depth minus 2-7/8".
Maximum Factored Uniform Vertical Load* (plf)
8090
7340
5500
*The uniform vertical load capacity is limited to a rim board depth of 16 inches
or less and is based on standard term load duration. It shall not be used in the
design of a bending member, such as joist, header, or rafter. For concentrated
vertical load transfer capacity, see 1d.
Notes:
1. Support back of I-joist web during nailing to prevent damage to web/flange connection.
2. Leave a 1/8-inch gap between top of filler block and bottom of top I-joist flange.
3. Filler block is required between joists for full length of span.
4. Nail joists together with two rows of 3" nails at 12 inches o.c. (clinched when possible) on each side of the double I-joist. Total of 4 nails per
foot required. if nails can be clinched, only 2 nails per foot are required.
5. The maximum factored load that may be applied to one side of the double joist using this detail is 860 lbf/ft.
1j
Glulam or multiple structural composite lumber (SCL) beams
For nailing schedules for multiple SCL beams, see the manufacturer‘s recommendations
One 2-1/2" nail at top and bottom flange
I-JOIST WEB STIFFENERS
A web stiffener is a wood block that is used to reinforce the web of an I-joist at
locations where:
•The webs of the I-joist are in jeopardy of buckling out of plane. This usually occurs
in deeper I-joists.
•The webs of the I-joist are in jeopardy of “knifing” through the I-joist flanges. This
can occur at any I-joist depth when the design reaction loads exceed a specific level.
•The I-joist is supported in a hanger and the sides of the hanger do not extend up to
the top flange. With the top flange unsupported by the hanger sides, the joist may
deflect laterally, putting a twist in the flange of the joist. The web stiffener supports
the I-joist along a vertical axis as designed. (In this application, the web stiffener
acts very much like a backer block.)
There are two kinds of web stiffeners: bearing stiffeners and load stiffeners. They are
differentiated by the applied load and the location of the gap between the slightly
undersized stiffener and the top or bottom flange. (See Figure 2.)
Rules for cutting holes in PKI Joists
1. The distance between the inside edge of the support and the centerline of any hole shall be in compliance with the requirements of Table 5.
2. I-joist top and bottom flanges must NEVER be cut, notched or otherwise modified.
3. Whenever possible, field-cut holes should be centered on the middle of the web.
4. The maximum size hole that can be cut into an I-joist web shall equal the clear distance between the flanges of the I-joist minus 1/4 inch. A minimum of 1/8
inch should always be maintained between the top or bottom of the hole and the adjacent I-joist flange.
5. The sides of square holes or longest sides of rectangular holes should not exceed three-fourths of the diameter of the maximum round hole permitted at
that location.
6. Where more than one hole is necessary, the distance between adjacent hole edges shall exceed twice the diameter of the largest round hole or twice the
size of the largest square hole (or twice the length of the longest side of the l­ongest rectangular hole) and each hole must be sized and located in compliance
with the requirements of Table 5.
7. A knockout is not considered a hole, may be utilized anywhere it occurs and may be ignored for purposes of calculating minimum distances between holes.
8. Holes measuring 1-1/2 inches or smaller shall be permitted anywhere in a cantilevered section of a PKI Joist. Holes of greater size may be permitted subject
to verification.
9. A 1-1/2-inch hole or smaller can be placed anywhere in the web provided that it meets the requirements of rule number 6 above.
10. All holes shall be cut in a workman-like manner in accordance with the restrictions listed above and as illustrated in Figure 6.
11. Limit three maximum-size holes per span.
12. A group of round holes at approximately the same location shall be permitted if they meet the requirements for a single round hole circumscribed around them.
PKI JOIST TYPICAL HOLES -
•Holes in webs should be cut with a sharp saw.
3/4x
diameter
2x diameter
of larger hole
Top- or face-mounted hanger installed per manufacturer‘s recommendations
PKI rim joist per 1a
1c
Bearing stiffeners are located at the reactions, both interior and exterior, when
required.
Load stiffeners are located between supports where significant point loads are applied
to the top flange of an I-joist.
Attach rim joist to floor joist with one nail at top and bottom. Nail
must provide 1 inch minimum penetration into floor joist. For
2-1/2" and 3-1/2" flange widths, toe nails may be used.
Squash block
WEB STIFFENER INSTALLATION DETAILS
FIGURE 2
Attach rim joist to top plate per 1a
Minimum 1-3/4" bearing required
1d
Flange width
1-3/4"
or less
+ 1/16"
for squash
blocks
Pair of Squash Blocks
2x lumber
1-1/8" APA Rim Board,
Rim Board Plus, or
Rated Sturd-I-Floor 48 oc
1" APA Rim Board or
Rated Sturd-I-Floor 32 oc
Top-mounted hanger installed per manufacturer‘s recommendations
Maximum factored
vertical load per pair
of squash blocks (lb)
3-1/2" wide 5-1/2" wide
5800
9500
4500
5800
4000
5800
LOCATION OF CIRCULAR HOLES IN PKI JOIST WEBS - TABLE 5
2x plate flush with inside face of wall or beam
Note: Unless hanger sides laterally support the top flange, bearing stiffeners shall be used.
PKI or APA Rim Board
blocking panel per 1a
Flange width
greater than
1-3/4"
1/8"-1/4"
Gap
Approx.
2"
Clinch
Individual components not shown to scale for clarity.
Approx.
2"
OR
(4) 2-1/2"
nails clinched
1m
Provide lateral bracing per 1a, 1b, or 1c
Multiple I-joist header with full depth filler block shown. Glulam and multiple SCL
headers may also be used. Verify double I-joist capacity to support concentrated loads.
Approx.
2"
CONCENTRATED LOAD
(Load stiffener)
No Gap
Backer block attach per 1h. Nail with twelve 3" nails, clinch when possible.
Approx.
2"
SAF
PKI10-10
PKI20-10
END BEARING
(Bearing stiffener)
Tight Joint
No Gap
Gap
9 1/2”
1/8"-1/4"
Gap
See table above for web
stiffener size requirements
Maximum factored support = 1620 lbs.
Transfer load from above to bearing below. Install squash blocks per 1d.
Match bearing area of blocks below to post above.
1n
Do not bevel-cut joist beyond inside face of wall
Web stiffener blocks may be compromised of lumber, APA Rim Board or wood
structural panels. The wood structural panels should be Rated Sheathing or Single
Floor; minimum lumber grade is Utility grade SPF (south) or better.
Ideally, the depth of the web stiffener should equal the distance between
the flanges of the joist minus 1/8 inch to 1/4 inch. For bearing stiffeners,
this gap is placed bet ween the top of the s tif fener and the bot tom
of the top flange. For load stiffeners, the gap is located at the bottom of the stiffener.
Attach I-joist per 1b
Use single I-joist for factored loads up to 3300 plf, double I-joists for
loads up to 6600 plf (filler block not required). Attach I-joist to top plate
using 2-1/2" nails at 6" o.c.
Note: Blocking required at bearing for lateral support, not shown for clarity.
STIFFENER SIZE REQUIREMENTS
TABLE 3
PKI Flange Width
Provide backer for siding attachment unless nailable sheathing is used
Wall sheathing, as required
APA Rim Board may be used in lieu of I-joists. Backer is not required when
APA Rim Board is used.
All nails shown in the details above are assumed to be common nails unless otherwise noted. 10d box nails (0.128 x 3 in.) may be substituted for 8d common (0.131 x
2-1/2 in.) shown in details. Individual components not shown to scale for clarity.
Web Stiffener Size Each Side of Web
2-1/2"
1" x 2-5/16" minimum width
3-1/2"
1-1/2" x 2-5/16" minimum width
4
5
6
6 1/4
13.75
1'-1"
1'-2"
2'-2"
3'-6" 4'-11" 5'-4"
14.65
1'-1"
1'-2"
2'-2"
3'-8"
5'-3"
5'-8"
PKI35plus-10 15.84
1'-1"
1'-8"
3'-2" 4'-10" 6'-7"
7'-0"
7
8
8 5/8
9
10
10 3/4
2'-6"
4'-0"
5'-8"
7'-5" 7'-11"
PKI10-12
15.75
1'-1"
1'-2"
1'-2"
2'-3"
3'-5"
3'-9"
4'-9"
6'-2"
7'-4"
PKI20-12
17.33
1'-1"
1'-2"
1'-2"
2'-4"
3'-9"
4'-1"
5'-2"
6'-9"
8'-0"
11 7/8” PKI35plus-12 18.80
1'-1"
1'-2"
2'-1"
3'-7"
5'-1"
5'-6"
6'-9"
8'-6"
9'-8"
PKI40-12
20.09
1'-1"
1'-7"
3'-0"
4'-6"
6'-1"
6'-6"
7'-9"
9'-7" 10'-9"
PKI50-12
20.55
1'-1"
1'-2"
1'-2"
2'-2"
4'-0"
4'-6"
6'-0"
8'-1"
9'-6"
PKI10-14
17.25
1'-1"
1'-2"
1'-2"
1'-3"
2'-3"
2'-7"
3'-5"
4'-8"
5'-6"
6'-0"
7'-6"
9'-2"
PKI20-14
18.77
1'-1"
1'-2"
1'-2"
1'-3"
2'-3"
2'-7"
3'-6" 4'-11" 5'-9"
6'-4"
8'-0"
9'-9"
PKI35plus-14 21.29
1'-1"
1'-2"
1'-2"
2'-2"
3'-7"
4'-0"
5'-1"
6'-8"
7'-8"
8'-4" 10'-1" 11'-9"
14”
16”
11
12
12 3/4
Notes:
1'-1"
Tight Joint
No Gap
PHYSICAL DESCRIPTION:
3
16.93
1e
Filler block
per Figure 1p
Round Hole Diameter (in.)
2
PKI40-10
(4) 2-1/2" nails,
3" required for
I-joists with
3-1/2" flange
width (PRI-80s)
No Gap
Gap
Minimum Distance from Inside Face of Any Supports to Center of Hole (ft-in)
Joist
Series
Depth
Install hanger per manufacturer‘s recommendations
1f
•For rectangular holes, avoid
ove r- cu t t in g t h e c o r n e r s,
as this can cause unnecessar y stress concentrations.
Slightly rounding the corners
is recommended. Starting the
rectangular hole by drilling a
1-inch-diameter hole in each of
the four corners and then making the cuts between the holes
is another good method to minimize damage to the I-joist.
Simple or Multiple Span for Dead Loads up to 40 psf and Live Loads up to10 psf
1k
Attach I-joist per 1b
Knockouts are prescored holes often provided by I-joist manufacturers for the contractor’s convenience
to install electrical or small plumbing lines. They are typically 1-3/8 to 1-3/4 inches in diameter, and are
spaced 12 to 24 inches on center along the length of the I-joist. Where possible, it is preferable to use
knockouts instead of field-cutting holes.
To avoid splitting flange, start nails at least 1-1/2" from end of I-joist. Nails
may be driven at an angle to avoid splitting of bearing plate.
Note: Unless hanger sides laterally support the top flange, bearing stiffeners shall be used.
•Never drill, cut or notch the flange, or over-cut the web.
See rule 12
Minimum distance from face of support to the center of hole. See Table 3.
Attach APA Rim Board to top plate using 2-1/2" common or box toenails @ 6" o.c.
One 2-1/2" face nail
at each side at bearing
Cutting the Hole
FIGURE 6
(a)Tables may be used for I-joist spacing of
24 inches o.c. or less.
(b)Hole location distance is measured from
inside face of supports to center of hole.
(c)Distances in this chart are based on
uniformly loaded joists.
(d)Hole sizes and/or locations that fall
outside the scope of this table may be
acceptable based on analysis of actual
hole size, span, spacing and loading
conditions. The I-joist shear capacity at
the location of a circular web hole (Vrh) is
calculated using the following equation:
PKI40-14
22.76
1'-1"
1'-2"
2'-1"
3'-6"
5'-0"
5'-4"
6'-6"
8'-1"
9'-2" 9'-10" 11'-8" 13'-2"
PKI50-14
23.28
1'-1"
1'-2"
1'-2"
1'-3"
2'-8"
3'-1"
4'-5"
6'-3"
7'-6"
8'-3" 10'-5" 12'-1"
PKI20-16
20.12
1'-1"
1'-2"
1'-2"
1'-3"
1'-3"
1'-4"
2'-2"
3'-5"
4'-2"
4'-8"
6'-1"
7'-2"
7'-6"
PKI35plus-16 23.54
1'-1"
1'-2"
1'-2"
1'-3"
2'-1"
2'-5"
3'-6" 4'-11" 5'-10" 6'-5"
8'-0"
9'-3"
9'-9" 11'-11" 13'-8"
PKI40-16
25.15
1'-1"
1'-2"
1'-2"
1'-3"
2'-7" 2'-11" 4'-0"
PKI50-16
25.73
1'-1"
1'-2"
1'-2"
1'-3"
1'-3"
9'-5" 11'-6"
5'-6"
6'-8"
7'-4"
9'-4" 10'-10" 11'-4" 13'-7" 15'-5"
1'-7" 2'-10" 4'-6"
5'-8"
6'-4"
8'-3"
9'-8" 10'-3" 12'-4" 14'-3"
Vrh = Published Shear Value x [(Joist Depth –
Hole Diameter) / Joist Depth]
(e)SAF = Span Adjustment Factor, used as defined below:
OPTIONAL:
Table 5 is based on the I-joists used at their maximum span. If the I-joists are placed at less than their full allowable span, the maximum distance from the centerline of the hole to
the face of any support (D) as given above may be reduced as follows:
Lactual
xD
Dreduced =
SAF
Where: Dreduced=Distance from the inside face of any support to center of hole, reduced for less-than-maximum span applications (ft). The reduced distance
shall not be less than 6 inches from the face of the support to edge of the hole.
Lactual =The actual measured span distance between the inside faces of supports (ft).
SAF =S pan Adjustment Factor given in this table.
D
=The minimum distance from the inside face of any support to center of hole from this table.
Lactual
Lactual
If
is greater than 1, use 1 in the above calculation for
SAF
SAF
JAN 2015-FID-SS-CA
Complete Specifier Guide available at
www.PinkWood.ca