Technical Specifications

P. 1 7
Typical Floor Framing Installation Notes
Web Hole Rules and Specifications
1� Installation of P3 Joist shall be in accordance with Figure 1�
2� Except for cutting joist to length, P3 Joist flanges should NEVER be
cut, drilled, or notched�
3� Concentrated loads should be applied only to the top surface of
the top flange� At no time should concentrated loads be suspended
from the bottom flange with the exception of light loads such as
ceiling fans, light fixtures, etc�
4� P3 Joist must be protected from the weather prior to installation�
5� P3 Joist must not be used in applications where they will be per-
manently exposed to weather or will reach a moisture content
greater than 16% such as in swimming pool or hot tub areas� They
must not be installed where they will remain in direct contact with
concrete or masonry�
6� End-bearing length must be at least 1-3/4”� For multiple span
joists, intermediate bearing length must be at least 3-1/2”�
7� Ends of floor joists shall be restrained to prevent rollover� Use
Certified Rim Board or P3 Joist blocking panels�
8� P3 Joist installed beneath bearing walls perpendicular to the
joists require full depth blocking panels, Certified Rim Board, or
squash blocks (cripple blocks) in order to transfer gravity loads
from above the floor system to the wall or foundation below� See
note 2g page 11�
9� For P3 Joist up to 18” deep installed as rim board directly
beneath bearing walls parallel to the joists, the maximum verti-
cal load using a single P3 Joist is 2000plf and using double P3
Joist is 4000plf� Full bearing is required under P3 Joist used as
rimboard�
10� Continuous lateral support of the P3 Joist’s compression flange
is required to prevent rotation and buckling� In simple span uses,
lateral support of the top flange is normally supplied by the floor
sheathing� In multiple span or cantilever applications, bracing of
the P3 Joist’s bottom flange is also required at interior supports
of multiple-span joists and at the end support next to the can-
tilever extension� The ends of all cantilever extensions must be
laterally braced as shown in Figure 3 or 4�
11� Nails installed perpendicular to the wide face of the flange shall be
spaced in accordance with the applicable building code require-
ments or approved building plans but should not be closer than
2”o�c� per row�
12� Figure 1 details show only P3 Joist-specific fastener require-
ments� For other fastener requirements, see the applicable
building code�
13� For Fire-Resistance ratings, typical Sound Transmission Class
(STC), and typical Impact Insulation Class (IIC) refer to ICC ESR
1405 Section 4�2�2 or DCA 3 – Fire Rated Wood Floor and Wall
Assemblies at www.awc.org�
One of the benefits of using P3 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, thereby mini-
mizing the depth of the floorsystem�
Rules for Cutting Holes in P3 Joists
1� The distance between the inside edge of the support and the
center line of any hole shall be in compliance with the require-
ments of Table 9�
2� P3 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 a P3 Joist web shall equal
the clear distance between the flanges of the P3 Joist minus1/4”�
A minimum of 1/8” should always be maintained between the top
or bottom ofthe hole and the adjacent P3 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 9�
7� Holes measuring 1-1/2” shall be permitted anywhere in a can-
tilevered section of a P3 Joist� Holes of greater size may be
permitted subject to verification�
8� A 1-1/2” hole can be placed anywhere in the web provided that it
meets the requirements of rule 6 above�
9� All holes shall be cut in a workman-like manner in accordance
with the restrictions listed above and as illustrated in Figure 6�
10� Limit of 3 maximum size holes per span�
11� 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�