Installation Guide

Floor Construction
ENGINEERED WOOD CONSTRUCTION GUIDE
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FORM NO. E30V
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© 2011 APA – THE ENGINEERED WOOD ASSOCIATION
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WWW.APAWOOD.ORG
35
APA Performance Rated Rim Board
®
A Rim Board is the wood component that fills the space between the sill plate and bottom plate
of a wall or, in second floor construction, between the top plate and bottom plate of two wall sec-
tions. The Rim Board must match the depth of the framing members between floors or between the
floor and foundation to function properly. In addition to supporting the wall loads, the Rim Board
ties the floor joists together. It is an integral component in an engineered wood system because it
transfers both vertical bearing and lateral forces.
While lumber has been the traditional product used for Rim Boards, it is generally not compatible with the depth of the new
generation of wood I-joists used in floor construction. With the increasing use of wood I-joists, a demand for compatible
engineered wood Rim Boards has resulted.
APA Performance Rated Rim Boards can be manufactured using plywood, oriented strand board (OSB), glulam, or
structural composite lumber (SCL). These engineered wood Rim Boards have less shrinkage than lumber and match
the depth of wood I-joists and other engineered wood framing products. They are available in lengths up to 24 feet,
depending on the product used.
APA Performance Rated Rim Boards are manufactured in accordance with Voluntary Product Standards PS 1 or PS 2, or
ANSI/AITC A190.1 and meet the requirements of ANSI/APA PRR 410 Standard for Performance-Rated Engineered Wood Rim
Boards or APA PRR-401 Performance Standard for APA EWS Rim Boards. ANSI/APA PRR 410 and APA PRR-401 meet or exceed
the requirements given in the ICC ES Acceptance Criteria for Wood-Based Rim Board Products, AC124.
As glued engineered wood products, APA Rim Boards have greater dimensional stability, higher strength, increased
structural reliability, more consistent quality and a lower tendency to check or split than sawn lumber.
The APA Glued Floor System
The APA Glued Floor System
is based on thoroughly tested
gluing techniques and field-
applied construction adhesives
that firmly and permanently
secure a layer of wood struc-
tural panels to wood joists.
Stagger end joints
APA RATED STURD-I-FLOOR
or APA RATED SHEATHING
2x rim joist
or APA Rim
Board
1/8" spacing is
recommended at all edge
and end joints unless
otherwise indicated by
panel manufacturer
2x joists,
I-joists or floor
trusses – 16", 19.2",
24", or 32" o.c.
(4x supports for
48" o.c. spacing)
FIGURE 4
APA GLUED FLOOR SYSTEM
Strength axis
Site-applied glue,
both joints and
tongue-and-
groove joints (or
between panels
and edge
blocking)
Tongue-and-groove
edges (or 2" lumber
blocking between
supports)
Notes:
1. Provide
adequate moisture
control and use
ground cover vapor
retarder in crawl
space. Panels must be
dry before applying finish
floor.
2. For buildings with wood or steel
framed walls, provide 3/4" temporary
expansion joints with separate floor framing
members and discontinuous wall plates over the
joints, at intervals that limit continuous floor areas to 80
feet maximum in length or width, to allow for accumulated
expansion during construction in wet weather conditions.
Refer to APA Technical Note: Temporary Expansion Joints for
Large Buildings, Form U425, for detailed information.
2x treated
sill
Rim Board
®
is a registered trademark of APA – The Engineered Wood Association.