2 EACH
CUT 1/4" PLYWOOD AND
PANEL INSIDE OF I-JOISTS
2 EACH
29 3/4"
58 3/4"
JOIST
JOIST
I-Joist
Hanger
Optional Framing Technique #2
FOR I-JOISTS ON 16” CENTERS:
(This technique requires that you have additional I-Joist
of the same size as that used in your ceiling. If you do not
have additional I-Joist, see the technique on page 10.)
I-Joists differ from solid lumber in that the “I” shape beam
is too narrow for “end nailing” when attaching one I-Joist
perpendicular to the face of another. Furthermore, the
face of an I-Joist is inset, making it less than an ideal
surface to join something to. One way to address both
problems is to install blocking on the ends of I-Joist
sections and headers. For details about using blocking,
see Figs. 14 & 17 on pages 9 & 10.
OPTIONS FOR FRAMING THE OPENING
Because I-Joists are typically 2.5” wide (solid wood joists
are 1.5”), cutting one I-Joist only creates a rough opening
of 29.5” when 31” is required (see Fig. 9). To resolve this
problem, you must either set one joist off-center by 1.5”
(see Fig. 10) -OR- you will need to cut two joists and
install a stringer in order to get the required opening
width of 31” (see Fig. 11). Note the rough opening must
be 31” x 59” (½”oversize) so that it can be paneled with
1/4” plywood (see Fig. 12). After paneling the finished
opening will be 58.5” x 30.5” with smooth sidewalls.
Note: I-Joist hangers can be used instead of blocking.
Finish opening with 1/4” paneling to cover hangers
and create a smooth-sided opening (Fig. 12), then
install 2 x 2” flashing in every corner (Fig. 2b, pg. 5).
Fig. 12
Fig. 11
Fig. 9
Fig. 10
INSTALL 2 x 2”
FLASHING INSIDE
FINISHED OPENING
8
Versa Lift
Installation -
Framing Techniques
Optional
14.5"
O.C.
16"
O.C.
16"
O.C.
O.C.
16"
O.C.
17.5"
MUST BE
31" WIDE!
59"
29.5"
THESE JOISTS MAY
NEED TO BE DOUBLED
FOR ADDED STRENGTH
30.5"
58.5"
OPTION #2:
TWO I-JOISTS ARE
CUT AND AN
I-JOIST STRINGER
IS INSTALLED
INSTALL
STRINGER
31"
59"
59"
OPTION #1:
ONE JOIST IS
SHIFTED 1.5"
(MORE OR LESS)
OFF-CENTER
31"
FINISHED
OPENING
58.5 x 30.5"
WARNING!
CUTTING ONE I-JOIST
ON 16" CENTERS
WILL NOT PROVIDE A
31" WIDE OPENING!
Depending on location
and code requirements,
web stiffeners may be
required for I-Joist when
using hanger brackets.
Web Stiffener
