Technical Specifications

21
WINDOW/DOOR JAMBS
A minimum gap of 1/4” is required when
butting panels into windows, doors, and
trim boards.
SINGLE FLANGE SEALANT BACKER:
Install the Single Flange Sealant Backer first,
butting to the door/window jamb or trim
pieces prior to installing the panels.
The Single Flange Sealant Backer must be
fastened a minimum of 12” to 14” o.c. to
studs, blocking, or structural sheathing.
Cut panel to appropriate width, at least
removing ship-lapped edge. Remember to
clean freshly cut panels with a soft, dry cloth.
Install panels and fill gap with ASTM C-920
compliant sealant. (Figure 43)
J-MOLD: Pre-install J-Mold trim with a ¼”
gap between it and the window/door jamb.
Panels must fit completely within trim, with
no exposed panel edges, but leaving a 1/8”
space between panel edge and J-Mold. Place
foam backer rod inside the channel to help
create this gap.
Lastly, add closed-cell foam backer rod and
sealant to the ¼” gap between the J-mold
and jamb.
NICHIHA CORNERS AT RECESSED JAMBS:
Nichiha Corners can be used to wrap recessed
window jambs. Corners have returns of 3-1/2”
(face dimension). Cut piece as needed for
shallower returns.
Wrap base of jamb with cut pieces of Starter
Track (or FS1010 Spacer if face fastening)
Install Corner pieces at jamb prior to main
panels using cut Panel Clips (refer to Cutting
Panel Clips section). Cut clips must retain
at least one downward panel engagement
flange.
Install Single Flange Sealant Backer with
the sealant bump against the Corner piece,
fastening at 12” - 14” o.c. along the fastening
flange. (Figure 44)
Where Corner piece meets termination point
at window, leave minimum ¼” gap and add
½” closed-cell backer rod and sealant.
Refer also to Outside Corners section for
alternative approach.
Fig. 43
Single Flange Sealant Backer
NICHIHA FACTORY
CORNER OVER
CUT PANEL CLIPS
SINGLE FLANGE
SEALANT BACKER
3-1/2"
Fig. 44