Roof curb installation instructions for trapezoidal standing seam roof.

1. R O O F C U R B I N S TA L L AT I O N I N S T R U C T I O N S :
T R A P E ZO I D A L S TA N D I N G S E A M PA N E L
p: (800) 284-1412 f: (903) 759-3598 www.lmcurbs.com 827 fisher rd longview, tx 75604

2. ROOF CURB
INSTALLATION INSTRUCTIONS
TRAPEZOIDAL STANDING SEAM PANEL
Installation Check List:
_____Attach Sub-Frames Step 1
_____Layout Curb on Roof Panel Step 2
_____Back-up Channels Step 3
_____Apply Sealants & Set Curb in Place Step 4
_____Fasten Curb to Roof Panel Step 5
_____Attach Cap Strips Step 6
PARTS LIST
Flat Washer Polyurethane Sealant Caulk
Triple Bead Sealant Tape
Nut
14 Gauge Galvanized Steel Subframe
Bolt 5-1/2” tall
Length is equal to the purlin spacing minus
1-3/8”
Mounting Clip
Cap Strip
#14 - 1 1/8” Neoprene
Self-Tap Screw
Back-up Channels( eld notch)
BEGIN INSTALLATION
1 ATTACH SUB-FRAMES (framed opening is already installed)
Attach mounting clips to sub-frame and align the top of the sub-frame under Roof Purlin
Sub-frame
vertical box of roof curb and ush to the bottom side of roof sheets. Use the
mounting clip as a template, mark on purlin where 7/16” holes are to be drilled.
Once holes are drilled, attach mounting clips to purlins using at washers, nuts,
and bolts (see drawing 1.1). Finger tighten all hardware, then upset threads to
secure nuts. Attach sub-frames to mounting clips using at washers, nuts, and Drawing 1.2
bolts (see drawing 1.2). Flat washer
Nut
3/8” x 1” Bolts
Mounting clip
Drawing 1.1
Roof Purlin
*NOTICE* Sub-frame max. loading 500 lbs.
WARNING! Page 1
ALWAYS USE FALL PROTECTION WHILE
WORKING AROUND ROOF OPENINGS.

3. ROOF CURB
INSTALLATION INSTRUCTIONS
TRAPEZOIDAL STANDING SEAM PANEL
2 LAYOUT CURB ON ROOF PANEL
Mark cut lines by setting roof curb(s) in place on roof panel (see
Cut Line
drawing 2.1) (DO NOT USE LEAD PENCIL). Upslope cut line will be s 7”
inu
r bm
3” less than outer edge of curb base ange (see drawing 2.2). o f cu
gth
Downslope cut line will be 4” less than outer edge of base ange Len
(see drawing 2.2). Remove exterior panel leaving the insulation
face showing (see drawing 2.3) and cleanup all metal shavings and
debris.
Drawing 2.1
Top View Roof Panel
Layout throat opening on the insulation Throat Opening
Roof Opening
and cut opening (see drawing 2.2).
Insulation
Cu
rb
Ba ge
se n
Fla
ng Fla
e B ase
Drawing 2.3 rb
Cu
Drawing 2.2
*Notice* Sub-frames and purlins not shown in the above picture.
3 BACK-UP CHANNELS
Notch back-up channels (see drawing). Slide back-up channels
under roof panel on top of sub-frames. Do not screw back-up Edge of roof opening
channels to subframes. They will be secured when curb is
fastened down.
Cut leg of channel and fold under to form
notch for sub-frame (typically 4 places).
Back-up Channel
Ce
nte
Ou r Lin Back-up channels in place
tsid eo
eD fS
im ub Drawing 3.1
en -Fr
sio am
no e
fB
ac k
-up
Ch
a nn
el
WARNING! Page 2
ALWAYS USE FALL PROTECTION WHILE
WORKING AROUND ROOF OPENINGS.

4. ROOF CURB
INSTALLATION INSTRUCTIONS
TRAPEZOIDAL STANDING SEAM PANEL
4 APPLY SEALANTS & SET CURB IN PLACE The upslope highs are to be
Apply a strip of sealant tape and generous bead of caulk on the installed UNDER the roof panel.
upslope side of the roof curb and on downslope side of the roof
panel before setting roof curb in place (see drawing 4.1). Position
roof curb over roof opening and lower into place, shift curb to Roof Curb
align with sub-frames and roof panel.
Roof Panel
The downslope highs are to be
installed OVER the roof panel.
Caulk
(apply as shown)
Caulk Sealant Tape
(apply as shown)
Drawing 4.1
*Notice* Sub-frames and purlins not shown in the above picture.
Must ll end of standing
5 FASTEN CURB TO ROOF PANEL seam with caulk.
Fasten curb to roof panel using #14 - 1 1/8” neoprene self-tap screw Roof Panel
on 4” centers (see drawing 5.1). DO NOT FASTEN CURB OR ROOF
PANEL TO SUB-FRAMES. Please ensure all self-tap screws are
properly tightened before moving to the next step.
Self-Tap Screws
Drawing 5.1
*Notice* Sub-frames and purlins not shown in the above picture.
WARNING! Page 3
ALWAYS USE FALL PROTECTION WHILE
WORKING AROUND ROOF OPENINGS.

5. ROOF CURB
INSTALLATION INSTRUCTIONS
TRAPEZOIDAL STANDING SEAM PANEL
6 ATTACH CAP STRIPS
Turn the cap strips upside down and apply sealant tape to the entrie length of both
inside legs. Then run a bead of caulk down the middle of the cap strips and Roof Panel
at each end of cap strip (see drawing 6.1). Install cap strips over the
curb/roof panel sidelap, fasten with screws alternating on 6”
centers (staggered on both sides). The capstrip should
extend approximately 6” past both upslope and
downslope base of roof curb.
Cap strips furnished with curb
Sealant tape Caulk Cap Strips
Screws staggered 6” on center (length varies)
(both sides)
Curb base Roof Panel Sealant tape
(both sides)
Caulk
Drawing 6.1 1” between each bead
of caulk at each end
*Notice* Sub-frames and purlins not shown in the above picture.
COMPLETED INSTALLATION
**Clean up installation debris before leaving area.
WARNING! Page 4
ALWAYS USE FALL PROTECTION WHILE
WORKING AROUND ROOF OPENINGS.