Instructions / Assembly
STEP 1 Rough opening should be plumb and level. Install 12” waterproofing membrane as a drainage skirt, 6” above 
bottom plate and fold it over the bottom plate. Apply 5 beads of Henkel/OSI TeQ Sealant 3/8” diameter, two on the each 
edge of the bottom plate, one on exterior sheeting ¼” below bottom plate and one in each inside corner. 
STEP 2 Cut Channel Plate™ ¼” less than the rough opening and place it on the bottom plate. First Drain Channel should 
be minimum 2” away from the edge. Fasten Channel Plate™ with fasteners to the bottom plate 1” from each edge.  
STEP 3  
A. Remove first piece of release paper from SureSill™ FlexCap™. Adhere SureSill™ FlexCap™ to first Drain Channel and 
Front Lip. If needed, stretch FlexCap™ over the slope and back lip. Do not stretch FlexCap™ over the Front Lip. Continue 
to adhere towards the rough opening (RO).  Adhere FlexCap™ over mechanical fastener and the closest Drain Channel 
after mechanical fastener (First Drain Channel).  
B. Remove second piece of release paper and adhere FlexCap™ up the rough opening a minimum 2”. 
C. Fan out SureSill™ FlexCap™ at bottom corners onto 
face of wall. Coverage of SureSill™ FlexCap™ should be  
2” to 3” onto the face of the wall and over Front Lip.  
Front View 
Back View 
Fastener Detail 
Drain Channel 
First Drain 
Channel 
SURESILL™ FLEXCAP™
INSTALLATION GUIDELINES FOR 11X™ AND FOR  
FIXED SIZE SLOPED SILL PAN™  
First Drain 
Channel 
Front Lip 
Fastener Detail 
SureSill 11X Sloped Sill Pan and FlexCap is a Patent Pending Technology made only by Suresill, Ltd. SureSill
TM
, Sloped Sill Pan™, 11X™, and 
FlexCap™ are the exclusive trademarks of SureSill, Ltd. © Copyright SureSill, Ltd. 2008 - 2011. All rights reserved.  20101002 
3 
NOTE: Proceed with Steps 3 – 5 of the SureSill Water 
Management Guide posted at www.suresill.com for 
installation of the complete SureSill system. FlexCaps™ can 
be exposed to UV 120 days before they need to be covered. 
Sealant Detail 
SureSill™ 
FlexCap™ Detail 
Drainage Skirt over 
exterior sheeting 
E. Fold SureSill™ FlexCap™ on back side to complete end dam. Repeat the same for other side. 
D. Apply 3/8” thick bead of Sealant at the edge of FlexCap™ and 
11X Pan and tool it flat. Sealant should not obstruct the drainage. 
FlexCap™ Detail 
Sealant Detail 
SureSill™ 
FlexCap™ 
Detail - Back 





