Rim Board (RB)

A structural-rated 1-1/8” or 1-1/4" thick Engineered Wood Rim Board Plus with pre-machined modular receptacles spaced at 16”, 19.2” or 24” OC.  Receptacles are shaped to receive and conform to the end cross-section of a specific wood I-joist to save installation time and assure accurate vertical alignment and positioning.





  • Modular Receptacles provide precise spacing and vertical alignment without individual measuring.  
  • Receptacles improve resistance to I-joist rollover during and after construction.
  • Web slots help restrain I-joist web from buckling under vertical load.
  • Potentially increases lateral shear capabilities for floor structures.
  • Receptacles “lock-in” the ends of I-joists in cantilevered floor and roof rafter-tail assemblies to resist I-joist twisting under load.
  • Reduces installation time and labor costs.  (RB is not orientation specific... it can be reversed, mirrored or flipped as necessary.)
  • And much more… (see Product Bulletin under LITERATURE section for installation details)



It's easy laying out a floor with I CHOICE Rim Board (RB).  Each RB has one "full-end" and one "half-end".  The full-end has the full on-center spacing from the end of the RB to the next adjacent I-joist receptacle.  The half-end has half the on-center spacing from the end of the RB to the next adjacent receptacle.   To start a layout, simply align the "full-end" of a RB to a "reference corner" and toe-nail in place.



Stabilize the "reference corner" by installing a perpendicular RB with its "full-end" also at the corner.  If you wish to maintain precise modular spacing on the perpendicular RB, first cut off a portion of the "full-end" equal to the thickness of the RB itself... either 1-1/8" or 1-1/4".

Additional lengths of RB are easy to add... just match additional RB pieces "half-end" to "half-end".  RB can be cut to length as needed to finish a run... or to create a "half-end" for extending an existing run.  To create a half-end, simply cut off a section of the full-end equal to half the on-center spacing... or cut exactly between two existing modular receptacles.


Installation TIPS:


#1 -- Floor perimeter off-sets are no problem.  To maintain modular spacing at the offset, use the remaining portion of the RB used to complete the original run... and install it as the first RB of the offset portion.  Then continue the off-set run by matching RB pieces half-end to half-end.


#2 -- Adding additional I-joists or structural beams to a modular floor lay-out is no problem.  The modular spacing can always be "over-riden".  Additional structural members can be added anywhere to the modular layout just like with conventional Rim Board... at the specified measured locations on the plan.  Not all structural members are required to have their own specific receptacle.  Additional I-joists or beams may be abutted to the inside of the RB, or may be cut through so as to penetrate the RB... and be flush with the outer edge of the floor.