R-Guard Installation Detail

Arched Window Rough Opening

CMU/cast-in-place concrete wall construction

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Arched wood framing and plywood sheathing is installed and detailed at inside 90 degree and corner splices with FastFlash or Joint & Seam Filler in preparation to receive FastFlash liquid-applied flashing membrane.


FastFlash covers the entire wood surface, terminating at the edge of the wood-to-CMU interface.


Radius windows are installed and placed into the opening, allowing the shims to be recessed to allow a backer rod and bead of AirDam to be continuously tooled around the inside perimeter of the window.


Fin/flange windows can be set in a bed of wet FastFlash at jamb/head/jamb locations, leaving the sill open. Shims beneath the flange should be set at quarter points of the window to allow for appropriate drainage. An exterior weather bead of sealant can be installed, allowing for weep/drainage points to take place at the sill location(s).

Ted Barnekoff - Air & Water Barriers, PROSOCO

Ted Barnekoff
Product Support - Air & Water Barriers


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