Watts RD-100-85 IRMA Roof Drain Specs

Dimensional data is subject to manufacturing tolerances and change without notice. 


Pipe Size (in.)
2" (-2)
3" (-3)
4" (-4)
5" (-5)
6" (-6)

Specifications: The Watts Drainage RD-100-85 is an epoxy-coated, cast-iron IRMA roof drain with flashing clamp. It includes a 4-in. high stainless steel perforated extension; self-locking polyethylene dome; and no hub (standard) outlet. 137 sq. in. free area. 



Outlet Types

No-Hub Outlet (-NH)
Push On (-P)
Threaded Outlet (-T)
Inside Caulk (-X)



Optional Body Material

PVC Body w/ Socket Outlet (-60)
ABS Body w/ Socket Outlet (-61)







Galvanized Body and Flashing Clamp (-13) Rough Bronze Dome (-K81)
Accutrol Flow Restrictor (-A) Aluminum Dome (-K80)
Sump Receiver (-B) Stainless Steel Mesh Covered Dome (-K83)
Underdeck Clamp (-D) Vandal Proof Dome (-L)
Adjustable Extension Flange (-F) 2-in. External Water Dam (-R)
Stainless Steel Ballast Guard (-GSS) Side Outlet (2, 3, 4 in. only) (-SO)
Ductile Iron Dome (-K) Fixed Extension (1-1/2., 2, 3, 4 in.) (-V)
Galvanized Dome (-K13) Buy American Compliant (-US)
Ductile Iron Low Dome (4-in. high) (-K40) 4-in. Internal Water Dam (-W)