---
title: Watts RD-100-85 IRMA Roof Drain Specs
description: Find Watts RD-100-85 IRMA roof drain specifications, outlets, dome types and accessories.
---

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# Watts RD-100-85 IRMA Roof Drain Specs

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

 

### ![watts-rd-100-85.png](https://cdn11.bigcommerce.com/s-7wb5vs0sib/product_images/uploaded_images/watts-rd-100-85.png "watts-rd-100-85.png")

**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.

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

 

### 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)

### Accessories

- 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)

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