- High-Density Polypropylene Construction: Molded from durable, impact-resistant black polypropylene engineered to withstand harsh weathering, UV exposure, and heavy jobsite debris without cracking or warping.
- Optimized Large Sump Flow Profile: Features an open-slot dome design with a 13-inch outside diameter and 4½-inch height, maximizing water intake capacity while screening out damaging rooftop debris.
- Exact Josam 21500-Series Fitment: Engineered precisely as a direct-fit replacement component for Josam 21500-series large sump commercial roof drains, ensuring a flush and seamless match.
- Fast Snap-In Maintenance Setup: Designed for straightforward, hardware-free alignment and seating over the drain opening, allowing roofing contractors to complete replacements and clear blockages quickly.
Price: $79.55
Item #316-029273
Write a review!
Description
The Josam 21504 Poly Dome is manufactured from durable black polypropylene and fits the Josam 21500-series roof drains. It features a 13-inch outside diameter and a height of 4½ inches. This component helps prevent debris entry while maintaining full drainage capacity.
Key Features
-
Material: polypropylene
-
Outside diameter: 13 inches
-
Height: 4½ inches
-
Color: black
-
Designed to fit Josam 21500-series large sump roof drains
Specifications
Manufacturer: Josam Company
Model/SKU: 21504
Material: Polypropylene
Outside diameter: 13 inches
Height: 4½ inches
Color: Black
Quantity: Kits sold individually
Gate: Not included (sold separately)
How To
- Remove any existing dome or grate from the Josam 21500-series roof drain body.
-
Align the new 21504 Poly Dome over the drain opening so it sits flush and centered on the drain lip.
-
Secure the dome per manufacturer instructions (typically locks or snaps into place).
-
Check for a proper fit and ensure no gaps exist for debris to bypass.
-
Run a flush test to confirm free area and drainage efficiency.
FAQs
Q: Can the 21504 Poly Dome be used on any Josam roof drain model?
A: The 21504 is designed specifically for the Josam 21500-series large sump roof drains; compatibility with other series should be verified.
Q: What is the purpose of the dome’s large free area design?
A: It maximizes drainage capacity and prevents debris from entering the drain sump or piping system.
Q: How often should the dome be inspected or replaced?
A: Inspect the dome during routine roof maintenance or after heavy storms; replace if any cracks or warping appear.
Q: Does the dome include mounting hardware or clamps?
A: The 21504 Poly Dome is sold as a stand-alone component without hardware or clamp rings.
Reviews (0) • Write a review!
This product has no reviews yet. Write a review!
Josam 415 - Cast Iron Drain Ring
Outside diameter 15-1/4"
Price: $439.95
Availability: In Stock
Usually ships within 1-2 Business Days
The Josam 415 Cast Iron Clamp Ring is constructed from coated cast iron in a green finish and is designed for use with select Josam roof drain bodies. It features an outside diameter of 14-3/4 inches, a 180° bolt-to-bolt diameter of 11-1/2 inches, and a bolt-to-bolt spacing of 8 inches. The ring securely clamps the roofing membrane or flashing to the drain body, creating a watertight seal. Key Features Material: cast iron Color: green Outside diameter: 14-3/4 inches 180° bolt-to-bolt diameter:...
Josam 22010 - Cast Iron Drain Ring
Outside diameter 10-15/16"
Price: $164.40
Availability: In Stock
Usually ships within 1-2 Business Days
The Josam 22010 Cast Iron Clamp Ring is made of coated cast iron with a green finish and is designed for use with medium sump roof drains in the Josam 22010 series. It features an approximate outside diameter of 11 inches, a 9-inch 180° bolt-to-bolt diameter and 6½-inch bolt-to-bolt spacing. The ring secures the roofing membrane or flashing to the drain body to provide a watertight seal. Key Features Material: cast iron Color: green Outside diameter: approximately 11 inches 180° bolt-to-bolt...
Josam 21504-22 - Cast Iron Dome
Outside diameter 13"
Price: $159.95
Availability: In Stock
Usually ships within 1-2 Business Days
The Josam 21504-22 Cast Iron Dome is constructed from cast iron in a green finish and is designed for use with the Josam 21500-series large sump roof drains. It has an outside diameter of 13 inches and a height of 4½ inches. The design covers the drain opening and allows water to flow while helping to prevent large debris from entering. Key Features Material: cast iron Outside diameter: 13 inches Height: 4½ inches Color: green Designed to fit Josam 21500-series large sump roof drains ...
Josam 22080 - Cast Iron Dome
designed for smaller roofs, gutters, or valleys
Price: $95.95
Availability: In Stock
Usually ships within 1-2 Business Days
The Josam 22080 Cast Iron Dome is made from coated cast iron in a beehive shape and pairs with the Josam 22080 series small-sump roof drains. It features an approximate outside diameter of 9 ¼ inches and a height of 5 ½ inches. The dome offers a free drainage area of about 37.6 square inches and is designed to intercept debris while maintaining effective water flow. Key Features Material: cast iron Outside diameter: approx. 9 ¼ inches Height: approx. 5 ½ inches Free drainage area: approx. 37.6...