Description
12″ Heavy Duty Cast Iron Catch Basin Frame and Grate
Amercast’s 12″ Heavy Duty Cast Iron Catch Basin Frame and Grate is engineered for the demands of municipal roadway drainage — heavy vehicle loads, constant water flow, and the unforgiving standards of public works specifications. Cast from grey iron conforming to ASTM A48 Class 30B, this 12×12 square unit delivers the compressive strength, corrosion resistance, and dimensional consistency that civil engineers and contractors rely on for long-service stormwater infrastructure. Class 35B also available upon fabrication re
Rated AASHTO H-20 / AASHTO M-306 Class C (Heavy Duty), this catch basin frame and grate is suited for roadways, parking lots, driveways, and municipal drainage systems where standard vehicular traffic loading applies. Amercast has supplied drainage castings for major projects across the New York City infrastructure network — including work for the various Municipal Department of Transportations, MTA, JFK Airport, and LaGuardia Airport — backed by over 35 years serving the sewer, waterworks, and construction industries.
In stock. Ready to ship.
Why This Catch Basin Grate
Catch basins are the first line of defense in stormwater management. A frame that rocks, rattles, or fails under load creates a road hazard, accelerates pavement damage, and triggers costly emergency replacements. Amercast’s 12″ unit is manufactured to prevent all three failure modes.
ASTM A48 Class 30B grey iron — the proven standard for load-bearing street hardware. Grey cast iron has been the material of choice for municipal castings for over a century. Its graphite microstructure provides natural vibration damping, excellent compressive strength, and inherent corrosion resistance that does not depend on a surface coating. ASTM A48 Class 30B delivers a minimum 30,000 psi tensile strength — the standard for heavy-duty construction castings in road and drainage applications.
Engineering and Material Standards full material and load class detail, visit our Engineering and Material Standards page.
AASHTO M-306 compliance means it has been proof-load tested. Per AASHTO M-306, H-20 heavy-duty castings must sustain a 40,000-pound proof load applied on a 9×9-inch contact area for a minimum of one minute without cracking or permanent deformation — a 2.5x safety factor over the standard H-20 wheel load of 16,000 lbs. Every Amercast heavy-duty casting is held to this benchmark.
12×12 square format means broad compatibility. The compact 12-inch square footprint pairs with the most common small-to-mid precast concrete catch basin structures used throughout the Northeast and Mid-Atlantic. It is the entry-level heavy-duty size in the Amercast catch basin lineup and the most widely stocked for fast-turnaround municipal replacement work.
Technical Specifications
Product Type — Frame and Grate, sold as a matched set Nominal Size — 12″ x 12″ (square) Frame Height / Depth — 3 inches Material — Grey Cast Iron Material Standard — ASTM A48, Class 30B Load Rating — AASHTO H-20 / AASHTO M-306 Load Class — Class C (Heavy Duty) Proof Load — 40,000 lbs (per AASHTO M-306) Finish — Black asphaltic coating (standard)
Key Features
- ASTM A48 Class 30B grey cast iron — 30,000 psi minimum tensile strength; the proven standard for load-bearing municipal street castings
- AASHTO M-306 / H-20 rated — proof-load tested to 40,000 lbs; meets or exceeds NYC DOT, state DOT, and municipal public works specifications
- Class C Heavy Duty designation — rated for standard vehicular traffic including roads, intersections, commercial driveways, and parking facilities
- 3″ frame depth — proper seating depth for integration into standard precast concrete catch basin structures
- 12×12 square geometry — compatible with the most widely used small precast basin configurations across New York, New Jersey, Connecticut, and surrounding states
- Black asphaltic finish — standard corrosion-resistant coating consistent with municipal specifications and DOT appearance requirements
- Factory-matched frame and grate set — dimensionally paired at the factory; eliminates field fit issues and sourcing mismatches
- In-stock availability — expedited shipping available; critical for fast-turnaround public works and emergency replacement projects, standard 7-10 days
Application Guide
Ideal for:
- Municipal roadway stormwater collection at low points, intersections, and curb transitions
- Parking lot drainage in commercial, institutional, and industrial facilities
- Driveway aprons and shared-access driveways subject to standard truck and delivery vehicle traffic
- DOT, public works, and municipal infrastructure replacement programs
- General contractor drainage packages requiring a compact 12-inch square basin footprint
Not recommended for:
- Airport tarmac, heavy industrial, port environments requiring Extra Heavy Duty or ductile iron specifications above H-20
- Contact us to discuss options.
- Pedestrian or cyclist-accessible locations where ADA-compliant grate geometry is required check out our where ADA compliancy is a must 12″ Heavy Duty Catch Basin Frame and Grate ADA
Grate Pattern Options — 12 Inch
The 12″ catch basin is available in three grate configurations. Select the pattern that matches your project specification or municipal standard.
Round-hole pattern — this page. Standard municipal configuration for roadway and general drainage applications.
12″ Heavy Duty Catch Basin Frame and Grate with Square Holes Square-hole pattern — 12″ Heavy Duty Catch Basin Frame and Grate with Square Holes. Larger open area per aperture, specified in select municipal standards and drainage applications where larger debris passage is acceptable.
12″ Heavy Duty Catch Basin Frame and Grate ADA – ADA-compliant pattern — 12″ Heavy Duty Catch Basin Frame and Grate ADA. Bicycle-safe slot geometry meeting ADA and PROWAG requirements for pedestrian and cyclist-accessible zones. – special order for both designations
Need a Different Basin Size?
Amercast stocks the complete range of heavy duty catch basin frame and grate sizes. If the 12-inch unit does not match your structure or drainage area requirements, select from the full lineup
14″ Heavy Duty Catch Basin Frame and Grate — mid-range footprint with greater hydraulic inlet area; no basin structure upsizing required.
16” HD CB F/G— high-capacity mid-size basin for commercial and roadway drainage.
18″ Heavy Duty Catch Basin Frame and Grate — large-basin applications for high-flow drainage zones.
24″ Heavy Duty Catch Basin Frame and Grate — maximum-capacity basin for heavy-volume municipal and commercial installations.
Browse the complete Catch Basin Frames and Grates catalog, or explore related drainage products for your project:
Inlet Frames and Grates— curb and combination inlet solutions.
Manhole Frames and Covers — access and maintenance structures.
Manhole Frames and Grates — ventilated cover options for sewer and utility structures.
About Amercast
American Cast Iron Products, Inc. has served the sewer, waterworks, and construction industries for over 27 years. With more than 1,000 specifications stocked across manhole covers, catch basins, inlet grates, valve boxes, trench drains, and more, Amercast is the single-source supplier trusted by contractors and engineers throughout the Northeast. We carry both domestic and import grey iron and ductile iron castings, giving you flexible options for Buy American compliance and project budget requirements.
Questions about specifications, availability, or project submittals? Call 516-624-8543
Request a Quote — same-day response for in-stock items.
Need more CFS/GPM and open flow rate area, take a look at the next size up – A little bit bigger, a little bit wider: 14″ Heavy Duty Catch Basin Frame and Grate
Take a deeper dive on the ACIP #1232 12” x 12” designed for municipal stormwater drainage applications requiring dependable strength, long service life, and traffic-rated performance. Manufactured from durable gray iron and engineered for H-20 rated loading conditions, this assembly is ideal for roadways, parking lots, commercial developments, industrial facilities, and public infrastructure projects.
Built to withstand demanding traffic-bearing environments, this heavy-duty catch basin grate assembly provides efficient stormwater runoff collection while maintaining structural integrity under repeated vehicular loading. The precision-cast frame and grate design delivers a secure fit, durability, and long-term performance for municipal and commercial drainage systems.
Amercast catch basin frames and grates are manufactured for municipalities, contractors, engineers, utility authorities, and public works departments seeking reliable cast iron drainage products for infrastructure applications.
Features & Benefits
- Heavy-duty gray iron construction for long-term durability
- H-20 rated for traffic-bearing roadway and municipal applications
- Designed for stormwater drainage and runoff collection systems
- Suitable for municipal, commercial, industrial, and roadway installations
- Precision-cast frame and grate assembly for secure fit and stability
- Excellent wear resistance and structural integrity
- Ideal for parking lots, curbs, streetscapes, utility corridors, and drainage infrastructure
- Available with custom markings and municipal identification upon request
Applications
This 12” x 12” catch basin frame and grate assembly is commonly used in:
- Municipal stormwater drainage systems
- Parking lot drainage
- Commercial site drainage
- Roadway runoff collection
- Industrial drainage infrastructure
- Sidewalk and streetscape drainage
- Utility and public works projects
- Storm sewer systems
Product Specifications
| Specification | Details |
| Product Type | Catch Basin Frame & Grate |
| Size | 12” x 12” |
| Material | Gray Iron |
| Load Rating | H-20 Rated |
| Application | Stormwater Drainage |
| Installation Areas | Municipal, Commercial, Industrial |
| Frame Type | Heavy Duty Catch Basin Frame |
| Grate Style | Drainage Grate |
| Traffic Rating | Vehicular Traffic Rated |
Why Choose Gray Iron Catch Basin Grates?
Gray iron remains one of the most widely specified materials for municipal drainage castings because of its strength, wear resistance, vibration dampening properties, and reliable long-term infrastructure performance.
For stormwater systems requiring dependable structural integrity and cost-effective performance, gray iron catch basin grates provide an ideal combination of durability, serviceability, and long service life in demanding roadway and municipal environments.
Related Products
- Catch Basin Frames & Grates
- Inlet Frames & Grates
- Manhole Frames & Covers
- Heavy Duty Drainage Grates
- ADA Compliant Drainage Grates
- Ductile Iron Catch Basin Grates
- Combination Inlet Frames & Grates
Frequently Asked Questions
What is an H-20 rated catch basin grate?
An H-20 rated catch basin grate is designed for traffic-bearing applications commonly found in roadways, parking lots, municipal streets, and commercial infrastructure environments.
What material is used in this catch basin frame and grate?
This assembly is manufactured from heavy-duty gray iron for durability, strength, and long-term drainage performance.
Where are heavy-duty catch basin grates commonly installed?
These drainage grates are commonly installed in municipal streets, parking lots, industrial facilities, commercial developments, and stormwater drainage systems.
What are the benefits of gray iron drainage castings?
Gray iron provides excellent compressive strength, wear resistance, vibration dampening, and dependable long-term performance in roadway and stormwater applications.
Can this catch basin grate be customized?
Custom logos, municipal markings, lettering, and project-specific casting modifications may be available upon request.
Looking for specification-ready drainage castings for municipal or commercial projects? Contact Amercast for pricing, lead times, custom casting options, and bulk order support for catch basin frames, drainage grates, inlet assemblies, and municipal infrastructure castings.
Request a Quote Today:
516-624-8543
