A trench drain system is only as effective as the grate that covers it. The grate not only protects the channel and supports traffic but also determines how much water can enter the system—and how well it resists wear, corrosion, and load impact.
With dozens of grate options available, choosing the right one depends on the application, load class, environment, and aesthetic goals. In this guide, we’ll review the top 7 trench drain grate types, explain their strengths, and help you select the best one for your project.
You’ll also find links to our grate product pages, load class charts, and material comparison guides to support your decision.
Why Grate Selection Matters
A trench drain grate serves three primary functions:
- Allows water entry into the channel
- Supports pedestrian and/or vehicular loads
- Protects the underlying drain from clogging or damage
Choosing the wrong grate can lead to cracked surfaces, collapsed systems, trip hazards, and clogged channels. The right grate balances hydraulic performance, structural integrity, and ease of maintenance.
Key Factors in Grate Selection
When comparing trench drain sytems and grates, consider the following:
- Load Class (A15 to F900)
- Material Type (HDPE, cast iron, stainless steel, etc.)
- Opening Style (slotted, perforated, mesh, etc.)
- ADA and Heel-Proof Compliance
- Chemical or Corrosive Exposure
- Ease of Removal and Cleaning
- Visual Aesthetic
Use our trench drain grate selection tool to filter by load, material, and application.
The 7 Most Common Trench Drain Grate Types
1. Slotted Grates
Description: Linear or offset slots spaced evenly across the width of the grate.
Best For:
- Parking lots
- Driveways
- Loading docks
- General commercial use
Benefits:
- High flow rate
- Simple and cost-effective
- Load rated from B125 to D400
Available in galvanized steel, cast iron, and HDPE.
2. Heel-Proof Grates
Description: Grates with openings no wider than ¼ inch to prevent high heels or cane tips from getting caught.
Best For:
- Sidewalks
- Public plazas
- Hotels and retail spaces
- ADA-compliant walkways
Benefits:
- Safety for pedestrians
- ADA and heel-proof compliant
- Available in decorative designs
Often specified in stainless steel or ductile iron. Browse our heel-proof options.
3. Perforated Grates
Description: Flat grates with round, square, or custom holes for drainage.
Best For:
- Food and beverage production
- Clean rooms
- Restaurants and kitchens
Benefits:
- Easy to sanitize
- Minimal debris accumulation
- Aesthetic finish
Primarily manufactured in stainless steel, often used with slot drains.
4. Bar Grates (Welded or Press-Locked)
Description: Parallel bars welded or pressed into a steel or stainless steel frame.
Best For:
- Heavy equipment areas
- Warehouses
- Forklift traffic zones
Benefits:
- High load capacity (D400 to F900)
- Long lifespan under wheel load
- Industrial durability
Available in galvanized steel and stainless configurations.
5. Decorative Grates
Description: Architectural grates with custom patterns—wave, vine, brick, or geometric cuts.
Best For:
- Residential properties
- Public parks and civic buildings
- Pool decks and luxury developments
Benefits:
- Enhances curb appeal
- ADA and heel-proof designs available
- Multiple finish and color options
Explore our decorative grate gallery.
6. HDPE Grates
Description: Lightweight, corrosion-resistant plastic grates.
Best For:
- Light-duty areas
- Residential driveways
- Landscaping and lawn drains
Benefits:
- Easy to install and replace
- UV and chemical resistant
- Cost-effective
Paired with HDPE trench drain channels for a lightweight, all-polymer system.
7. Slot Drain (Grateless)
Description: Narrow linear openings (1/4" to 1") built directly into the drain channel with no separate grate.
Best For:
- Sanitary applications
- Brewery floors
- Walk-in coolers and bottling lines
Benefits:
- Easy to clean
- No removable parts
- CIP and washdown compatible
See stainless slot drains for configurations and outlet options.
Grate Load Ratings Explained
|
Load Class |
Weight Limit |
Example Use |
|
A15 |
3,300 lbs |
Pedestrian use, sidewalks |
|
B125 |
27,500 lbs |
Residential driveways |
|
C250 |
55,000 lbs |
Light commercial vehicles |
|
D400 |
88,000 lbs |
Trucks, parking lots |
|
E600–F900 |
132,000+ lbs |
Airports, industrial sites |
See our load class reference chart for detailed specs.
Matching Grate to Environment and Use Case
|
Application |
Recommended Grate |
|
Driveways |
Slotted (galv. or HDPE) |
|
Sidewalks |
Heel-proof, ADA |
|
Loading Docks |
Ductile iron slotted |
|
Food Plants |
Perforated or slot |
|
Warehouses |
Bar grate |
|
Luxury Homes |
Decorative stainless |
|
Parks |
ADA decorative grates |
|
Pools/Decks |
Plastic or decorative SS |
Maintenance and Cleaning Considerations
Grate design affects how often and how easily drains must be cleaned.
- Bar grates allow large debris through—easy to remove but can clog channel
- Heel-proof and perforated grates limit debris but require regular surface cleaning
- Slot drains have the lowest maintenance but require periodic channel flushing
Use our installation and maintenance guide for cleaning schedules and grate removal best practices.
Cost Comparison by Grate Type
|
Grate Type |
Price Range (Per Linear Foot) |
|
HDPE |
$15–$92 |
|
Galvanized Steel |
$35–$99 |
|
Cast Iron |
$50–$249 |
|
Stainless Steel |
$90–$700 |
|
Decorative |
$110–$250 |
|
Slot (No Grate) |
Integrated into channel pricing |
Get a custom quote using our drainage system pricing calculator.
Summary: Choosing the Right Trench Drain Grate
Selecting the right trench drain grate is just as important as the channel itself. The best choice will balance:
- Hydraulic flow rate, pre sloped our neutral
- Load-bearing capacity
- Environmental exposure
- Safety requirements
- Visual appeal
Whether you’re building a commercial loading dock, luxury pool deck, food facility, or residential driveway, the right grate ensures performance, durability, and safety.
Next Steps
- Explore our complete line of trench drain grates
- Use our grate selector tool to find the right option
- Contact our technical team for engineering support and specification
