Square Flat Grates

Square Flat Grates

Product Files
Product Description

This grate is a rugged square, flat grate designed to be used in conjunction with a catch basin.  It has large opening slots for maximum flow while still preventing large debris from entering the drainage system. Capable of withstanding auto and light truck traffic at speeds under 20 mph. 

When installed, the grate surface is flush with the surrounding area.  For safety reasons and to prevent vandalism or theft the grate has two holes enabling it to be screwed onto the basin. Available in 9", 12" and 18" sizes.

  • Manufactured from structurally foamed High Density Polyethylene (HDPE).
  • UV stabilized to protect from sun degradation.
  • Available in green, black, sand and grey.
  • Textured anti-skid surface.
  • Load rated for autos and light trucks at speed less than 20 mph.
  • Includes two bolt holes to secure to basin (use # 6 x 1.5" flat Phillips head stainless screws).
  • ADA compliant.
  • Made in the USA.

This square flat grate fits onto a catch basin and is used for medium sized areas of grass, flower beds, decks, driveways, golf courses, medians, etc. The function of the catch basin is to collect sediment in it's sump area and not allow this sediment to enter and plug the drainage pipe.  Grate is designed to withstand light duty, low speed vehicular traffic including autos, light trucks, golf carts, etc.

9 inch Grate

Dimensions:8.90" length x 8.90" width x 1.15" height
Weight: 0.90 lbs.
Open Area:38 sq in
Slot Width:3/8"
Flow Rating:50 GPM
Max Load:2,000 lbs. *

12 inch Grate

Dimensions:11.75" length x 11.75" width x 1.15" height
Weight:1.70 lbs.
Open Area:53 sq in
Slot Width:7/16"
Flow Rating:70 GPM
Max Load:3,000 lbs. *

18 inch Grate

Dimensions:16.70" length x 16.70" width x 2.15" height
Weight:5.40 lbs.
Open Area:92 sq in
Slot Width:15/32"
Flow Rating:120 GPM
Max Load:4,000 lbs. *

*(Maximum load based on weight uniformly applied across grate surface.)

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