ABT, Inc. • PO Box 837 • 259 Murdock Road • Troutman, NC 28166
(800) 438-6057 • (704) 528-9806 • Fax: (704) 528-5478

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Grating and Concreting

Grating Installation Prior to Concreting

Note: The grates must be in place prior to concreting since they aid in maintaining alignment and joint smoothness.

Wrap the grates in plastic or masking tape and place them in the channel grate lip so that they span the channel joints as shown below or place the grates upside down. Locking the grates in place will help secure channel alignment. A 1/16" thick shim placed between the grate and the upright edge of the channel grate lip will ensure the grate will properly fit after concreting.

Grating prior to concreting

Alternate method

Alternate to Grating Installation Prior to Concreting

As an alternate to placing covered gratings in the channel prior to concreting, strips of 3/4" thick plywood "ripped" to 4-15/16" wide can be used. Since this width is slightly wider than the grate itself, it is not necessary to place shims in the upright edge of the channel/sidewall grate lip as before. The width of the plywood strips must not be less than the width of the grates. As with the gratings, the plywood strips must also span the channels joints. Thses strips provide a complete cover for the trench during concreting, thus eliminating having to clean concrete spillage out of the trench before final grate installation.

The plywood strips may be oiled and reused on future installations.