How to Replace 1″ Thick Grates

1″ Grates – No Longer Heavy Duty

Architects once specified 1-inch thick cast or ductile iron grates for loading docks, warehouses and industrial areas. These were typically installed within an angle-iron frame by contractors using the old wooden box form method. In today’s industry, the 1″ thick grates are no longer considered “Heavy-Duty” and drainage systems are typically modular.

With expected loads increasing over time, the 1″ thick grate became rare, a holdover from decades past. New construction projects now specify newer “standard” sizes, such as ¾” thick grates that are often paired with a strengthening frame to increase the Load Class. Also, foundries have recognized this shift and started offering 1-1/2” to 2″ thick heavy-duty grates that require no extra reinforcement. However, they are often still paired with angle iron or rails that help protect the preformed cement channels.

How do I replace 1” thick grates?

It is very important to clarify the needs of your project in order to specify the correct grating. Improper system selection, incorrect grates, inaccurate installations and poor maintenance are among the most common reasons why drainage systems fail.

There are several options available when considering replacing your current 1″ thick grates. The suitability of each is based on the application, what type of traffic will be moving over the grates and if they will be exposed to any chemicals.

Fiberglass Grates

Replace with Fiberglass

Already a popular replacement choice, fiberglass grates have several things going for them.

  • Chemical/rust resistant
  • Load bearing capability
  • Low scrap value
  • Custom Sizes Available

Fiberglass grates are durable, rust-proof and usually not stolen for the scrap value. They come in several patterns and load classes, so ask an expert before replacing anything. However, in the right circumstances, a 1-inch fiberglass grate will make a suitable replacement for aged cast iron.

Replace with Foundry Grates

Though used for a variety of applications, cast iron foundry grates are intended for heavy load situations and most of the foundries have transitioned into providing 1-1/2″ to 2″ thick grates with a variety of widths. Custom grates are also available when a project calls for unique sizes, specific load ratings or a solid cover. This type of grating is known for its strength and durability.

Steel Bar grating

Replace with Steel Bar Grates

As drain cover replacements go, steel bar grates may be the answer to your project sizing issues. They have the ability to be 1″ thick and are available in custom widths, lengths and styles. Wider grates require more bearing bars to keep the same level of strength as narrower varieties, making it important to account for the traffic crossing over your drain when deciding if this is the right solution. If in doubt, ask an expert.

Install a New Drainage System

As a last resort, often times a new drainage system is required. Sometimes this is the option that makes the most sense, but retrofitting comes with its own challenges. These challenges are often financial in nature, as a completely new and modern trench drain system can be expensive, depending on the type of application and footage.

When should I just reinstall the drain?

  • Fiberglass or bar grating won’t be strong enough
  • Foundry grates don’t come in that width
  • The channel or surrounding concrete shows damage
  • The current system isn’t supporting the water runoff needs

If any or all of these criteria are met, you may be better off reinstalling the drain with a modern system that meets new construction expectations.

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