The load rating of a floor drain is a classification associated with that drain that helps engineers and contractors to understand what kind of weight it can be expected to support under ideal conditions. The load class of a drain determines the best environment for that drain.
Drains can be found in all kinds of places from streets to pool decks and from restaurants to factories. Each of these environments will have different kinds of traffic and will require a different load class rating.
What Are the Load Classes for Drains?
There are many load classes for drains. Here are the ones that are most widely used in North American building codes.
ASME A112.6.8/CSA B79.8
This standard outlines the design and performance criteria for trench drains and grate systems utilized within or around non-residential buildings. It references ASME A112.6.3/CSA B79.3 for load test procedures.
ASME A112.6.3/CSA B79.3
This standard details the design and performance requirements for floor drains and area drains that are used within and near building structures. Although this standard covers floor drains and area drains only, the trench drain standard ASME A112.6.8/CSA B79.8, relies on this specification for load test procedures.
DIN EN 1433
This is a European standard for load testing drains. This test standard is one of the few that was specifically written for trench drains.
AASHTO M 306-10
This specification applies to frames, grates, rings, and covers for inlets and manholes used in civil applications, particularly in traffic areas where load bearing is crucial. It also establishes static load test requirements comparable to those previously mentioned.
To meet these certifications, drains should be tested by a certified third party.
How are Drains Load Tested?
Drains are most commonly load tested by placing them in a hydraulic press and applying pressure to a plate placed on the drain until it fails. The maximum pressure the drain can withstand before failure determines which weight class rating it receives.
The DIN standard is the most commonly used today in commercial applications in North America. This standard applies a classification from A to F based on the static load the drain can withstand before failure. Below you will find the specific load classifications for the DIN / EN 1433 standard.
DIN / EN Load Classifications
| Load Class | Test Load (kN) | Test Load (lb) |
|---|---|---|
| A | 15 | 3372 |
| B | 125 | 28101 |
| C | 250 | 56202 |
| D | 400 | 89923 |
| E | 600 | 134885 |
| F | 900 | 202328 |
What load class you require depends on the traffic your drain will face. Will it just have pedestrian traffic like a pool deck drain, or will it have forklift traffic in a warehouse or factory? Both of these places will require drains with different load ratings.
At Global Drain Technologies we generally recommend drains with load class C for pedestrian and light duty vehicle applications. You will find that most of our Landscape Drains are rated class C. We recommend class E rated drains for just about everything else, including regular vehicle traffic and forklift traffic. Our FoodSafe Area Drain and our 10,000 Series Slot Drain are both load class rated E. In the most extreme cases, like a transitway for buses, we recommend a load class E rated drain. Our 11,000 Series Slot Drain is class E rated.
Proper Installation is Key
The test procedure for rating a drain involves encasing it in concrete. The surrounding concrete of the drain is part of how it withstands heavy loads without bending. If you took a drain that wasn’t installed and drove over it, there is a good chance you would bend it. But once the drain is encased in concrete, it becomes part of the floor, making it very strong.
Because the drains rely on concrete to obtain their weight class rating, they need to be properly installed for maximum durability. An improper installation or bad concrete can lead to cracking or bending around even the strongest drain. As shown in the picture above, a proper rebar schedule that follows the manufacturer's installation instructions is necessary for most load class rated drains.
To ensure that the job is done right, it is very important to choose your contractor wisely when installing floor drains. At Global Drain Technologies, we created our Alliance Partner Network to connect skilled contractors with customers and ensure that drains are properly installed.
Elements of a Load Class Rated Drain
While there is no one right way to design a weight class rated drain, there are certain elements that we recommend looking for on drains to determine if they are weight class rated.
- Tested by a certified third party
- Made from stainless steel
- Reinforced in critical areas
- Made to structurally integrate with the floor
These are not the only features that make a weight class rated drain. But if your drain was properly engineered, these factors should have been taken into account. If none of these features are present, it is worth asking what other measures have been taken to ensure the drains are properly load rated.
Where to Buy Load Class Rated Drains
At Global Drain Technologies, we design and manufacture our drains in house. This allows us to perform ongoing research and development as well as a process of continuous improvement on all of our drains. Our drainage designs undergo a process of constant improvement based on real world testing and customer feedback. This allows us to confidently offer some of the most durable drains available anywhere in the world.
If you would like to shop for load class rated drains, you can start with some of our most popular drains, including our area drains, our trench drains and slot drains. To learn more and receive personalized expert advice, please contact our friendly sales staff. Through our right drain right area approach, our staff can assess your situation and recommend one of our existing designs or create a custom design that is unique to your project. Contact us today to learn more.