Heavy Duty Office Chairs

Heavy Duty Office Chairs for Control Rooms and larger individuals

Our range of ergonomic Heavy-Duty Office chairs is specifically adapted for Big & Tall people as well as 24/7 use in control rooms and call centres. Whether you require a mesh-back or fully upholstered chair, these chairs are designed to be durable and withstand extreme 24/7 usage.

What is a Heavy Duty Office Chair?

Our heavy duty office chairs are designed and built to support individuals who require a sturdy and durable seating solution. Typically, these chairs are used for specialist applications like call-centres and control rooms that operate 24/7, or for individuals who are larger in size.

Our heavy-duty chairs are meticulously crafted using robust materials, including reinforced frames, upgraded gas lifters, and high-quality swivel mechanisms, ensuring they can endure heavier weights and extended use while preserving both comfort and structural integrity.

Take, for instance, the demands of a 24/7 control room or a bustling call center, where office chairs see continuous usage throughout multiple shifts. On the other hand, a larger individual, such as someone with a weight of 130kg or more, requires an office chair that offers both increased size and enhanced strength to adequately support their frame. In such scenarios, standard office chairs, designed for a maximum weight capacity of 120kg and an average 8-hour workday, fall short, making a heavy duty chair the clear and practical choice.

“When a standard office chair is deployed in a heavy duty environment, two common outcomes typically emerge. Either the chair’s performance and longevity suffer, or it might unexpectedly fail, potentially resulting in injury.”

Components used for Heavy Duty Office Chairs

1. The Base Set 

a. Castors or wheels

Our heavy duty office chairs all have large diameter castors as they have a higher load carrying capacity.

For example, 60mm diameter castors have a higher carrying capacity than 50mm ones and they are more manoeuvrable. 

heavy duty chairs

b. The 5-Star base

5-Star bases are made either from aluminiumglass reinforced nylon, or formed steel tubing.

    • Aluminium bases have a very high weight carrying capacity and can be recycled. For this reason, most of our heavy duty office chairs have aluminium 5-star bases. 
    • Bases made from nylon with glass fibre reinforcing have become extremely popular. With the correct design structure, quality nylon, and a 30% glass fibre reinforcement filling, nylon bases are a good choice for heavy duty office chairs. These bases provide excellent strength and are flexible enough to move easily over slightly uneven floors. 
    • Bases welded together from steel tubing are known to fail along weld lines. Such failures usually occur without warning and may result in injury. For this reason, none of our heavy duty chairs have a welded steel base.

c. Gas lifter

The gas lifter allows you to raise and lower the seat height of the chair. It also acts as a ‘damper’ to cushion the impact when you first sit down. Gas lifters should be manufactured in accordance with a specific international design standard, for example DIN EN 16955-2017. If they are, they will carry the applicable mark or logo as well as a Class Rating. Our heavy duty chairs have a Class 4 gas lifter which has a higher load rating than the standard Class 3 found on most office chairs.

2. The swivel mechanism on heavy duty office chairs

The mechanism enables you to adjust the movement of the seat and backrest. Adjustments include the angle of the seat and backrest, the depth of the seat (important for taller individuals), the seat height, and the tilt tension.  

The strength of the office chair mechanism in a heavy duty environment is vital. To ensure that the mechanism is suitable, all our heavy duty chairs have mechanisms that have been strength tested by SABS or BIFMA.

The mechanism on Karo’s Heathrow chair was tested and certified by the SABS in 2005. The procedure involved cycling a weight of 200kg on the mechanism 300 000 times!

heavy duty mechanism
Heathrow Heavy Duty Office Chair

3. The Seat on heavy duty office chairs

Seats for chairs used in a 24/7 environment need to be strengthened to “carry the load”. Normal or standard office chair seats are not designed for a heavy duty application. 

Common materials used for the seat base are plywood, polypropylene or nylon. A seat suitable for a heavy duty chair needs thicker plywood with more laminations. Heavy duty seats made from polypropylene or nylon require additional structural webs or steel reinforcement. The OrthoGrande XXL chair has an extra large seat and backrest to accommodate people with a larger frame.

4. The Backrest of heavy duty office chairs

For any office chair, the backrest support structure is not as heavily stressed as the seat. Upholstered plywood backrests do not normally require additional reinforcement, while polypropylene shells typically have standard web reinforcements. If the chair has a mesh backrest like the Alya and Firefly, the supporting frame should be made of a good quality, glass fibre reinforced nylon. Other plastics are simply not strong enough for heavy duty applications.

When do you need a Heavy Duty Office Chair?

Heavy duty office chairs are the preferred choice for:

    • 24/7 applications like a call centres or control rooms, or
    • Larger individuals who require a chair that can support their frame.
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