When your office chair keeps sinking, it can be both annoying and frustrating, not to mention incredibly uncomfortable. Such a chair can significantly decrease your productivity at work due to excessive fatigue and discomfort. If you’re a tall person, you may have it even worse.
A sinking office chair is an issue that requires immediate attention. This is not something that anyone should have to deal with.
The good news is that you don’t need to replace the entire chair or call a professional to fix it for you.
A few simple DIY tricks can help you fix the problem and adjust the chair to the desired height so you can make your office space as comfortable as possible.
Before we discuss how to fix a sinking office chair, let’s talk about the main reason why office chairs sink over time:
Why Does my Office Chair Keep Sinking?
If you notice that your new or old office chair has started sinking for no specific reason, it doesn’t necessarily mean that it’s completely damaged. The simple reason for this is that the chair has lost its lifting functionality. Here is why.
You see, office chairs typically use a pneumatic cylinder that controls the height of the chair through pressurized air. It is the part of the chair that connects the base to the seat.
A properly working cylinder allows you to easily adjust the height of the chair up and down. Inside it is Nitrogen Gas. Whenever you try to adjust the chair using the lever, the nitrogen gas inside the chambers switches, thus allowing you to adjust it up and down.
However, the cylinders often fail after being in use for several years as the seals are usually too worn out and damaged to maintain enough pressure. The valve seal in the cylinder eventually starts to leak. These parts become worn out, which causes office chairs to keep sinking when sat on.
How Do You Fix an Office Chair that Won’t Stay Up? (Step-by-Step Guide)
You have three options to fix a sinking office chair that keeps sinking. They include:
- Using a Hose Clamp
- Installing a PVC Pipe
- Replacing the pneumatic cylinder
Let’s discuss each one of these solutions:
1. Use a Hose Clamp (Jubilee Clamp)
If your computer chair keeps sinking, one of the most common fixes for this is using a hose clamp.
Also known as a hose clip, hose lock, or Jubilee Clamp, a hose clamp is a device that is commonly used to attach and seal hose pipes onto a fitting such as a barb or nipple.
When tightened around a chair cylinder, it’s perfectly capable of supporting a large amount of weight- typically from 135lbs upwards.
The load capacity may depend on the company from which the clamp is made from.
In this case, you will require a hose clamp that is at least ¾ inches in diameter. You can get it from your local hardware store.
Here is the procedure to follow for the hose clamp method:
- Slide the plastic skirt either upwards or downwards until you see the metal pneumatic cylinder underneath it.
- The next step is setting the office chair seat to the right height. This step is crucial because after attaching the Jubilee Clip, you will not be able to adjust the height again. To ensure you adjust to the perfect level, make sure that the chair seat is in level with your knees while standing. If the plastic skirt fully covers the metal cylinder when you set it to your preferred height, you may need to remove it to make it accessible. To remove the plastic skirt, turn the chair upside down and then push the retaining clip located at the base with a screwdriver. Next, remove the wheels and then slide off the skirt, and then put the wheels back on.
- With the plastic skirt out of place, now it’s time to attach the hose clamp around the cylinder. But first, you need to wrap a few strips of duct tape around the cylinder in order to enhance the grip of the clamp. The metal cylinder is very smooth and may not provide a grip strong enough to hold the chair up, especially when weight is put on it. A few layers of duct tape strips are enough. If covered with grease, be sure to wipe it off before applying the tape
- Next, loosen the screw on the clamp and then pull out the belt end. Wrap the clamp around the cylinder at the topmost part and then tighten the clamp screw. Make sure it’s fastened tightly to ensure a stronger hold
- With the hose clamp in place, test the chair by sitting on it. If the chair doesn’t slide past the clamp, then you’re good to go. If it slides off, you can wrap a few strips of rubber near the clamp to ensure a stronger grip
If this method doesn’t work, you can try the PVC Pipe method explained below.
2. PVC Pipe Method
Another common fix for a sinking office chair is using a PVC pipe that is roughly the same diameter as the metallic cylinder or slightly larger. Most PVC pipes with a diameter of 1.5 inches or 3.8 cm will work well in most office chair models. You can also measure the cylinder.
However, you’ll still need to measure the diameter of your chair’s cylinder to ensure you purchase a perfect fit.
You also need to measure the length of the exposed metallic gas cylinder after setting the chair to the preferred height. If the plastic skirt covers a large part of the cylinder after setting the preferred height, you can slide it over it until it’s exposed.
- After determining the diameter, head over to your local store and purchase enough PVC pipe that will fit the measured length of the cylinder.
- Next, cut the pipe lengthwise with a saw, but only on one side.
- Attach the slit pipe into the cylinder, by gently opening it at the cut and pressing it onto the cylinder. It should help prevent the office chair from sinking. If the chair height is too low, you can add another slit PVC pipe until you achieve the desired length.
- Next, try to adjust the seat height. It should now stay in place. Remember you can always add more pipes until the perfect height level is achieved.
If this still doesn’t work, you’ll need to replace the pneumatic cylinder
Safety Precaution: Wear a mask or respirator when sawing the PVC pipe as the plastic particles can be dangerous when inhaled.
3. Replace the Pneumatic Cylinder
This should be your last resort if the above methods fail to work.
If your chair is already old, there is a high chance that using a hose clamp and PVC pipe may not work since the cylinder is already worn out and damaged.
Furthermore, these two methods are only temporary fixes. A more permanent fix is replacing the entire cylinder.
Most office chair cylinder replacements are reasonably priced. However, if yours is a very cheap chair, probably in the $60 range, the best decision would be to purchase another chair since the price of most cylinders is close to that of a new chair in this price range.
The best hydraulic or pneumatic piston in the market is the Office Oasis Store Heavy Duty Gas Lift Hydraulic/Pneumatic Piston. It’s a universal standard size that will fit at least 95% of all office chairs.
It’s also perfectly capable of supporting up to 1000lbs without any issues.
It’s a heavy-duty cylinder that helps fix your sinking office chair problem instead of spending more money getting a brand new replacement.
It’s also the only replacement cylinder that comes with a removal tool so you won’t have to waste time trying to remove the old one with the wrong tools.
Inside the package are things like a removal tool, a step-by-step installation guide, and gloves. It comes with the manufacturer’s money-back guarantee so even if it doesn’t fit your specific chair model, you can always return it for a full refund or replacement.
To replace the pneumatic/hydraulic cylinder, carefully follow the manufacturer’s instructions and use the removal tool to properly and quickly detach the old one.
This is a simple DIY fix so you don’t need to call in a professional to do it for you.
How Do You Fix a Hydraulic Sinking Office Chair?
Many office chairs use the pneumatic system to allow for easy height adjustment as well as a 360 degrees swivel.
The system uses compressible gases, unlike the hydraulic system which uses incompressible liquids to operate. Pneumatic chairs are preferred for their cleaner technology as unlike hydraulic pump systems, there is no risk of hydraulic liquid or oil leakage. 
Usually, hydraulic systems are commonly found in salons or barber chairs. The chairs feature a hydraulic pump that allows the chair’s height to be easily adjusted and even swivel up to 360 degrees.
Fixing a hydraulic sinking chair is easy. Simply cleaning the hydraulic cylinder and oiling the joints and other external mechanisms will help it function properly once again.
If none of these fix the problem, you might want to consider getting a replacement. The Office Oasis Store Heavy Duty Gas Lift Hydraulic/Pneumatic Piston also works great for hydraulic desk chairs.
When disassembling the pump, make sure you place a newspaper or absorbent rag beneath to avoid your carpet from getting stained by the hydraulic fluid.
Computer Office Chair Keeps Sinking – Bottom Line
An office chair that doesn’t stay up even when no one is sitting on it must be fixed as fast as possible, otherwise, the discomfort would become too much and eventually turn into chronic pain.
Luckily, fixing a chair that keeps sinking is not rocket science. With the right tools, you should get the chair back up to the desired height. And if the fixes fail to work, you can always install a new cylinder and have the desk chair working like it’s brand new!