How to Fix Sagging Patio Chairs

Last updated on October 12th, 2022

Knowing how to fix sagging patio chairs could save you lots of money you would have spent on replacing or repairing a slumped patio seat. Because outdoor furniture often lives outside, they are exposed to the elements, which often makes them wear quicker. 

To fix one of these, replace the saggy old cushion inserts with new ones from Amazon or your local patio fabric shop. If the frame is the problem, you can buy and install customizable saggy furniture support or install fitted plywood beneath the affected cushions. If your patio chair consists of mesh slings or vinyl straps, you will have to buy and replace the worn material with new ones to restore support. 

List of the things you will need for this exercise 

You might have or need one or more items in your list that are not identical to what we have here—that is perfectly okay. It will largely depend on the patio furniture you have and how you choose to approach the repair. 

  • Track saw
  • Tape for taking measurements 
  • Half-inch plywood sheet.
  • New vinyl straps
  • Pieces of cloth
  • Centipede portable work stand
  • Chalk line
  • Palm sander
  • New foam for a cushioned chair 
  • Scissors
  • Screws
  • Drilling machine 
  • Utility knife 

How to fix sagging patio chairs

How you fix your sagging patio seats will depend on whether they have cushions or not and whether the cushions or the support beneath them are sagging. 

Outdoor seats come in a wide variety of materials, including mesh slings, vinyl straps, and wooden slats. Often, these can have cushions for comfort or remain bare depending on their purpose and owner’s preference. 

This tutorial will focus on how to fix sagging patio chairs made of vinyl straps and mesh slings; these are the types that are most notorious for sagging over time.

Also, we will further look at how to fix sagging patio chairs when cushions are involved. 

How to fix a sagging chair cushion 

For a cushioned patio chair, the cushion is likely to be the first component of the chair to deteriorate. This component will be doing much of the work each time the chair is in use, being the primary point of contact with the user’s body day.

Thankfully, slumped cushions are easy to repair. Let us dive right in with a step-by-step approach. 

Steps to follow 

Step 1: Remove the foam inside the cushion cover. If the cushion has a zip, your work will be more straightforward: unzip the cover to access the material inside. 

If the cushion has stitching, you have a little more work to do. Start by removing the stitches one by one to create an opening on one end of the cover. Once done, pull out the insert from that opening. 

Step 2: Use the tape to measure the inserts and cut out pieces of the same size(s) from the new foam. 

There are two options for restoring your cushions here. The first option is to dispose of the saggy old insert and replace it with a new one. This is the option if the foam is thick enough to match the original size of the now old piece, filling up the cushion case.

The other option is to attach the old and new insert using a spray adhesive to create a thicker, firmer insert for your restored cushion. So, assess your items and decide which alternative will work for your case. 

Step 3: Once you have inserted the new piece in the case, zip it up to finish the job if it is a zipper-type. 

For a stitched cushion, use your machine to sew it right back and replace it on the patio chair. 

Of course, this would be the procedure if you have foam-type cushions. If your pillows are made of fiberfill stuffing, you would have to buy the same Polyester fiberfill and stuff it into the cushion cover after unzipping or unstitching the cushion.

After that, you would sew it or re-zip it before placing it back on the outdoor chair. In other words, the steps remain the same, except you will be using polyester fiberfill in place of foam. 

How to fix sagging patio chairs with plywood 

There are times when the cushion will be in perfect shape, yet your cushioned chair is sagging. When this happens, the culprit is usually the frame under your pillows. 

One quick fix for this problem is buying and fitting specialized supports under the slouchy cushions and seeing the problem gone just like that. Often, the supports have a customizable fit that you can tweak to go with any chair. 

Also, they are designed with interlocking panels for easy assembly, so you will not need any special skills to use them.  

The only downside of this option is that you will have to dispense with a bit of cash to get the supports. 

A more cost-effective option is to fix the underlying issue through a custom approach by installing fitted plywood beneath the affected cushions. Here is the simple procedure to get the job done in a matter of minutes. 

Step 1: Begin by removing the cushion from the chair and taking off the seat from the furniture if they are removable frames. Take the measurements of the seat frames to establish how much plywood you will need to cover each seat frame.

Step 2: Second, you want to measure the plywood area that you will cut off for use. To do this, you can create a paper template of each seat and transfer it to the plywood or simply lay each seat frame onto the plywood sheet and mark it around. 

Once you are done with the markings, use a circular saw or track saw (whichever you are more comfortable with) to cut the plywood to the respective seat sizes. 

Pay attention to each of the measurements while cutting the plywood. In this situation, it is safer to err on the side of caution than damage the plywood sheet and be forced to buy another one at an additional cost. 

Bonus tip

For safe cutting, consider putting a piece of rigid foam insulation under the plywood sheet while making the cuts. The depth of your saw’s blade should go only slightly past the lumber and barely touching the insulation. 

Cutting the plywood sheet on top of the foam insulation this way helps protect your work surface from the track saw blade. Also, the insulation provides the lumber with the much-needed support while you cut. 

Step 3: Prepare the seat for the plywood by removing any webbing that may be there initially for support. Cut off the webbing in the middle and proceed to remove it from the frame. 

Step 4: Use a jigsaw to cut off any corners to the exact shape of your seat frame. Use a sander to smoothen out the cut sections to the desired feel. Sand every rough edge and every other surface of the plywood to get rid of any splinters.

Step 5: Treat the sanded plywood with a primer or paint. This is especially essential if it will be subjected to the weather elements that can easily cause molds, mildew, and rot to untreated wood. The sealing treatment will also guarantee the longevity of your plywood.

Step 6: Secure the plywood to the frame by driving a screw through the cut plywood at each of the frame’s corners and any cross supports. Take care not to keep driving the screw when its head has reached on top of the seat frame.

Step 7: Now, it is time to set the plywood in place. Place the frames with the plywood back into the furniture and return the cushions over them. Voila, your seat has a new breath of life. 

For a seat with a fixed (non-removable) frame, you would skip the screwing bit. Take the measurements and prepare the plywood as we have indicated, then simply place the plywood directly onto the seat beneath the cushions.

How to repair a vinyl chair

Most vinyl chairs go along with durable Sunbrella cushions and pillows. When it becomes saggy, the most likely component to fix is the support comprised of the vinyl straps.

This is easy repair work, but it will require a little patience because you must fix one strap at a time, making the task repetitive. 

Once you have your new vinyl straps in place, you can get to work. 

Step 1: Remove the saggy old vinyl straps by cutting each of them in the middle and unwrapping the frame on each end. 

There will be a peg fastening the straps onto the frame on each end; proceed to free the old straps by removing each peg inserted in the holes on these frames. 

Step 2: Using a cloth measuring tape, measure the distance from hole to hole on the chair frame. Wrap the measuring tape around the frame exactly as the vinyl replacement strap will be installed. 

This will be the hole-to-hole measurement used to determine the cut size. So, start your measurement at the hole where you removed the peg and end it on the corresponding spot on the frame’s opposite side. 

Still, it is best to start by cutting a piece of strap and putting it on the chair to see how it fits. With that, you will know if you need to make any adjustments before going all-in with the entire bunch of straps. 

Step 3: Once you have determined the correct length for each strap, use a measuring tape and a pair of scissors to cut the straps off the roll at the desired size. 

Step 4: Drill holes at the ends of both sides of each vinyl strap using a handheld drilling machine of your choice. Keep each hole about half an inch away from the edge. Then, use the scissors to trip the corners of both sides of the vinyl straps.

Step 5: Insert the vinyl straps into boiling water and leave them in there to soak for a few minutes. This will loosen them up and allow them to stretch when pulled during the fitting process.

Step 6: Use a pair of tongs to remove a strap from the boiling water and immediately dry it with a clean rag or towel. Then, use your thumb pressure to insert a peg through the vinyl strap and attach it to a hole on the chair frame. 

Insert the rivet through the strap and into the hole of the underside of the chair frame. Ideally, this should be the same hole where you removed the peg while taking out the old vinyl strap. 

Step 7: Next, wrap the strap around the metal frame, preferably twice. Then, use one hand to pull the strap across to the other side while holding down the chair frame. 

Without letting go of the chair frame, hold it in place with one hand and use the other hand to make a double wrap of the strap around the metal, just like on the other end of the strap. Be careful to avoid covering the hole while wrapping.

You will need to stretch out the strap to its maximum length to make it taut and reach the hole for fastening. 

Step 8: After completing the double wrap, use another rivet to attach the strap to the hole on the frame. Notice that this other end of the vinyl strap should end up on the inside of the frame with the hole punched on the strap corresponding with that on the metal frame.

At this point, the fastened strap will be misaligned. To correct that, carefully slide the vinyl replacement strap over itself around the top of the rivet and adjust as necessary to achieve the correct alignment. 

To this end, you will have installed only a single vinyl strap. To complete the job, you will need to repeat the process for the rest of the straps still in hot water.

How to fix sagging patio chairs made of mesh sling 

This group of outdoor chairs comes with mesh fabric that can get pretty slack from use over time. If you have these, you may have to repair them from time to time if you want to get the most out of them. 

To fix the loose seat, here are the steps you need to follow. 

Step 1: Start by measuring the chair for its width, length, and curvature.

Step 2: Get yourself a new sling based on the measurements. You can order these slings online on Amazon or acquire one from a patio fabric shop near you.

Step 3: Once you have your new sling handy, cut it according to the measurements you just took. 

Step 4: Remove the old sling from the chair, ideally by sliding half of the chair’s sling from the rail after removing the bolts and freeing the rail. Also, locate the spreader bar and remove it as well. 

If you wish to repaint any part of the chair, consider doing it now before proceeding to the next steps. You may also want to repair the spreader bar at this point if it needs repairing. 

Step 5: Separate the rail from the patio furniture and insert the nylon rod of the sling in the other rail. Ensure the sling’s hem side faces the rear of the chair.

Step 6: Slide the rail you removed back into its place and connect the rod that you detached from the opposite side of the frame. Next, return the spreader bar into its place, bending it slightly for better fitting if necessary.

Step 7: Finally, cut any excess rod to fit your chair using a wire cutter, and cover the rods with the end caps. 


I hope you enjoyed this tutorial and that it helped you fix your sagging patio chairs. We will be delighted to hear any observations and comments in the comments section below. Feel free to share.