Hello there! The information from the sources you provided was a bit sparse, so I'll give you a friendly and comprehensive guide based on general know-how for tackling those saggy sofa cushions.
It's a super common problem when a beloved sofa starts to feel more like a sinkhole than a cozy spot. The fix usually comes down to addressing one of two things: the filling inside the cushions or the support system underneath them.
First, let's look at the cushions themselves. If they've gone flat, the best solution is to add new life to their stuffing. If your cushion covers have zippers, this is a very manageable DIY project. You can buy high-density foam, often cut to the exact size you need, from a fabric or upholstery store. For a plusher feel and a smooth, rounded look, try wrapping the new foam core in a layer of polyester batting before stuffing it back into the cover. This simple extra step can make a huge difference.
If the cushions seem fine but you're still sinking, the problem might be the support structure of the sofa itself. A fantastic and easy fix for this is to add a support board. You can use a thin piece of plywood cut to fit the seating area of your sofa frame and place it directly underneath the cushions. This creates a firm, even base and instantly stops the sag. There are also specially designed, foldable sofa support products you can buy online that achieve the same result.
For a quick, no-cost tune-up, simply fluffing your cushions regularly can help. If you can, unzip the covers and rearrange the filling inside to break up compacted areas. Don't forget to flip and rotate your cushions every week or so to ensure they wear down evenly. With a little effort, you can bring your sofa back to its former glory
