Hi,
We got this L-shape couch re-upholstered in/around the COVID lockdowns a couple years ago. We expressly asked for the seating to be redone and really firm but weren't able to test/try before the new material was put on. We like the look but the seating is so soft that we sink right into it and can feel the wood underneath our hamstrings at the front and under our butt at the back.
Is there anything that can be done to firm up the seating without having to go through a full reupholster process? eg, can we go in through the bottom and install slats? open to any ideas as the couch is basically unusable for us since sitting in it causes back pain from the bad posture.