My mom claims that by me sitting on my sofa, I am wearing it out. Now, of course this puts wear on it. But does this put in actually wear on it? Like does it decrease the longevity of the couch? If you have any sources you can site, that would be great.
Well, of course, sitting on it will eventually wear it out. Friction on the fabric wears it thin (and eventually, out), sitting on the cushions flatten them, etc. If you go to any house where people have a front room (that is seldom used) and a family room that is always used, which sofa looks newer? Using slip-covers will keep a sofa looking newer longer, by protecting the fabric from wear, stains, and fading, but cannot protect cushions from getting flattened. If use didn't eventually wear furniture out, there wouldn't be much need to replace it, and used furniture wouldn't look used.
Ask your mom if the clear plastic furniture covers from the 1970's would help out?
It was purchased to use for that purpose. It will eventually need to be replaced, so if you're not going to use it for it's intended purpose, remove it and replace it with a pool table. They last longer than a couch will.
Define Sitting. Slamming onto the sofa, putting your feet (in shoes) up and your heels digging into the cushions will put *excessive* wear on the couch. Sitting upright on the sofa with both feet on the ground, dead-still with only a small (empty) tea-cup in one hand (little finger out) and the saucer in the other will put *minimum* wear on it. If one weighs 200+ pounds, add an additional factor to the above. If one weighs 300+ pounds, yet more and so on. Normal wear is something in between.