How to raise a ceiling?

I understand. The trusses are the old finger jointed 'glued' together type that have dried out due to age. Nothing up there, not even plywood that anyone can walk on to make repairs. There's metal then a roof over. Everything has to come down from inside then rebuilt which is where I thought of raising the ceiling. I even thought of bracing the interior wall straight up, then go with a cathedral style on an angle to the outer wall. Just looking for advice from a true carpenter. Thank you.

Okay...this is my $.02. Trusses are no longer constructed in the way you are describing. The parts are now held together by something called ‘Gussets. These are metal plates with fingers (spikes) sticking out. The gusset is placed in position, then the fingers are driven into position. They are made in factories, and trucked to the build location. Now, here’s how this can affect you. You can buy the gussets and hammer them into position to fix your trusses. Now for the tricky part. For you to raise the ceiling you would first need an engineer to come in and assess the job. He will be able to tell you what you can do, and can’t do, as well as how it should be done. The way trusses are put together (abbreviated explanation), you have two boards that form an angle, and face up. These are what give your roof its pitch. There is also a board that runs across from one side to another; it hooks into the two boards I talked about earlier, at the bottom. It is called the ‘tie beam’. This is the board that causes the trouble, but is absolutely necessary. The board is low, which doesn’t leave any room to raise the ceiling. This is also the board that the drywall is screwed into for your ceiling. This board cannot be removed without the whole roofing system collapsing. What can be done though is to install new tie beams on all the trusses higher up the truss. This is where the engineer comes in. He/she will look at what is already in place, and if it is adequate. It might be that the engineer says it won’t be any problem. Or...the decision might be that what’s in place is inadequate, and all new trusses must be installed. I hope this gives you a little more insight.

Thank you. I do understand the complexities of roofing and appreciate all of your advice. This is a 1976 mobile home. When our living room ceiling panels, vapor barrier and insulation were removed, the wood pieces fell apart like pick up sticks to the floor. Nothing was holding them together or up! The weight of my ceiling fan was pulling the structure down. Code didn't really exist back then. Now, MH are structured and held to a higher standard with stricter codes due to hurricanes, etc. I'm a handyman's daughter, a die hard DIYer with a lot of experience using power tools and I definitely don't mind getting blisters. I will seek an expert though per your advice. Thank you again for all the great information.