Need some advice about where to start with this project.
I have a 100 year old story and a half home. I have to tear off the roof this summer and do a complete re sheet, as it has 4 layers of asphalt and a layer of wood shake under that, with no ridgevents or fans. This house does not breathe.

I was thinking of raising the trusses up and making the half a full second story, because I already have such a big undertaking with the roof anyways....

The stairs will need relocated because it is accessable from a bedroom now.
Also I think the fondation needs looked at to make sure it can support the weight of a full second story. But since it is a story in a half I wouldnt see why it wouldnt suppot a extra 4 feet up all the way around. Not to mention all the weight removed from 5 roofs...

So where do I start? Do I contact a architect, or a engineer?
Alo I am assuming that the structural support for this house is the chimney running from the basement to the above the roof in the middle of the house, what will need to be done to extend this?

Any help would be great. Thank you