Our old farmhouse had a makeshift addition put on sometime in the 1950's that appeared to be a sunporch eventually closed in. We removed the "old addition" and rebuilt to today's standards. Crawlspace gone, full basement, hello!
The original stone portion of the house was constructed in 1851 and has low ceilings - we wanted to make sure not to dwarf it with the high ceilings that we desired in the addition. We lived in the house throughout the renovation and had a makeshift kitchen in the sunporch... the washer/dryer were our countertops for 4 months! We got very good at grilling (everything) and now really appreciate our dishwasher.
We love the exposed stone wall in the dining area (former exterior wall), the salvaged beams on the island (pulled from the old addition). We are really happy to have been able to revitalize the house and love how the old and new parts of the house have blended.