It shouldn’t do. Most companies will do all the interior work first, and the last job to do will be creating the opening from the house to the conversion. A reputable company will make sure they cause as little disruption as possible during this time.
Tywyn
Tywyn, formerly spelled Towyn, is a town, neighborhood, and also seaside resort on the Cardigan Bay shore of southerly Gwynedd, Wales. It was formerly in the historic county of Merionethshire. It is popular as the location of the Cadfan Stone, a stone cross with the earliest known instance of created Welsh, as well as the home of the Talyllyn Railway. At the time of the 2001 census, 40.5% of the population were recorded as Welsh speakers. By the 2011 census this had actually decreased to 37.5%. These fairly high numbers (offered the town's demography) show the use of both Welsh as well as English as the tool of instruction in Ysgol Penybryn, the community's primary school. An Estyn examination record in 2010 noted that concerning 11% of the kids at the college came from homes where Welsh was the main language.