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.
Pwllheli
Pwllheli is a community and the major market community of the Llyn Peninsula (Welsh: Penrhyn Llyn) in Gwynedd, north-western Wales. It had a population of 4,076 in 2011 of whom a big proportion, 81%, are Welsh speaking. Pwllheli is the area where Plaid Cymru was founded. It is the birthplace of the Welsh poet Sir Albert Evans-Jones (bardic name Cynan). Pwllheli has a variety of shops and other services. As a neighborhood railhead with a market every Wednesday, the community is a gathering point for the population of the whole peninsula. For many years a vacation camp run by Butlins ran a couple of miles from Pwllheli at Pen-y-chain. During the Second World War it ended up being a naval camp, HMS Glendower, and it operated a hospital for wounded servicemen at Brynberyl on the Pwllheli to Caernarfon road two miles out of community. After the war, Butlins re-established the holiday camp. The camp, now renamed Hafan y Môr ("Haven of the Sea"), has actually been redeveloped as well as is currently run by the Haven group.