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# What documentation is used to determine whether or not a building constitutes a dwelling?

The decision is taken by the tax office, based on the taxpayer's detailed explanations of the condition of the building. 

The tax office may ask the taxpayer to support his explanations with invoices for work carried out, receipts for building materials, architects' or engineers' plans, applications for planning permission, or any other means of demonstrating that the building has undergone or will undergo work essential to its occupation.