What an EWS1 is, and who it is for
It is an industry form for recording an assessment of a building's external wall system, developed with the Royal Institution of Chartered Surveyors, UK Finance and the Building Societies Association. It is not a safety certificate and it is not a statutory document.
Its audience is valuers and lenders. It exists so that a valuer can value a flat in a multi-storey building without having to form a view about the external walls themselves.