N.E.S.C.A House was designed, by Emil Sodersten, on contemporary English lines in keeping with the work of Wells Coates and George Coles. Described as having a "heavy, streamlined form", the "new style was the streamlined functionalism of leading European architects". Structural drawings show the main buildings framework to be of concrete encased structural steel with mild steel reinforcing rods used throughout the structure. Concrete floors and some secondary floor beams appear to have been cast in-situ and were specified to use normal Portland cement, sand and course aggregate. It was reported to be in good condition as at 20 May 2009, although some of the significant fabric is in need of repair or maintenance. Some of the original fabric has also been removed or relocated. NESCA House is of state significance as an outstanding Art Deco building by the architect Emil Sodersten. The House is evidence of Newcastle's shift from a coal port to a heavy industry city. It is also intimately linked to perceptions of electricity in the 1930s as a novel energy source that was the way of the future. The Art Deco style, rather than a more traditional building, is a reflection of these perceptions. Nesca House was listed on the New South Wales State Heritage Register on 2 April 1999 having satisfied the following criteria. The place is important in demonstrating the course, or pattern, of cultural or natural history in New South Wales. NESCA House is of State significance as evidence of the development of Newcastle from a coal port into a heavy industry city and the subsequent increase in importance to the State's economy. The House is of State significance as evidence of the historical integration of electricity into society and the notion of "progress through electricity". The House is of State significance as evidence of the practice of local government activities and the shift through local and regional to state electricity supply. The place has a strong or special association with a person, or group of persons, of importance of cultural or natural history of New South Wales's history. NESCA House is of State significance as the work of Emil Sodersten, an eminent architect of the 20th century. The place is important in demonstrating aesthetic characteristics and/or a high degree of creative or technical achievement in New South Wales. NESCA House is of State significance as an outstanding example of Art Deco style with tendency towards Functional Modernism. It expresses the change from traditional design towards the concepts of modern efficiency, timesaving and functional designs.