 Ayrton was in practice on his own from 1899, and in 1903 was at 14, Belsize Park Gardens, London.One of his early buildings was a house called Hall Ingle, at Heath End, Checkendon (1902), "...by Mr. O. Maxwell Ayrton, for, and decorated by, Arthur Hacker, Esq., ARA".Hacker painted Ayrton's wife and exhibited the portrait at the Royal Academy in 1902.