The present No. 1A is an almost total reconstruction, in 1896–8, of the house which Cubitts had built on this site in 1862–4 for the historian and biographer, John Forster, who wrote his life of Dickens there. Forster had bought the freehold of the plot from Cubitts in June 1862 for £1,800. According to one journal he supplied his own designs, but the street elevation hardly differed from Cubitts’ other houses in this part of Palace Gate, although the house was, and still is, partially detached from its neighbours. Forster’s part in the design therefore was probably confined to the internal arrangements, which included accommodation for his famous library, and a fire-proof muniment room. Forster removed to Palace Gate from his house in Montague Square in 1864. After his death in 1876 his executors tried unsuccessfully to sell the house at auction and his widow continued to live there until 1894.

It was not occupied again until after the reconstruction of 1896–8. This was done for William Alfred Johnstone, the youngest son of the mid nineteenth-century newspaper proprietor, James Johnstone, from whom he had inherited a share in the Standard newspaper. For his architect Johnstone turned to a man in his early thirties (Johnstone himself was still only in his twenties) whose work was already well known to him. This was C. J. Harold Cooper, a prominent figure in the Arts and Crafts movement who died in 1909 with only a handful of buildings to his credit. His death was attributed to cirrhosis of the liver and exhaustion.The Johnstone family were Cooper’s most important clients. Two of William’s brothers (while both in their twenties) had already commissioned designs from him: a large Tudor-style country house at Newmarket for W. M. Johnstone in 1892 and a town house at No. 15 Stratton Street, Piccadilly, for H. A. Johnstone in 1895.  Cooper also designed the block of chambers at No. 16 Stratton Street for H. A. Johnstone. The external appearance of No. 1A Palace Gate is very similar to No. 15 Stratton Street, both houses being in a much simpler and less historicist style than the house at Newmarket. Perhaps with these London houses in mind the German critic Hermann Muthesius characterized Cooper’s style as imitative of historical forms but modern in its total effect.

Cooper was a member of the Art Workers’ Guild, and, in the words of his obituary, ‘a constant advocate of the closer co-operation and association of the architect and the craftsman’. To achieve this ‘he gathered around him a band of artists of distinction in their different crafts, who, working together under him and with him, were jointly responsible for the decoration of his buildings’.  The artists and craftsmen thus employed on the reconstruction of No. 1A, all of them members of the Guild, were Stirling Lee, W. S. Frith, F. W. Pomeroy and A. G. Walker (stone-, wood- and plasterwork); Nelson Dawson (ironwork); Selwyn Image and Christopher Whall (glasswork); John Cooke (frescoes and soft furnishings). Regular meetings were held in the house at which they criticized each other’s work. Considerable trouble was taken over the details, each feature being tried out in situ beforehand, and but for the ‘endless patience and care’ of the associate architect, Graham H. Nicholas, Cooper doubted if the work ‘could have been done at all’. Most of the artists and craftsmen also worked at Stratton Street, as did the contractors, James Simpson and Son of St. Marylebone and Kentish Town, a firm particularly favoured by Cooper. The work of the reconstruction was begun in August 1896.

In 1899 the finished house received an enthusiastic appreciation from G. H. Leonard in The Studio, the spokesman for avant-garde taste at the time: ‘from the great gable that holds itself so high down to the very doorstep that meets the street it has “distinction” written everywhere for those who know how to read.’ It was modern, up-to-date, and clearly of the nineteenth century (though not built in a nineteenth-century way); a ‘house of today’ without any affectations of being Tudor or Gothic, or in any particular style. It ‘leaves the impression’, said Leonard, ‘that it is a house built for a gentleman by gentlemen.’

Johnstone lived in the house only very briefly between 1898 and 1903, when he removed to Wadham Gardens, near Swiss Cottage. During his occupation of No. 1A he appears to have shared the house with Alfred E. T. Watson, the musical and dramatic critic of the Standard and The Times.

With its tall gable and Portland stone façade, considered ‘rather audaciously white’when new, the exterior of No. 1A contrasts sharply with the staid brick and stucco-work of its neighbours.The exterior is unmistakably of its own time, as Leonard said, while recalling the wealthy burghers’ houses in North German and Flemish cities. The carefully contrived vertical emphasis of the design is skilfully set off by the slim pilaster strips which frame the building, whilst the finely jointed ashlar of the facade is saved from monotony by the variety and disposition of the mullioned-and-transomed windows with leaded lights