Dates noted in Victor Horta’s diaries

 1898 14 August : application for planning permission submitted to the Commune of Saint-Gilles (granted 28 September)
December: plans

 1899January: balcony
February: balcony, white stone and canopy ordered
April: first floor drawings 
May: dining room plans and cross-sections
June: stonework details
July: staircase
August: plumbing, gas and central heating plans
September: marble staircase
October: blue stone for pavement ordered
December: dining room re-grouting

 1900 February: grilles drawings
May: dining room windows drawings; shutters ordered
June: bells templates

 1901 March: office set up; sculpture studio fully functioning

 1902 dining room doors

 Dates of alterations

 1906 House extended in the direction of the garden: salon,first floor, second floor (balcony and winter garden). Planning permission sought 15 May; granted 19 October

 1907 Studio cellar enlarged with a view to improving the light and ventilation
Planning permission sought 24 December; granted 14 January 1908

 1908 Studio enlarged
Planning permission sought 14 January

 1911 Alteration of part of the ground floor from studio to garage

 1915-19 Horta in England and the United States

 1919 Horta sells the two houses and settles in avenue Louise

 1961 House purchased by the Commune de Saint-Gilles

 1963 House and studio ‘listed’ by Royal Decree

 1969 Museum opened to the public

 1973 Studio purchased by the Commune of Saint-Gilles; the two buildings are connected again