What is house style in Sibelius?
A Sibelius house style is a collection of properties that gives a score a characteristic look. A new score is created from a Manuscript Paper built using a house style, which may be one that shipped with Sibelius or that that has been customized by a user to tweak some of the settings.
Where are Sibelius house styles stored?
It's stored in the C: \ Users \ username \ AppData \ Roaming \ Avid \ Sibelius \ House Styles folder, but there's nothing there.