Not all of the Houses necessarily have “house colours” as such. There are some traditions within the houses, some of which you’ve already identified:
The Tremere tend to wear dark robes for formal occasions whose exact shade varies between blue black (for the youngest magi) to pure black to charcoal grey
Redcaps have their redcaps
Tytalus tend to wear an item of clothing that is either purple or green, depending on their political affiliation. Spiral iconography is also common
The Jerbiton have deliberately spread the idea that a “wizard” wears robes embroidered with mystical symbols, often blue, and conical hats with brims. They may therefore dress as such whilst being obviously wizardly to mundanes.
There are certain sub-traditions within Ex-Misc that may have their own dress (for example, the Columbae often wear white or very pale clothing) but nothing universal to the House
I don’t think the Bonisagus or Guernicus have any particular traditions that I’m aware of, and similarly I don’t remember the Mercere having white / red robes.
Members of various societies and mystery cults may also have particular symbols they wear.