Two weeks ago I shared some of the rules on how servants were to behave in the Edwardian days around their masters. So I figured this week, I’d share the other side–how masters and mistresses are to act with their domestics.
Children of the family are the only members of the household given free rein both above and below stairs–adult members of the family ought to provide notice to the servants before inspecting the kitchens or other servant areas.
For the most part, the family deals primarily with the upper servants–the butler, the housekeeper, the cook or chef, the lady’s maid and valet. A trusting and professional relationship is to be cultivated and maintained. The butler is always to be addressed as “Surname” (the Mr. is optional), the housekeeper is always “Mrs. Surname” whether married or not. The lady’s maid is usually “Miss Surname,” though if a mistress is especially fond of her, she may occasionally use her given name. The valet is always “Mr. Surname” as well. (Sometimes the title is dropped for these upper servants, and they will be called only by their last name, but never by their first.) If a house employs a cook, they are “Mrs. Surname” but if a chef de cuisine, then one would call him “chef” or “Monsieur Surname.” 
All other servants are addressed by their given name when one is giving them orders but are otherwise not to be addressed at all. The family ought to limit their dealings to the upper servants whenever possible.
Footmen are a sign of a family’s prestige, something only the very wealthy can afford–and if they have more than one, then oh la la! They must be somebody! But they are lower servants and do not expect to be addressed other than to receive orders.
Other than cleaning, the primary task of the housemaid is to be invisible. For the most part, they will clean a room when no member of the family is expected to be in it. But when they must clean the foyer or entryway or Great Hall, masters are to do them the courtesy of ignoring them–this spares them the embarrassment of having to explain their presence. 
If a family employs a tutor for the children, he is to be addressed as “Mr. Surname,” likewise a governess would be “Miss Surname.” These individuals may be invited to join the family on occasion at meals, but they do not expect it.
Apparently (and I found this shocking!) it was a tradition for lower servants to be given new names upon joining a household. In part because the lower staff was in an almost constant state of flux as they sought better positions elsewhere, and masters couldn’t keep up with them all, LOL.