Nora Batty is always cleaning up, both inside an outside the house. Yet in this episode, she comes outside with a rug and shakes a lot of dirt out of it. But this is done for the laugh, since she's shaking it all over Wally, who's hiding just below the railing.
When Ivy brings Sid into the kitchen, she slams the door shut and the whole wall moves, indicating it's a movable part of the set.
In the café, when Compo is going on about Nora Batty's wrinkled stockings, we see a stage light reflected in the light switch next to the door.