How does Garth Nix use imagery in Sir Thursday?

The conclusion of Part II, which occurs after Paul's hostile, paranoid confrontation with his parents, shifts his apprehension abruptly to the room and to the activities in the house. The imagery is impersonal, Hopkinsesque in its disjoint, acute precision:

He could hear the soft irregular flutter of the flames; the cluck-click-cluck-click of the clock; far and faint, two sudden spurts of laughter from the kitchen, as quickly cut off as begun, a murmur of water in the pipes; . . .