I really enjoyed this. I was captured by the reliable hook of an initially confounding fantastic or symbolic setting, gradually made comprehensible as information is revealed and the reader acclimatizes to the concepts in play. The infinite architectures of The House reminds me of the similarly spectacular House of Leaves, or the YouTube Backrooms phenomenon. It makes me want to revisit the symbolic locations of Banks "The Bridge". It reminds me of deeply evocative late nights, lost in endless videogame worlds.
About 2/3 of the way through, I caught a reference as a character is using childhood memories as part of a ritual to reopen a doorway to a lost world, from the rose garden of his childhood home. As potential doorways begin appearing, he notes "The color of the roses was supernaturally bright."
This is no doubt a deliberate reference to Aldus Huxley's "Doors of Perception" (bookwyrm.social/book/168195/s/the-doors-of-perception-and-heaven-and-hell-perennial-classics), a trip report on the opening of said doors during the psychedelic experience of mescaline, in which repeated reference is made to a supernaturally bright and vivid vase of flowers, "shining with their own inner light and all but quivering under the pressure of the significance with which they were charged".