“There were tall old-fashioned casement windows punctuating every side, and these at least the four of them kept clean—each tenant was assigned one wall as his personal responsibility—because the light was too good to squander to dirt and was in fact the whole point of the space. There was a bathroom (unspeakable) and a kitchen (slightly less horrifying)”
A: I can guess "the light was too good to squander to dirt" means that the light too good that render the dirt more visual, make you see the dirt more clearly. Here it may related to metaphor, but it's a obstacle to related to the "squander" original meaning____to carelessly waste money, time, opportunities etc.
B:does it very common in artist that bathrooms are unspeakable, kitchens are less horrifying.