Basically if they feel the condition of the living environment is having a negative or detrimental effect on the children.
Some of it can show other things too. Inability to cook, prepare, serve, freeze food.
Inability to manage keeping on top of laundry/dish washing.
Inability to provide secure clean safe beds for the children.
Examples of a chaotic lifestyle. They love the word chaotic.
Lack of routine or stability.
Living in filth.
Living in filth which is a human health hazard.
No food in fridge/cupboards if children are hungry. No regular mealtimes. Nothing healthy being eaten.
Empty cans/bottles of wine/spirits/beer/cider.
Walls needing a lick of paint. Stained carpet. A stink.
Shit, piss, vomit everywhere.
Disarray more or less.