Loki only wears a t-shirt or sweatshirt in the house if it's exceptionally cold in here and he and I are shivering. Otherwise it's like 72 in here
Plus he is usually snuggling in one of my 5 fleece blankets. Some days even if it's really cold he will only tolerate a t-shirt or light sweatshirt. I put his COAT on him if it snows or if I take him in the car early in the morning and don't warm it up first. Then he's in his coat and wrapped in a blanket.
He lets me know if he is hot or not comfortable and wants his shirt off. He will rub up against the couch or do his "ugh there is something on me" dance where he rolls all over the floor.