Were staircases built around the same time but in non-strategic/non-fortified buildings (private manors etc.) notably different? Or were spiral staircases only

Were staircases built around the same time but in non-strategic/non-fortified buildings (private manors etc.) notably different? Or were spiral staircases only built in circular towers that existed primarily for defence? Presumably the narrowness was largely due to the difficulty of being a strong enough tower with a wider radius.