If it makes you sweat, wears you out, and gets your heart rate going, it counts as exercise.
When I go on a cleaning spree, I feel the same muscles working as I do when I lift weights or do other forms of designated exercise. The fact that I have a scrub-brush in my hands instead of a weight doesn't mean my biceps and triceps aren't working.
Exactly
how you count your exercise, if you're keeping track of it, is a little tougher to gauge. I know Fitday has vigorous housework listed as an exercise option and lists calories burned from it, but I doubt it's entirely accurate; one person's "vigorous" may be another's "laid-back." Then again, I just use Fitday to record exercise as a means to ensure that I get some of it every day, not as an accurate log of calories burned.
Given the level of cleaning you're doing, I don't think it's at all unreasonable to consider your deep-clean days a workout. If anything, designated workouts mimic the natural exercise that people used to get naturally from going about their day--back when those days didn't include lots of labor-saving devices.