Absolutely cleaning your house is exercise. While you might not be in a gym pumping an iron or running on a treadmill, it's still exercise and requires you to do it to work and burn more energy than being sedentary. Cleaning the house is an example of moderate-intensity activity, the kind NASM and health experts recommend that you do daily to maximize health and fitness. Everyday tasks, such as cleaning the house, mowing the lawn, cleaning the car, buying food and other things, are examples of moderate exercise, which helps improve health and fitness.
Gardening and house cleaning jobs are an important exercise according to fitness studies. Your exhaustion after intense cleaning work is a sign that you are working hard. It may not be taken as a commitment to your daily physical exercise; however, it contributes to a healthy lifestyle. What a surprise we have here.
Do you burn more calories per minute doing household chores compared to lifting weights? Okay, it sounds a little scandalous, but the totally unscientific experiment seems to suggest it. The first place on the treadmill is something of a fact, while exercising on an exercise bike isn't that far off if you opt for circuit training. So is cleaning the house considered an exercise? Although the results are inconclusive, I think it can be considered a very light workout. I suspect that the perception that this is considered a workout comes from the amount of energy we exert during cleaning.
It also depends on how thorough you are and whether you actually get those nooks and crannies.