Unless you bring a lot of dirt or sand, live in a dusty area, or have pets, you only need to vacuum hard surface floors once a week. However, dust, dandruff, and other allergens can penetrate the cracks between the floorboards, so you don't want to let it sit any longer, unless it's a room you use infrequently. However, if you live in a home that has mostly carpets, you should plan to vacuum at least twice a week. Rugs can hide more dust than bare floors.
Crumbs can also accumulate in carpet fibers and, when broken down, can cause bad odors and bacteria to accumulate. Vacuuming with the right frequency is one of the best cleaning tips you can learn for your home, says Scott Johnston, cleaning expert at Carpet Care of the Carolinas.