Whether or not to use shelves for the washer and dryer or to stack the dryer directly on top of the washing machine is a topic that attracts thousands of comments on a number of forums.
Some people think that separate shelves are needed to ensure the safety of the two machines, limiting shaking or falling during use. But there are also opinions that it is possible to stack them directly to save costs and ensure aesthetics.

Experts say that depending on the model, weight, and manufacturer, you can decide whether or not to place the dryer directly on top of the washer. But in general, it is not necessary to use a separate shelf. In addition, many cheap models have a flimsy design that may not be safe.
Most of the current dryers are lightweight, when drying, the clothes are already wrung out, so there is little vibration when operating, so they can be stacked directly on top of the washing machine. Washing machines and dryers from some brands such as Coex, Electrolux, Samsung, LG, Panasonic have the same design and synchronized control panels.
In case you do not buy two machines of the same brand but want to stack the dryer directly on the washing machine, it is important to note that the four feet of the dryer must be in the upper surface of the washing machine. In addition, the washing machine must be firmly placed on a flat surface, not shaking, and both should have the same washing or drying capacity.
Heat pump dryers are often much heavier than conventional condenser or vented dryers, so they should have an extra attachment to secure them on top of the washer or should not be stacked on top of each other.