A tankless toilet is usually used in businesses because bathrooms in business are for practical use, rather than for relaxation. Regardless of whether you are placing your tankless toilet in your home or your business, the following measurements needs to be taken. Measure from the wall to the closest toilet bolt. If this distance is the same or larger than the distance will be on your new tankless toilet, then it will fit in your bathroom. In compact bathrooms, it is wise to measure the width of the toilet in order to ensure that the new toilet is not too wide.