Is a transitional edge between two faces of an object. Sometimes defined as a form of bevel, it is often created at a 45° angle between two adjoining right-angled faces. ( Wikipedia).
In waterproofing systems, making a chamfer is of great significance. Water normally gets stuck in areas which have sharp corners of 90° & on several occasions the leakage of water occurs from this the sharp angle of the water retaining bodies or areas where significant waterproofing is required. To minimize the effect of this, a chamfer is usually created to make sure that there are no sharp angles in the structure to minimize the effect of water coming in & out of the structure.