Disadvantages with the Boundary Representation
(i) It requires more storage than the corresponding half-space method.
(ii) There is no guarantee that the object created is valid (i.e. complete, unambiguous, uniquely defined). Additional checks for validity, such as Euler's Rule, will be needed to ensure this.
(iii) It is usually less robust than the half-space method.
(iv) Each object is defined independently, without reference to other objects in the system. It is not easy to define "generic" or "parametric" models for families of parts.
(v) Its main disadvantage is that it requires large amount of storage. It is also a verbose scheme. In addition, faceted b-rep is not suitable for many applications such as tool path generation.