In this paper, an algorithm for Boolean factoring is presented. The algorithm is based on a technique of rectangle covering. A distinctive feature of the algorithm is that no minimization step is required to achieve Boolean factoring. The method for computing Boolean products rests on the concepts of super-product, extended kernel and extended co-kernel-cube matrix. Results of a comparison with the algorithms GOOD_FACTOR and QUICK_FACTOR implemented in SIS are presented. SIS is a program for logic synthesis developed at the University of Berkeley. All performed tests indicate that the proposed algorithm realizes a good tradeoff between factoring quality and computing time.