Encapsulation refers two-sided lamination as a moisture barrier. Full encapsulation provides additional protection by extending lamination 0f a poster or banner beyond the edge of the sheet. When media size supports it default encapsulation, when requested, is approximately 1/4 inch.
True full encapsulation requires trimming poster to exact dimensions before lamination so lamination may extend. In some cases, however, what is desired is for fully laminated poster with paper to extend beyond a printed border. When requesting encapsulation, specify your preference of full or flush cut; without specification, the latter is delivered.