A wall panel system for forming a wall surface on wall framing studs, and having wall panels arranged with edges of adjacent panels located in spaces between two adjacent studs, a backing strip of wall panel material located in the space between two adjacent studs, behind the edges of the two adjacent panels, fastenings securing the edges of the two adjacent panels to the backing strip, a gap between the two panel edges, and an adhesive filler bonding compound filling the gap and bonding the panel edges to one another, and further bonding the panel edges to the backing strip. Also disclosed is a method of erecting a drywall consisting of attaching a backing strip to the back of a first panel, attaching that first panel to the studs, fastening another backing strip along a free edge of a second panel, erecting that second panel in edge abutting relation with the first and overlapping the backing strip on the first panel, and, fastening the second panel along the backing strip of the first panel and fastening the second panel to the studs.