Abstract: A fiber wallboard, or similar rigid or non-rigid substrate, is directed via a conveyor through a roll coater for providing an adhesive layer on one side of the substrate. Packages of continuous strands, such as textile yarns, are supported on a yarn creel, and drawn through expansion combs and underneath a nip roll for being press rolled into the adhesive coating layer. The pattern of lateral yarn separation established with the expansion combs creates a particular design on the finished face of the substrate, and may be varied. The substrate with applied strands is dried and trimmed. Marginal edge yarns are particularly located relative the substrate edges so that yarn gaps surround seams between adjacent panel substrates. Seaming tape with additional textile yarns supported thereon may be fitted in the gaps to hide such seams.