liner pins and adhesive: treat them as one attachment system insulation, liner, vapor barrier & condensation duct liner pins adhesive weld pins washers spacing install the approved adhesive coverage and mechanical fasteners together, with edges, corners, seams, and airflow-facing surfaces secured as specified. loose liner can delaminate, restrict airflow, contaminate the system, and become impossible to repair after installation. approved liner submittal, manufacturer installation instructions, project specification what adhesive coverage and pin pattern does this liner system require for this duct size and velocity?