Plastic:
When attaching the plastic liners to the form, the first step is to identify the side to be poured against. The side facing the formwork has a smooth shiny surface; the concrete side has a slight “hair cell” appearance.
The most common method to attach the liner to the form is with screws or nails. Tek Drywall screws work well for this application and the nails or screws should be placed every 6″-12″on center around the perimeter and 18″-24″ in the center of the liner. Other options include pneumatic staples, which don’t hold as well so they should be applied closer together, and double sided tape. The recommended method for tilt-up application is wooden dowels inserted into the casting slab. “Formica top” adhesive is suggested for applying plastic liners to steel forms.
Urethane:
Urethane liners can be attached to the front or the back of the forms with bolts or lag screws. The head of the bolt can be screwed into the face of the liner and covered with a silicon or urethane caulking material. Or, for easy attachment, Spec Formliners can manufacturer your liners with T-Nuts according to your specifications where the head of the bolt can be screwed into the imbedded threads in the back of the liner.
For more information on the application process:
Plastic (PDF)
Urethane (PDF)