When installing InSoFast panels in a ceiling application the goal is to provide as much contact between the studs and ceiling surface in order to maximize the holding power of the studs.
On the back of the panel, run a 3/8” bead of adhesive along dove-tailed ribbing of each stud. Add a bead of PL Premium 3x along the edge of the panel that will come in contact with the wall. The outer edge or where the first row of panels is placed.
One option is to install the wall panels before the ceiling panels just 2″ short of the top. This allows the ceiling panels to slip in between and sit on top of the wall panels around the perimeter add shims to firmly support the edge of the panel until the adhesive sets..
The running bond pattern in not always required on the ceiling but is it recommended for a flatter truer job. Brace the panels firmly until all adhesives has cured. A common, “T” brace is often used. Alternatively a concrete fastener can be used to support the panels and eliminate the bracing requirement.