Procedure: Large Openings, Shafts, or Drop Ceilings
Expose the ceiling finish approximately 12" on all sides of the ceiling opening. Clean area to ensure adequate sealant adhesion.Install wood or gypsum board cover between joists. Screw it down to the top plate or adhere with sealant.Install spray foam over the edges of the cover to seal it to surrounding joists and ceiling gypsum board. Seal along the ends of the drop ceiling on either side of the ceiling joist with spray foam.Replace existing insulation and, if desired, install additional insulation.
