Drill holes at 100mm centres along the mortar course of the walled to be damp-proofed using a 12mm drill-bit. Holes should be drilled to a depth slightly less than the thickness of the wall - see full instructions for suggested drilling depths for common wall thicknesses.
Unscrew the nozzle attachment from the Dryzone gun and insert the Dryzone cartridge.
Pierce the Dryzone cartridge using a sharp knife.
Replace the nozzle and screw tight. Insert the nozzle of the Dryzone gun into the full depth of the first pre-drilled hole. Squeeze the gun trigger and back-fill the hole to within one centimetre of the surface. When damp-proofing cavity walls, make certain that the holes in each leaf are filled.
Fill the rest of the holes with Dryzone damp-proofing cream in the same manner. When treating plastered walls, the plaster will have to be hacked off and replaced by a new plaster on a REPLA system.