Waterproofing treatment of rcc water tanks/ lift pits


  • Placing 12mm N.B.M.S. threaded Nozzles of 75mm length by drilling or making holes with suitable tools upto required depth in an approximate grid pattern at a spacing not exceeding 1.5 M c/c on all horizontal and vertical internal surfaces of water tanks including construction joints & critical points, if any and fixing them with CICO No. 3 (quick setting compound) admixed with cement.
  • Injection of ready to use non-shrink polymeric rheo-plastic grout CICO Grout E1 admixed with water through the Nozzles by grouting pump under pressure not exceeding 2.5 kg/ cm². The grout should flow through all pores and voids thereby sealing them.
  • Removing the projected parts of nozzles if any, & making the surface smooth with Tapecrete/Polymer modified cementitious (PMC) mortar (Tapecrete P-151: Cement: Silica Sand = 1: 2: 4-6 by weight) mortar.
  • Cleaning the concerned internal RCC surface by means of wire brush to expose the concrete surface which should be free from all loose particles, dust, laitance, etc.
  • Making 25 x 25mm size concave corner fillets with Polymer modified cementitious (PMC) mortar (Tapecrete P-151: Cement: Silica Sand = 1: 2: 4-6 by weight) at all joints of horizontal and vertical surface. Also the joints of outlet pipes and concrete/masonry are to be sealed with PMC mortar. In case of PVC pipes, the joints should be sealed with epoxy putty, CICO Poxy LC or epoxy mortar CICO Poxy 2125.
  • Application of first coat of Tapecrete P-151– Acrylic Polymer Modified Cementitious slurry (Tapecrete P-151: Cement = 1: 2 by weight) coating over the internal RCC horizontal & vertical surfaces.
  • At the green stage of Tapecrete, laying 30-40 gsm Fibre Glass Cloth. Then this coat is allowed to get dry for 4-6 hours.
  • Application of second coat of Tapecrete P-151 slurry coating. This coat is allowed to dry for 4-6 hours.
  • Application of one final coat of Tapecrete brush topping (Tapecrete P-151: Cement: Silica Sand = 1: 2: 2 by weight) over the concerned surface.
  • Moist curing of Tapecrete system for next two days.
  • Laying 15-20 mm plaster in the ratio 1: 4 (Cement: Sand) admixed with CICO Super ontreated surface.
  • Water curing of plaster as per good engineering practices.