Waterproofing Guidelines for Residential and Small Projects ( Sunken Area & Bathroom - New )

Published by Hemant Chauhan in Waterproofing.

Sunken Area & Bathroom - New - After Minimum 28 days of curing of the Slab

Surface Preparation

• Clear and thoroughly clean the surface with wire brush, electromechanical grinders and jute brush. 
• Ensure surface is totally dust-free by using a high speed air blower
• Wash the surface with water to identify cracks
• Mark the cracks with chalk to identify them properly

Repair of Crack

• Use a grinder to widen the identified crack by 8 to 10mm, clear the cavity by jute brush or blower.
• Repairs the cracks with mortar made with cement : sand as 1:4 and admixed with BS smartbond 100 at 5% of the cement weight. Before applying the repair mortar apply a bond coat of BS smartbond 100 neat by brush in the crack.

Application of Cove or Gola along the parapet wall and terrace floor

• Ensure wall plaster is complete and cured.
• Apply a bond coat of BS Smartbond 100 diluted with water 1:2 by brush just before making gola . cove  of 50mm 
• Make a mix of cement : sand  in ratio of 1: 4, add 5% BS Smartbond 100 by weight of cement in the mix and make a cove or gola along the wall on a still wet bond coat of BS Smartbond 100 applied before 
• Cure it for 3 days, by using jute cloth or water spray curing 3 times a day.

Application of Waterproofing Coating

• Always Ensure before starting, the surface is dust free, use a high speed blower if possible or jute brush to remove any dust.
• Type Cementitious 1 Part or 2 Parts

1. Priming: Apply a coat of 2k waterborne epoxy primer  BS SmartPrime WB EP, Resin 1 Part, Hardener 2 Parts and Water 3 Parts, and apply by brush on the entire repaired and prepared surface.
2. After a gap of 7 to 8 hours, 

• Applying the first coat of  Acrylic Cementitious System like MoistureZero Liquid chemical mixed with cement in 1:1.5 ratio
• After 4 hours, apply the second layer of MoistureZero mixed with cement in a ratio of 1:1.5 to finish the layer. 
• On Wall / Vertical surface the application should be minimum 300mm above the gola/cove line
• Cure for 3 days by jute sacks after 6 hours of final coat. After curing test waterproofing for 4 day by water ponding.

Apply Protection Plaster of 8 to 10mmthickness, prepared using cement and sand in ratio of 1:4 admixed with BS smartbond 100 at 1.5% be weight of cement and 6mm fiber to allow further built up of tiles etc to not damage the waterproofing.