Waterproofing System for Old Roofs

Waterproofing terrace is a universal problem in Concrete Construction, mainly because the surfaces are flat. This means that the water cannot run off the structure quickly, and will move slowly or pool above the surface, creating opportunities for leakage, especially for old roofs. Decade-old buildings often show signs of leakage from ROOFS.  Terrace Roofing with Concrete Slope Screed or Insulation Tiles or Brickbat Coba Protection often have water leakage problems with deterioration of the top protection layer.

Reasons for Water seepage on ROOFS :

Once the materials in your roof age beyond their life expectancy, they begin to break down, compromising the integrity of your roof. Some of the reasons for water seepage are-

1. Cracks on ROOFS
2. Ineffective coving joints at Parapet wall – Slab junction
3. Improper sealing of gaps around Downtake Pipes
4. High Absorption of Stagnated water on poor quality Brickbat Coba System
5. Inadequate slopes on Protection Screed
6. Tiles joints not properly grouted with non-shrink mortar

Treatment Procedure for effective Waterproofing for roofs:

The application of a layer of impervious material which prevents water from penetrating. Making the structure waterproof or water-resistant so that it remains relatively unaffected by water or resisting the ingress of water. There are various treatment procedure for effective waterproofing such as-

1. Old Loose unsound protection screed to be removed and resurfaced with Polymer modified Mortar with good Acrylic Bonding Agent.
2. Different Cracks as per their nature have to be treated with proper crack filling compounds ( Shear filling the cracks superficially does not affect and cannot guarantee good waterproofing even though a good system is applied )
3. The parapet – wall slab junction to be checked for proper coving and to be redone if not properly treated earlier with slight saw cutting for I” depth and filling with polymer modified mortar and finished with polymer-modified mortar.
4. Gaps around down take pipes have to be re-grouted with Non-Shrink Mortar
5. Tile Joints with broken or loose joint mortar to be redone with fresh polymer-modified non-shrink grout
6. Above all the surface to be treated with Waterproof COATING SYSTEM shall be properly surface prepared with proper cleaning, and removal of loose debris etc.

Important DESIGN FEATURES of Waterproofing Systems

• Adhesion of the system
• Flexibility and resilience
• Weather resistance
• Water resistance
• Longer service life

Adhesion – GOOD Bond comes from Pore Filling

Polymer Modified Cementitious Systems

Is Adhesion happening?

• Polymer with cement viscosity is high to penetrate
• Polymer and powder when mixed ( starts gelling ) during the period of application AND bonding to substrate effects

Application Process –

Adhesion Bond Strength

La BrushSeal

Penetrating Waterproofing Repellent Primer for Concrete

Single Component Elastomeric Acrylic based, UV Resistant Waterproof Coating

Single component, acrylic based high flexible elastomeric waterproof coating which upon curing forms a tough, flexible and durable coating which is resistant to UV and other weathering agents like sunlight, frost, rainfall etc. Elastomeric waterproof coating is also used to protect exposed concrete structures against carbonation and chloride ion diffusion.

Characteristics and Salient technical features of the Coating

1. Excellent Crack Bridging mastic waterproofing system
2. Good Elongation property to withstand cyclic temperature
3. High Polymer Solid Content and Excellent tensile strength
4. Cured coating with Less Water absorption properties
5. Good All round Weather resistance product.
6. Moisture tolerant system
7. Excellent adhesion to Concrete
8. Self Curing  and quick Drying System

Salient Features of ACRYDEC SYSTEM:

1. Special Acrylic Co-Polymer Chemistry for good dimensional stability
2. Excellent Crack Bridging property >3.5mm
3. Elongation property of 400%
4. Well Cross- Linked polymer with less water absorption
5. Suitable for Application on Metal and Concrete
6. UV Stable

Author: J Srinivas Prasad,

Email: jsprasad@lagreensindia.com Mobile: 9900819917

For more details visit: www.lagreensindia.com