Waterproofing by Membrane technology (Cement base)

 

Waterproofing!!!

First let us be clear, Why do you need waterproofing for your building especially over the terrace ?

Most of the user prefer to lay clay pressed tiles as a weathering course at the terrace. These clay pressed quality differs based on the quality& quality of raw materials used and the temperature at which these tiles were cured. These above parameters determine the cost of the product. Due to market competition and to sustain the market, the manufacturer produce the product which will last less than a decade. So during the monsoon season, through the cracks or damaged tile, the water seeps into the mother slab via shrinkage crack and damages the reinforcement. 

So to protect the RCC structure from the water seepage, we recommend to do waterproofing over the mother slab after 28 days of concreting.

Membrane based Waterproofing.

Though many types of membrane based waterproofing available in the market, we gonna share you our expertise on cement based water proofing in this post.

Cement based waterproof: 

As per the name, the waterproofing is done by mixing the cement and rubber latex and same is coated over the surface. Cement which is use here is specially manufactured for the waterproofing application. Cement is blended with hydrophilic content and once it mixed with latex the property changed to hydrophobic. Please don't try with the commercially available OPC/PPC cement with SBR latex. You may get the result but the performance guarantee may vary.

Cement based waterproofing  we usually suggest for the application on vertical surface and on the flooring of the toilet before screed. The cement based waterproofing can also be used on terrace subject to some conditions. The cement based waterproofing application is limited to some conditions like the water pressure on the membrane is negligible and doesn't fit for high foot traffic as the layer leaches out due to wear.

We usually procure the waterproofing chemicals from Dr.Fixit Pidifin 2K and Fosroc Brush bond. I have personally tried with other three makes that are available in local market, but the result from the Dr.fixit and Fosroc something which is beyond the performance guarantee of the manufactures.

In one of my construction site , I had applied two coats of Fosroc Brushbond over the mother slab and allow it for curing. Over the coating, a thin layer of cement mortar screeding is done with Fosroc WL as an additive to it. Due to COVID-19 restriction and man power shortage , the construction took more than 10 months to completed. Meanwhile the whole building was partially submerged in water and rest of the area were highly damped. I was surprised with the product that I did not notice any kind of dampness in the ground floor roof. From then I usually prefer Fosroc Brush bond to all my construction site.

Application of Cement based waterproofing, Here We Go!.

Step 1: Try to remove all the loose particle and clean the surface. Mild acid wash is suggested to remove any organic growth. Finally rinse the surface.

Generally in Fosroc Brushbond a 23kg pack you can find 23kg cement and 4 litres of rubber SBR latex and water . Mix the quantity as required . Usually with 23Kg pack we can cover 150 - 200 sq.ft two coats. 

Step 2: First coat the Joints/Corner with undiluted mixture and then add 2 - 4 litres of water and apply one coat of content in one direction say (North to South). Allow it dry for 4 - 6 hours before second coat. The Second coat shall be coated with lesser dilution and the direction of coating should be opposite of first coat i.e. (East to West). Make sure during the coating the surface should be moist and if possible plan the coating during late evening.

Step 3: Cure the coated area for atleast 2 - 3 days.

Now the surface is ready.

Remember this cement based membrane waterproofing surface is not fit for the foot traffic and hence Cement mortar flooring and plastering should be done.

Cost analysis :

Material Cost :  

 (i) 23Kg pack Fosroc cost around Rs. 2500+GST.

 (ii) 4inch brush - 3 nos

 (iii) Acid

 (iv) Air blower

 (v) wirebrush

 (vi) Fosroc WL plus as required

 (vii) PPC Cement

 (viii) sand 

Labour Cost : Rs.15 - 25/sq.ft. including 2 coat of waterproofing and Cement Mortar flooring/plastering

For clarifications and enquiry 

Please feel free to contact us.

Er . Aravind & Er. Ramarajan

Chrome Construction.

Mob No : 9094568211 / 9043788698

Email id: chromeconstruction@outlook.in

Suken RCC slab for wet area in Restroom

Application of Fosroc-Brushbond at Slab sunken area

First Floor level was treated with Fosroc Brushbond a Membrane based Waterproofing (Cement base)