Waterproofing preparatory works – Core Cut packing

 Core Cut packing is one of the preparatory works for waterproofing.

This is to be ensured in Plumbing penetrations. For example, Core Cut packing will be done for plumbing lines that are crossing the RCC members in toilets.

Core Cut packing is the process of fixing Plumbing pipes in RCC members (Slabs or beams or RCC walls) in their cutouts / core cuts.

Procedure for Core Cut  packing in toilets:

1)Core cutting location to be marked in the floor considering the tile layout. Then the core cutting is done with diameter slightly higher than the plumbing pipe (ex: for 110mm pipe core cutting should be 130mm to 150mm).

2) Side face of the core cutting area and plumbing pipe should be roughened for better bonding. Also a Bonding agent has to be applied Like Latex 45 :-

Ratio 1:1

1 litter latex 45 + 1 to 1.5 kg Cement mix with Properly.

Application over the pipe 2 inches over Above and Bottom near to Slab joint Top & Bottom.

Setting time-24 Hours (in Winter)

12 Hours (In Summer)

2)From the bottom Closing to be done for holding the Core Cut packing material. (Please avoid using backer rods, gunny bags or ropes).

And With the help of plumber the plumbing pipe should be positioned properly by checking the location and verticality.

Finally by  the non-shrink grout material has to be used for filling the gaps. In every steps manufacturer’s specifications has to be followed strictly.

NS 50 Grout (In powder Form)

1 kg mix with 180-200 ml water

And Pipe Grout Properly.

setting time-2-3 Hours.

3)After 3 Hours application of Sanigaurd Primer Coat- Liquid (Area Should be Dry and Dust Free) 2 inches periphery over Core cut.

Setting time 3 Hours.

4)After 3 hours - Single coat of Sanigaurd.

5)Joint Tape- just after application of Sanigaurd do not let it dry, Should air Tight and Completely Collared to the Pipe.

Setting of it 4 Hours.

6)After 4 Hours Second coat Sanigaurd

Setting time- 4 Hours.

7)Ponding test / Flood test should be carried out for 48 hours to check proper packing.

The above explained procedure can be followed for all horizontal slab Core Cut packing.

that is,

• Floor trap outlets, Floor mounted EWC points in toilets.
• Floor trap outlets in Balcony, Utilities & Podium slabs.

For vertical RCC members like Beams & Walls, there is a another procedure to be followed.

This will be posted soon…