All these joints to be treated with a mix of cement/sand mix with Koster SB Bonding emulsion and water at least 24 hours to application.

Fillets:
Similarly at all the junctions of the Retaining and the slab, the fillets must be built up with a mix of cement/sand/quartz sand mix with Koster SB Bonding emulsion and water at least 24 hours prior to the application.

Pipe Insertions:
Pipe inserts must be installed prior to the application of the Koster NB\Koster NB Elastic waterproofing system. At the opening in the slab around the pipe the substrate should be similarly opened up by cutting back around the pipes to give sufficient depth and cleaned thoroughly. This must be then built up with a mix of cement/sand mix with Koster SB Bonding emulsion and water at least 24 hours prior to application. .

Finally dampen all the surface areas thoroughly with clean water using high pressure water jet apparatus, as this is necessary prior to the application of the Koster NB system. The dampness in the substrate will ensure that the chemical reaction between the Koster NB system and the chemicals in the concrete substrate takes place completely. However the application of the Koster NB system should not be made over standing or running water.

MIXING AND APPLICATION :

Materials :
Koster NB cement based crystalline waterproofing system
Koster NB Elastic cement based crystalline waterproofing system
SB Bonding Emulsion liquid
KD 1, KD 2, KD 3
Water
Brushes

Mixing :
To one bag of Koster NB 1 - 25 kgs – add 7 - 8 liters of water premixed with 10 % Koster SB Bonding Emulsion. Mix thoroughly to a slurry consistency. The system is now ready for application.

The two components of the Koster NB Elastic system must be mixed together. Mix thoroughly to a slurry consistency. The system is now ready for application.

The KD system is a 3 component system, with each component being applied in sequence. KD 1 powder is a powder and mixed with water to a slurry consistency for application. The KD 2 powder and the KD 3 is used in pure form and in as is condition.

Application :
The application is done in 2 stages.
1. Application of the Koster NB system
2. Application fo the KD system over the actively leaking areas

1.
The Koster NB system is brush applied, on to the already damped surface. The brush on is done in 3 coats. . The coverage is 0.75 kg per sq. meter per coat and each coat is done perpendicular to each other. After the 1st coat there should be a gap of 12 – 24 hours before the 2nd coat is applied. Prior to the 2nd coat application the 1st coat surface should be dampened to ensure that the chemical reaction is complete on the underside. No water curing is required. Similar procedure must be followed for the 3rd coat. The finished surface should be left exposed for 48 hours for positive side treatment and 4 days for negative side after which further roof build up works can be carried out.

For treatment on the basement from the negative side, it is recommended that the treatment starts for the entire horizontal floor slab (width – 0.30 ms) onto the vertical wall surface and terminates on the ceiling (width – 0.30 m). For the positive side it is recommended that the treatment starts from the base of the raft and terminates at an extension of 150 mm on the basement ceiling slab. This will ensure that all the weak points are covered completely and the basement walls are completely watertight.

For all the pipe insertions, Masonry joints area the Koster NB Elastic system should be applied right around and onto the pipe section to make it completely watertight as 4th coat. The Koster NB elastic properties of the system will eliminate the possibilities of cracks developing at these junctions.

For the expansion joints care must be taken to complete the application of the Koster NB system right into in insides of the expansion joint first. Once this is complete and cured then a backing of thermocole is provided as a filler material and the final 25-mm must be filled with Polyurethene sealant. This will help to take care of the high expansion/contractions of the substrate at these points

All vertical and horizontal watas must be built up and then treated with the Koster NB and then the Koster NB elastic system as given above.

2.
After the Koster NB system has cured and dried the actively leading areas can be identified clearly. The actively leaking areas are first treated with the KD 1 slurry. This is a quick setting crystalline system which sets in 5 minutes approximately. This is followed immediately with the KD 2 powder. This is a very quick setting cement and sets in about 3 – 45 seconds. This is applied over the KD 1 and rubbed in by hand. This will immediately arrest the leakage. This is followed by the KD one treatment again. Within the 5 minutes the KD 3 is applied which is the sealer coat. This completes the applications and it will be seen that all the damp / wet areas will be dry.

Limitation:
The Koster NB system cannot be applied on running or standing water.
The Koster NB system must be protected from acid or sulphurous attack in concentrations exceeding that in Portland Cement Type I/II

SCREED :
The Koster NB system once installed must be protected by a protective screed from damage by other agencies working in the installed area. Screed of Cement sand mortar of 1:4 proportion for 20mm thickness . Further if applied on the positive side protection must be provided against mechanical damage during earth filling operations of same specification of screed.