Waterproofing balconies and terraces

This field poses the highest demands on waterproofing. It must be able to resist the weather, be waterproof and provide a certain structural stability. Also, outside the movements of the construction members are usually comparably large so that it is necessary to use waterproofing systems with high crack bridging capabilities.

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Waterproofing of balconies and terraces with liquid applied bitumen based waterproofing systems

Balconies and terraces are constantly exposed to rain,splash water and high temperature fluctuations. Therefore the waterproofing should always be crack bridging.

When working with liquid applied bituminous waterproofing the prepared and clean substrate is primed with KÖSTER Polysil TG 500. A rounded fillet made from KÖSTER Repair Mortar Plus is installed in wallfloor-junctions in order to protect the subsequent layers from damage caused by movement.

The waterproofing is carried out with a liquid applied coating in two layers. Ideally suitable is KÖSTER KBE Liquid Film. Alternatively the rubberized bitumen thick film sealant KÖSTER Deuxan 2C (4 – 6 mm) can be applied. In the wall-floor-junction and areas in danger of cracking KÖSTER Glass Fiber Mesh is embedded into the fresh first waterproofing layer.

A screed protects the waterproofing against mechanical damage. A gliding layer consisting of 2 layers of PE-foil is installed under the screed.

Always adhere to the specifications in the respective Technical Guidelines.

1 Primer

KÖSTER Polysil® TG 500

2 Installing fillets

KÖSTER Repair Mortar Plus

3 Waterproofing layer

KÖSTER Deuxan® 2C
KÖSTER Glass Fiber Mesh
KÖSTER KBE Liquid Film

Waterproofing of balconies and terraces with cold applied self adhesive membranes

A fast and easy method for waterproofing balconies and terraces is using the cold applied self adhesive KÖSTER KSK waterproofing membranes.

The solid and clean concrete substrate is primed with KÖSTER KBE Liquid Film which provides an excellent bond between the concrete and waterproofing layer. In case of temperatures below 0 °C the non water based KÖSTER KSK Primer SP is used.

A fillet in the wall-floor-junction can be easily installed by using the KÖSTER KSK Triangular Ribbon: Remove the protective foil, press into the primed corner, done! Alternatively, before priming the substrate a fillet made of KÖSTER Repair Mortar Plus is applied.

The standard area waterproofing is done with KÖSTER KSK SY 15. In case of temperatures below 0 °C KÖSTER KSK AW 15 is the material of choice. The waterproofing membranes are simply bonded onto the prepared substrate and overlapped min. 10 cm on each side.

If the waterproofing is applied vertically onto a wall, the waterproofing membrane is mechanically fixed. Connections and overlaps are sealed with KÖSTER BS 1 Bitumen Paste. If the top end of the waterproofing is to be plastered, it can be covered with KÖSTER Butyl Fix-Tape Fleece.

A screed protects the waterproofing against mechanical damage. A gliding layer consisting of 2 layers of PE-foil is installed under the screed.

Always adhere to the specifications in the respective Technical Guidelines.

1 Primer

KÖSTER KSK Primer BL
KÖSTER KSK Primer SP

2 Fillet

KÖSTER KSK Triangular Ribbon
KÖSTER Repair Mortar Plus

3 Waterproofing layer

KÖSTER KSK AW 15
KÖSTER KSK SY 15

Waterproofing of balconies and terraces with mineral based waterproofing systems

The mineral waterproofing of balconies and terraces is carried out with crack bridging KÖSTER NB Elastic (white or grey). This waterproofing is resistant to foot traffic and can be covered with tiles. It also bonds to damp substrates.

Before installing the waterproofing the substrate is hardened and prepared with the primer KÖSTER Polysil TG 500. Fillets are installed with KÖSTER Repair Mortar Plus. In the wall floor junction and all areas in danger of cracking KÖSTER Glass Fiber Mesh is embedded into the fresh first waterproofing layer.

Concrete repair work is done with KÖSTER Betomor Multi A. The concrete surface must be mechanically cleaned and a solid substrate achieved. Reinforcement steel has to be thoroughly cleaned from rust by sandblasting. In case of severe damage the reinforcement has to be strengthened.

Minor damages in the concrete surface can be levelled with KÖSTER C-Coat, and painting done with KÖSTER Silicone Paint White.

Always adhere to the specifications in the respective Technical Guidelines.

1 Concrete repair

KÖSTER Betomor® Multi A

2 Concrete protection

KÖSTER C-Coat
KÖSTER Silicone Paint White

3 Primer

KÖSTER Polysil® TG 500

4 Installing fillets

KÖSTER Repair Mortar Plus

5 Waterproofing wall / floor junctions

KÖSTER Flex Fabric

6 Waterproofing layer

KÖSTER NB Elastic 1C White
KÖSTER NB Elastic Grey
KÖSTER NB Elastic White