Wet basements may not be fully usable and might endanger the building foundation. We offer different methods to permanently waterproof basements: From the exterior with polymer-modified thick film sealants, mineral sealing slurries, or cold self-adhesive waterproofing membranes, which treat the entire external wall area and protect from water penetration. In repair cases, the waterproofing can be installed from the inside of the basement. This method is called “curtain injection”.

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External basement waterproofing with bitumen based waterproofing systems

1 Primer
KOSTER Polysil TG 500
2 Waterproofing pipe penetrations
KOSTER KB-Flex 200
3 Preparing wall/floor junctions
KOSTER NB 1 Grey
4 Installing fillets
KOSTER Repair Mortar Plus
6 Reinforcement
KOSTER Glass Fiber Mesh

The use of bituminous products is a standard solution for positive side waterproofing of basements. The systems are applied in a paste-like form and are seamless. They are easy and safe to use, and have crack-bridging properties. On clean, solid, stable, gypsum-free mineral substrates, KOSTER Polysil TG 500 is applied as a primer. This immobilizes salts present in the substrate and the solidifies the substrate. When preparing to waterproof on top of old bituminous coatings, KOSTER Bitumen Primer is used.

Pipe and cable penetrations are sealed with the permanently plastic putty KOSTER KB-Flex 200 and protected by a layer of KOSTER KB-Fix 5. These areas can be connected with a fillet of the thick film sealant or fitted with flanges.

To protect against water creeping behind the lower waterproofing connections, KOSTER NB 1 Grey mixed with KOSTER NB 1 Flex is applied first. To prevent stresses in the waterproofing, fillets are installed at wall / floor junctions.

The actual area waterproofing is achieved using KOSTER Deuxan 2C in two layers. KOSTER Deuxan Professional can be spray applied. KOSTER Glass Fiber Mesh is recommended in all thick film sealants and applications. This allows for a better control of the coating thickness and safely absorbs movement in the building.

Before backfilling the positive side, waterproofing is to be protected from mechanical damages and settling with KOSTER SD Protection and Drainage Sheet.

Always adhere to the specifications in the respective Technical Guidelines.

External basement waterproofing with cementitious waterproofing systems

1 Primer
KOSTER Polysil TG 500
2 Waterproofing pipe penetrations
KOSTER KB-Flex 200
3 Preparing wall/floor junctions
KOSTER NB 1 Grey
4 Installing fillets
KOSTER Repair Mortar Plus
5 Waterproofing layer
KOSTER NB 4000
KOSTER NB Elastic Grey
6 Reinforcement
KOSTER Glass Fiber Mesh

Cementitious sealing slurries are especially robust waterproofing systems with extremely good adhesion to mineral surfaces. They are not affected by moist surfaces, and become an integral part of the building structure on which they were applied. Cementitious sealing slurries are paste-like and are applied seamlessly to the building element being waterproofed. They are easy and safe to apply and can be installed as rigid or crack-bridging systems.

On clean, solid, stable, gypsum free mineral substrates, KOSTER Polysil TG 500 is applied as a primer. This immobilizes salts present in the substrate and solidifies the substrate.

Pipe penetrations are waterproofed using KOSTER KB-Flex 200 and sealed with KOSTER KB-Fix 5. Alternatively, these areas can be attached to the waterproofing using proper sleeves or flanges.

The actual area waterproofing is achieved using KOSTER NB Elastic Grey or KOSTER NB Elastic White in two layers. The installation of KOSTER Flex Fabric is recommended between the KOSTER NB Elastic layers to achieve an especially visco-plastic waterproofing layer. In areas especially in danger of water creeping behind the waterproofing such as wall-floor junctions, a substrate preparation with KOSTER NB 1 Grey mixed with KOSTER NB 1 Flex is applied. To avoid stresses in the elastic waterproofing, fillets of KOSTER Repair Mortar are installed in interior corners.

Before backfilling, the waterproofing is protected from mechanical damages and settling with KOSTER SD Protection and Drainage Sheet.

Always adhere to the specifications in the respective Technical Guidelines.

External basement waterproofing with cold self-adhesive waterproofing membranes

2 Preparing wall/floor junction
KOSTER NB 1 Grey
3 Installing fillets
KOSTER Repair Mortar Plus
4 Primer
KOSTER KBE Liquid Film
5 Waterproofing layer
KOSTER KSK SY 15
6 Waterproofing membrane ending
KOSTER KBE Liquid Film

Fast, clean, and easy: Exterior basement waterproofing with KOSTER KSK cold applied, self adhesive waterproofing membranes. No drying time, instantly watertight, with a tight control of consumption. Apply a primer coat of KOSTER KBE Liquid Film on clean, solid substrates. Pipe penetrations are sealed using flanges cut to size from KOSTER KSK Membranes. In areas especially in danger of water creeping behind the waterproofing such as wall-floor junctions, a substrate preparation with KOSTER NB 1 Grey mixed with KOSTER NB 1 Flex is applied. To avoid stresses in the elastic waterproofing, fillets of KOSTER Repair Mortar are installed in interior corners.

The actual area waterproofing is done with KOSTER KSK SY 15. The membranes are overlapped 4 inches. Corners and connections are made according to the directions on the packaging and according to the Technical Guidelines, and these areas are covered with KOSTER KBE Liquid Film. On vertical areas, the top edge is mechanically fastened and these fasteners are also coated with KOSTER KBE Liquid Film.

Before backfilling, the waterproofing is protected from mechanical damage and settling with KOSTER SD Protection and Drainage Sheet.

Always adhere to the specifications in the respective Technical Guidelines.

External basement waterproofing with thermoplastic waterproofing membranes

1 Waterproofing membrane
KÖSTER ECB 1.5 U S
KÖSTER ECB 2.0 U S

External basement waterproofing with thermoplastic waterproofing membranes

External basement waterproofing with curtain injection

When renovating, it is not always possible to expose the exterior walls through excavation. In this case you may first think of an interior (negative side) basement waterproofing, but in some cases, such as in historical buildings or buildings with special architectural requirements, this may not be desirable.

In these cases a curtain injection with KOSTER Injection Gel G4 is possible. The resin is injected through the wall from the inside to the outside. The resin reacts with water and binds it resulting in a waterproof, elastic solid. The injection is carried out with a special two-component pump, KOSTER Acrylic Gel Pump, and through patented KOSTER Distributor Lances. The injection material is dispersed on the exterior wall and in a short time reacts to a waterproofing layer. An alternative method is injecting KOSTER Injection Gel G4 into the building member itself. This so-called “area injection” is possible in porous or hollow building materials. In this case, the KOSTER Injection Gel G4 also reacts with any water present to form a waterproof, elastic solid.

Always adhere to the specifications in the respective Technical Guidelines.

Waterproofing under the foundation plate

1 Primer
KOSTER Polysil TG 500
2 Waterproofing layer
KÖSTER ECB 1.5 U S
KÖSTER ECB 2.0 U S
KOSTER KSK SY 15
KOSTER NB 4000
3 Embedded mesh
KOSTER Glass Fiber Mesh
4 Gliding Layer

5 Fillet
KOSTER WP Mortar
6 Protection of the waterproofing layer
KOSTER NB 1 Grey

A complete waterproofing system in new construction includes waterproofing the floor slab. Compared to the application on top of the concrete slab, the installation of the waterproofing layer underneath the foundation plate keeps the foundation dry and the concrete provides a better thermal insulation.

First, a primer such as KOSTER Polysil TG 500 is applied to the clean, sound, and solid substrate. KOSTER Polysil TG 500 is a standard primer that locks existing salts into the substrate, hardens the substrate, and provides a better bond between the waterproofing and the substrate.

The main area waterproofing made of KOSTER Deuxan 2C is applied in two layers with KOSTER Glass Fiber Mesh embedded in the fresh first layer. Embed the KOSTER Glass Fiber Mesh between layers as it provides an easy control of the layer thickness and absorbs the forces created by movement in the building.

Before pouring the foundation plate, plastic sheeting is installed in two layers to act as a gliding layer between the waterproofing material and the concrete. The waterproofing layer must be protected by a layer of unreinforced concrete. The vertical waterproofing is connected to the side waterproofing layer underneath the foundation plate. A fillet of KOSTER Deuxan 2C is to be installed in the connection area.

Always adhere to the specifications in the respective Technical Guidelines.

Waterproofing of pile heads

2 Waterproofing of pile heads
KOSTER NB 1 Grey
5 Waterproofing layer
KOSTER NB 4000
6 Embedded Mesh
KOSTER Glass Fiber Mesh

Damage in existing buildings is often caused by leaking pile foundations. Water can enter the building through the construction joints, or makes its way along the reinforcement steel. The waterproofing of pile heads must withstand heavy loads from the whole building, and needs be easily connected to the area waterproofing.

At first, all non load bearing materials and separating substances must be removed from the surface of the pile head. After that, the surface must be leveled and reprofiled with KOSTER Repair Mortar. This reprofiling must also include the installation of a fillet adjacent to the pile head. KOSTER NB 1 Grey is used to waterproof the pile head.

The waterproofing on top of the blinding layer is made with KOSTER Deuxan 2C. Embed KOSTER Glass Fiber Mesh into the fresh first layer. Before pouring the concrete for the floor slab, a gliding layer consisting of two layers of plastic sheeting is applied between the waterproofing and the concrete. Protect the waterproofing layer from mechanical damage when continuing with the application.

Always adhere to the specifications in the respective Technical Guidelines.

 

 

 

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