GENERAL-PURPOSE ADHESIVE FOR FOAMED POLYSTYRENE BOARDS AND MAKING REINFORCED LAYER IN EXTERNAL External Wall Insulation COMPOSITE SYSTEMS
FOR INTERNAL AND EXTERNAL USE

USE

AVAL KT 55 is a cement adhesive for fixing foamed polystyrene boards in external External Wall Insulation composite systems (ETICS). AVAL KT 55 can be used on typical mineral substrates such as concrete of all grades, aerated concrete, cement render, cement-lime render, sandstone, and rough surfaces made of bricks, blocks, hollow bricks and other similar ceramic or lime-sand materials. It is also suitable for surfaces covered with strongly adhering layers of façade paint or thin-layer render. It is suitable for internal and external use.

PROPERTIES

AVAL KT 55 is a ready-to-use dry mix of top-quality cement binder, aggregates and modifying agents. It is efficient, convenient and easy to use. The mortar is characterised by very good workability and easy forming as well as increased adhesion, elasticity and vapour permeability. It is frost-resistant and water-proof.

SUBSTRATE PREPARATION

Polystyrene panel fixing The substrate should be stable, even and structurally sound i.e. strong enough; it should be free from anything that may weaken adhesion, in particular dust, dirt, lime, oil, fat, wax, remains of emulsion and oil paint. Before work commencement, clean the substrate (water under pressure) and, if necessary, use AVAL KT 17 or AVAL KT 7 priming emulsions to reduce substrate’s excessive absorption. Prime also in case of such substrates as weak cement plasters, cement plasters and walls made of cellular concrete or slag concrete hollow bricks. Fill in larger irregularities and cavities with AVAL KM 41 levelling mortar or AVAL KT 111 plastering mix. In case of adhesion of foamed polystyrene boards on weak substrates of bearing capacity that can hardly be determined (e.g. dusty, difficult to clean), it is recommended to make an adhesion test. Reinforced layer preparation Before reinforced layer preparation, surface of foamed polystyrene boards should be even, clean, stable and de-dusted, if boards were ground after adhesion.

ADHESIVE PREPARATION

In order to prepare the adhesive, pour the whole content of the bag into a container with suitable amount of water (in proportion: 5.0÷5.5 l water for 25 kg of dry adhesive) and mix until homogenous. It is best to mix it mechanically, using a drill with a mixer. The adhesive is ready to use after 5 minutes and after remixing. It maintains its properties for ca. 4 hours.

APPLICATION

Board fixing Apply AVAL KT 55 adhesive on the inside of the board using the “strip-point” method. It consists of preparation of continuous circumferential block (at least 3 cm wide) at the edge of the board and even distribution of 6÷8 patches of 8÷12 cm in diameter on the whole surface. In total, apply so much to cover at least 40% of board surface (after striking down to the substrate, min. 60%) and ensure appropriate board and wall connection. Immediately after application of the mortar on the board, fix the board to the substrate by firm pressing and press down so that adhesive bed thickness under the board does not exceed 1 cm. In case of even and smooth substrates, the adhesive can be evenly distributed, using a notched trowel, on the whole board surface to ensure 2÷5 mm bed thickness. If additional External Wall Insulation fixing using fasteners is required, begin not earlier than 24 hours after board fixing. Reinforced layer preparation Begin preparation of the reinforced layer 3 days (on average) after adhering foamed polystyrene boards and after possible preparation of additional mechanical fastening. Distribute AVAL KT 55 on the surface of adhered insulation using a notched trowel and set a reinforcing mesh of glass fibre in the adhesive. Set vertical strips of the mesh and float so that it is not visible and does not directly contact foamed polystyrene boards. After the adhesive drying time (ca. 3 days), the finishing render can be applied. Avoid work in exposure to sunlight, rain and strong wind. The information comprises basic instructions of product application and does not relieve users of responsibility for work in accordance with good construction practice, method of External Wall Insulation work and OHS regulations.

CONSUMPTION

Foamed polystyrene board fixing - from 4.0 do 5.0 kg/m2 Reinforced layer preparation – from 3.0 to 3.5 kg/m2 The exact amount of adhesive used depends on the substrate (among others, evenness) and used board adhering method.

TOOLS

Drill with mixer, notched float made of steel, trowel. Wash the tools with clean water directly after use. Clean the remainder of the set adhesive that is difficult to remove with AVAL KL 55.

PACKAGING

Paper bags: 25 kg Pallet: 1050 kg in 25 kg bags

STORAGE & TRANSPORT

Store and transport in tightly closed bags, in dry conditions (pallets are particularly recommended). Keep dry. Shelf life in conditions complying with the requirements is 12 months from the date on the packaging.

CAUTION

Irritant. Contains cement. Protect skin, eyes and respiratory system. Keep out of the reach of children. Do not inhale dust. In case of contact with eyes, immediately irrigate them with plenty of water and seek medical advice. In case of ingestion, obtain medical attention as soon as possible and show doctor the packaging or label.

TECHNICAL DATA

Mixing proportions 0.20÷0.22 l of water for 1 kg of mortar 5.00÷5.50 l of water for 25 kg of mortar Pot life – 4 hours Open time – min. 25 minutes Adhesion: to concrete - min. 0.6 MPa to foamed polystyrene - min. 0.1 MPa Temperature: adhesive preparation temperature – from +5°C to +25°C Substrate and ambient temperature during work – from +5°C to +25°C Temperature resistance – from -20°C to +60°C Min. thickness of adhesive layer- 2 mm Max. thickness of adhesive layer- 5 mm Content of soluble chromium (VI) in ready-to-use mix - ≤0.0002 %. AVAL KT 55 is a part of AVAL- External Wall Insulation systems of external building walls