AT 390

Substrate type
Cement and cement lime plaster, concrete surfaces, cement finish, plasterboard, reinforcing layer in EPS-based insulation systems.

Substrate preparation
The substrate should be even, smooth, clean, stable, sound and properly cured (putty, cement finish and adhesives at least 3 days from application, plaster coatings after 28 days from application, cured concrete). Remove brittle and loose material of poor adhesion, patch chipped areas with ALPOL AZ 130 quick-setting mortar or ALPOL AZ 135 levelling mortar. Treat loose or absorbing substrates with ALPOL AG 700 deep-penetrating primer. Even out all surface irregularities using e.g. ALPOL AK 531 or ALPOL AK 532 insulation adhesive. On larger irregularities, use also ALPOL SW 145 fibreglass reinforcing mesh. Possible substrate unevenness may result in uneven aggregate distribution on the surface and, as a result, produce uneven colour. At least 12 hours before planned plaster application, thoroughly treat the substrate with ALPOL AG 705 primer stained to match the colour of the decorative plaster. Fine-grained patterns in dark colours on large continuous surfaces are not advisable. In all cases, in order to obtain the desired visual effect, it is recommended to divide the surface into smaller sections, e.g. imitating bricks, slabs or stone blocks, using painting tapes or ALPOL self-adhesive templates that are glued to the primed substrate. In order to achieve attractive deeper joints that imitate stone slabs, the substrate must be properly pre-treated using a rustic strip.

Instructions for use
Carefully mix the plaster with low-speed mixer before application. Apply continuously on a given surface to avoid differences in plaster texture. The surfaces should be joined using "wet on wet” technique. The breaks in application should be planned where colours intersect, where building bends, in rustication areas, under drainage pipes, etc. Only plaster from the same production batch should be applied on one continuous surface. If this is not possible, the colour consistency of the individual batches should be checked beforehand. If there are any visible differences, mix the plasters of individual batches with each other. Once the half of the container with the putty has been emptied, fill it with fresh putty from the second batch container and mix thoroughly. Once applied, the plaster has a milky-white colour that fades in the course of time. All plaster styles can be applied manually. ALPOL AT 390 plasters from SKIATOS colour chart can be applied by spraying. Due to its fine grain size, this plaster is recommended to be applied in two layers. One-layer application is possible only on a perfectly prepared, primed, level and smooth surface.
Manual application: Apply the plaster using a stainless steel trowel. Apply the first layer evenly to about 1.5 x grain thickness, then skim the surface, even out and smooth it before it begins to dry. Do not press the float too hard against the surface. Do not sprinkle with water or trowel the plaster surface. Apply the second layer after the first layer has fully set.
Spraying: ALPOL AT 390 plasters from SKIATOS colour chart can be applied using this method. If necessary, thin the plaster with small amount of water (2% – 3%, depending on the type of aggregate). Apply using a spraying gun with the so-called “funnel”, or a directly attached container that can hold ca. 3 – 5 kg of the product, held at a distance 40 – 50 cm from the surface. Select optimum nozzle air pressure for a specific plaster type (usually about 4 atm.). Recommended nozzle diameter 4 –6 mm. It is recommended to perform an application test in order to select optimum consistency of plaster, air pressure and nozzle diameter. Do not allow application of the material in excess, as it may cause streaks to appear. Apply the first layer of the plaster evenly on the surface with smooth horizontal movements. Spray the second layer in vertical movements with a “wet-to-wet” method, after the first one has initially cured (about 30 minutes). The product should be applied until the entire substrate is covered.

Tools
Low-speed mixer, basket mixer, stainless steel floats and trowels.

Working conditions
Before use, check if the colour and granulation are as ordered. Work in dry conditions, at the ambient and substrate temperatures between +8°C and +25°C as well as relative air humidity below 80%. Do not mix the plaster with other plasters, bonders or filling compounds. Do not thin with water. Avoid working in intense, direct sunlight, strong wind and high air humidity. Protect the plaster work from rain until it fully sets. High air humidity and low temperature can prolong setting time and change the colour shade. If exposed to moisture, “milky mist” may appear. It will disappear when the surface dries out. Therefore, avoid applying the plaster in areas where it will be exposed to contact with water or moisture (e.g. horizontal surfaces or those featured with insufficient inclination, small ponds etc.), and on components which are not properly insulated against moisture (foundations, fencing, or retaining walls).

Storage
In original, not damaged, tightly closed containers in temperature between +8°C and +25°C – shelf life 12 months from production date. Tightly close opened containers and use the remaining contents as soon as possible. Protect the product from freezing and overheating.

Notes
The specifications and instructions for use are based on the temperature of 20(±2)°C and relative air humidity 60(±5)%. Drying and final cure time may vary in different conditions. Contains: post-reaction mixture of 5-chloro-2-methyl-2H-isothiazol-3-one [EC no. 247-500-7] and 2-methyl-2H -isothiazol-3-one [EC no. 220-239-6] (3:1). May cause allergic reaction. Wear safety goggles. In the case of contact with eyes, rinse immediately with plenty of water and seek medical advice. Protect your skin by using protective clothing and gloves. Keep out of the reach of children. Clean fresh stains with water. The manufacturer assumes no liability for damage resulting from unskilful or improper use of the product. For patterns containing natural aggregates, the manufacturer does not guarantee full colour consistency among different batches of plaster.

General recommendations
Work according to building practice, observing health & safety standards as well as guidelines contained in the instructions to ALPOL thermal insulation system.

 * depending on the number of layers and total thickness of plaster

Declaration of conformity has been issued for the product.
Reference document: Outer plasters on organic binders PN-EN 15824:2010.
The product has been approved by the National Institute of Hygiene (PZH).
The Polish Classification of Goods and Services (PKWiU): 20.30.22.0.
Fidor, 2018-08-01. The present product sheet is valid and supersedes all previous issues.