Base
Coarse, weather-resistant brick designed for thin-layer plastering is used as a base for thin-layer plastering. The recommended water absorption capacity of the brick is around 8-12%. If necessary, ask the plaster manufacturer for further instructions. A brick façade is laid using flush joints. Fescon M 100/600 masonry mortar is used as the masonry mortar. The mortar colour is chosen so that it matches the colour of the thin-layer plaster used. Depending on the conditions, allow the laid wall to dry for one to three days before plastering. This drying period ensures that the moisture inside the wall has time to even out. Before plastering, wet the wall so that it darkens but still retains its absorption capacity. Before starting work, apply a test coating to ensure the structure and tint. The tint is affected by, for example, the absorption characteristics of the base, the consistency of the mass, the coarseness of the surface, and the plastering method.
Mixing
Refer to the bag for how much water the plaster requires. Add the dry material to the water and mix with a concrete mixer for around ten minutes. With a power mixer or a drill paddle, around one to two minutes of mixing is sufficient. Let the plaster stand for around ten minutes and mix it again for a short while. Find the correct consistency at this stage by gradually adding the rest of the water. We do not recommend adding all of the water right at the start. In order to ensure uniform colour, the different batches should have the same consistency and mixing time. The finished plaster remains workable for around one to two hours.
Plastering
Begin work from the top part of the façade. The Fescon Thin-layer Compo Plaster is applied with a plaster sprayer. It can also be manually applied with a plastering trowel. After application, level the plaster with a steel trowel. Level the plaster so that it covers the entire plastering surface in a thin layer. The final finish is done by floating the slightly hardened plaster with a sponge or felt float.
You can obtain an even colour on the surface by wetting the float when necessary. The consistency of the plaster and the prevailing conditions affect the time when you should carry out the floating. The surest way to determine the correct time is to test floating. Due to this method being thin-layer plastering, the contours of the base are visible underneath the plaster. With thin plaster layers, the colour of the bricks may also shine through the plaster. We recommend choosing the thickness of the plaster layer by carrying out a plastering test. We recommend completing contiguous surfaces at the same time. You should "hide" the working seams in corners, expansion joints or, for instance, behind drainpipes. There may be some differences in the colour of different manufacturing batches, so we recommend ordering the required amount of plaster all at once. You should avoid plastering in strong, direct sunlight. Heavy rain soon after the plastering, internal moisture in the structure, thermal leakage and insufficient ventilation cause efflorescence. The risk can be reduced by covering the freshly plastered surface from rain.
After treatment
In very dry conditions, the plastered area must be protected with a plastic film or light spraying of water (the water must not flow) for at least one to three days. When the temperature is:
+20°C, protect the fresh plaster from rain and strong sunlight for one day
+10°C, protect the fresh plaster from rain for three days
+5°C, protect the fresh plaster from rain for seven days
Service instructions
A dirty surface treated with Thin-layer Compo Plaster can be cleaned with a pressure washer. Remove any damaged spots and repair the holes. No water should remain on the base after cleaning. Thin-layer Compo Plaster or Fescon Stone Colour KS paint can be used for recoating. The work instructions for the product used must be followed during coating and painting work. One treatment is normally sufficient for a cleaned, undamaged surface. Two or more treatments are needed for damaged areas from where the coating has been removed or holes have been patched.
Storage and handling of waste
See the separate storage and disposal instructions https://www.fescon.fi/en/material-bank