Remove any loose and flaking coatings and paints from the concrete surfaces with the aid of water sand blasting, for example. Depending on the type and extent of the damage, remove the damaged concrete by chiselling, water sand blasting or milling. Shape any cavities and clean any rusted reinforcement bars to grade St 2 or replace them with new ones. Apply Fescon Adhesive Plaster on the rebars and fill the cavities with Fescon Repairing Plaster. If necessary, level the repaired surfaces with Fescon Overlevelling Plaster. Roughen the new concrete surfaces and clean them of cement paste with the aid of water and sand washing or steel brushing, for example. The surface can also be treated in connection with element manufacture. New concrete surfaces can be painted after one heating season at the earliest.
Remove any existing loose and flaking coatings and paints from the plaster surfaces. Remove any plaster layers that have become separated from their base until you reach an undamaged layer of plaster. Apply the repair plaster using a method suitable for the depth and extent of the damage. Shape the structure of the surface plastering to match the original plaster surface. Take account of the composition of the old plaster. Let new plaster surfaces and areas where a thick layer of plaster has been applied dry for a sufficient period of time before painting. The guideline is 2 days/mm of plaster, depending on the conditions. When pre-treating and painting bases containing asbestos, take the necessary protective measures specified in official regulations
Before beginning the work, carry out a test painting to ensure the correct tone.
In priming, a maximum of 5% of the paint can be thinned with water. Please note that the paint mixture must be used within 24 hours of mixing. If the base is highly absorbent, it may be necessary to pre-treat it with Fescon Silicone Resin Primer MC.
Top coat application
Apply the top coat using undiluted Fescosan façade paint. The base must be dry and clean. During coating and drying, the air temperature must be at least +5°C and relative humidity below 80%. Apply the paint with a brush, roller or airless sprayer (nozzle size 0.021–0.027 inches). Apply the paint to continuous façade surfaces without interruptions. It is advisable to get enough paint to ensure that continuous surfaces can be painted with paint from the same batch. Hide the working seams in corners, expansion joints or behind downpipes, for example. If you must use paint from different batches, use a 1:1 mixture of paint from the old and new batch where the batch changes. If the colour is strong or bright, you may have to apply an extra coat of paint. Clean the tools with water.
Dirty surfaces can be cleaned with a pressure washer. Repair any damages and fill any cavities. Repaint with Fescosan façade paint. One treatment suffices for a cleaned, undamaged surface. Priming with thinned Fescosan façade paint is also needed for damaged areas where paint has been removed or cavities filled.
If the product has been stored at a low temperature, it must be allowed to heat up to approximately +20°C before beginning the work. Air temperature and the temperature of the base to be treated must remain above +5°C for the entire drying period (3 days). High humidity, low temperature and poor ventilation extend the curing and drying period. Protect from rain.
Storage and handling of waste
See the separate storage and disposal instructions https://www.fescon.fi/en/material-bank