Clean exterior plaster regularly and gently

Age and weathering are increasing in size over the years. It fades out, absorbs dirt particles from the air and can be attacked by organic stain formers such as mold and moss. When cleaning, the strength and type of plaster must be observed. Not all auxiliary devices work effectively and at the same time gently enough.

Few and effective tools

The exterior plaster as a building skin gets all the everyday dirt that is carried through the air. This may include organic spores that cause algae, moss and mold. Second major cause of pollution is fading and denting. If mechanical damage, such as crumbling plaster, is discovered, it must be repaired and remediated before each cleaning.

Since outside plaster is usually heavily watered when cleaning, the outside temperatures should be between ten and 25 degrees Celsius. Mechanically rubbing action is preferable to blasting with high pressure. Serve as aids and tools:

  • High pressure cleaner (with adjustable pressure and not over 150 bar)
  • Long-handled brushes
  • Water hose with spray nozzle
  • vinegar
  • washing soda
  • potassium permanganate

The three cleaning additives vinegar, soda and potassium permanganate are added to the water in small quantities (about one tablespoon to five liters). They dissolve organic build-up on the exterior plaster.

It is always cleaned from top to bottom in order to completely eliminate run-off wastewater runoff. Scratch plaster and rough plaster can be removed by soaking and structural direction brushing of dirt deposits. Soaking for up to a quarter of an hour increases the effectiveness of the enclosed cleaning aids.

Ladders, scaffolding and short distances

The best and at the same time the most gentle result when cleaning facades is achieved by handwork. This requires a good approach, even at higher altitudes. When cleaning with a brush and / or high-pressure blaster, short distances allow a very controlled amount of force to be applied to the exterior plaster. To clean the exterior plaster of a facade, the following aids should be considered:

  • full frame
  • Electric work and lifting platform
  • Rollable work platforms

All aids can be lent in specialist stores, equipment rental companies and in the building materials trade. Ladders are only conditionally suitable because they do not provide sufficient stability and can lead to damage to the plaster at the leaning points.

Tips & Tricks

When using a high-pressure blaster, always try to find out whether the building skin can tolerate the radiant power and, if necessary, heat, on an inconspicuous plaster surface.

Artikelbild: hermaion / Shutterstock

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