Clean terrace from concrete blocks

Our terrace (red concrete blocks) is almost completely darkened by algae. Now in the spring, before I put the garden furniture out again, it is cleaned like every year.

I do not want to use a high-pressure cleaner, otherwise sand, etc. land out of the joints in the bottom bar of my sliding door and we had no real success with other Grünbelagsentfernern. Special terrace cleaners are too expensive for me.

I need

  • 1 hard scrubber, hard brush for bottlenecks
  • 2 flat bowls (bucket too tight for scrubbers)
  • some bottles of vinegar cleaner (mine is from Al ..- South, small price)
  • recommended are rubber boots, gloves
  • old newspapers or rags

That's how it's done

  1. Always add a little of the cleaner undiluted to the first bowl (so do not fill it half or full with it) and work the stones with the scrubber until this small amount is used up, then refill with little.
  2. Because: if the stones should be colored (like our red ones), a larger amount of detergent is quickly discolored as well and you scrub the paint and especially the dirt back into the next stones to be cleaned. Is also more brash.
  3. Fill the second bowl with water up to the top and immerse the dirty scrubber from time to time, renew water several times. Wipe the detergent bowl in between with newspapers or rags. Heavily encrusted stones just dribble again with the vinegar cleaner and brush.

I have been doing this for 5 years now and am always happy about how clean the terrace has become. Without effort, you get in my opinion, such pollution not away. Maybe we'll have a white terrace soon? But free of lichens and algae ...

How to Clean Efflorescence Off Stone -- by Home Repair Tutor | February 2024