Anyone have any ideas about how to get dried limestone cement off a garage door?

Question

The garage door is the 'cedar' look and the limestone has been left to dry for a good while!

Answer 1

I had some on a door for about fifteen years and was able to get it wet, saturated and pop it off of the metal door. The water helped break it loose.

Answer 2

I have some suggestions.
The lime based cement is alkaline and the right thing to remove it will be an acid. The professionals use hydrochloric acid to clean bricks for example but this is extremely corrosive and should be a last resort, with protective equipment. (It may also mark the door)
Vinegar is an acid but not as strong and may help to soften it gradually. Be patient.
Paint a bit of white vinegar on a small section of the cement several times times over a few hours.
See if it causes the surface to become crumbly at all compared to the rest.
If this works, paint ot over the affected areas repeatedly until they are softened then use a pressure washer to clean it off.
You may need more vinegar with a cloth to finish the job.
Note: The cement may have marked the surface in which case it will need re-painting.
If the cement is very concentrated it may be a match for vinegar and it may need the strong stuff. Carefully.


Good luck