Stains, Mopping, Wiping, Ironing, Cleaning/cleaning



I forgot to wipe out a very long line of grout when re grouting in the backyard.  It got really hard...

Is there any good way of removing this hard grout from the slates?

Thank you very much,   Gabe

Generally, you may be able to use a grout cleaner (acidic) and let it set to soften it and then try carefully scraping it down. It will be tedious work, there is no simple/easy solution.
A product such as Aquamix or Sulfamic acid works pretty well. Please spot test your slate before hand as some slate will pit. You will probably have to use it full strength. Try to keep your solution on the grout itself. Agitate it with a nylon pad or brush such as a stiff nylon brush or deck brush when you put it on, and then let it sit for 5-10 minutes or longer and may have to keep re wetting. You may also have to use a scraper. Do a small area at a time.
Don't forget to neutralize the cleaning process when you are done such as with a baking soda and water rinse.

NOTE: Some professionals use muriatic acid. It will usually soften grout very well and will come off with a putty knife.  HOWEVER its messy and nasty and can easily burn your skin and the vapors can be harmful ESPECIALLY indoors.  

Stains, Mopping, Wiping, Ironing, Cleaning

All Answers

Answers by Expert:

Ask Experts


R Adams


3m Certified carpet cleaning instructor can answer questions regarding spots/stains on carpet and other floor coverings and possible ways to remove same. Can also answer questions with regard to upholstery cleaning. I do not recommend specific name brands, companies or products.


10 years as a Former 3M Certified Carpet Cleaning Instructor. Certified flooring inspector for major mills 1985-present.

Floor Covering Inspector Training School; FCITS Floor Covering Inspection Technical Services; FITS Certified Claims Inspectors Association; CCIA

Hartford Courant

B.S. Chemistry 1971 A.S. Physical Science 1969 Armstrong Certified Installer 1972 3M Certified Carpet Cleaning Specialist 1976 FCITS Certified in Carpet and Hard Surface, Commercial and Residential

Past/Present Clients
GE, Phoenix Insurance Group, McDonalds Corp, WTNH, US NAVY, Xerox, Time Warner, Pitney Bowes, Conair, Yale New Haven Hospital, UCONN, Price Waterhouse, PepsiCo

©2016 All rights reserved.