Expert: Robert Lamb - 8/23/2010

Question
I had my bathroom complete redone 2.5 years ago, including adding glass shower doors.  I have tried to squeegee them every day (but being human, often do it only 3 or 4 times a week).  We live in a very hard water area and the lime scale has built up considerably.  The cleaners recommended by the company just don't work and yet they say that using abrasive cleansers, steel wool, etc. will eventually ruin the glass as it is porous and has a treated film over it.  I've tried everything on the stronger end of the list, but nothing will get these millions of little lime scales off.  They don't recommend CLR or anything like that, any abrasive cleansers.  Any ideas?  Rebath did our installation and it is great....they recommend their own cleaner for the tub surround, which is great, but is useless on the glass with buildup.  Any ideas would be appreciated!  Thanks

Answer
Sue,

Using a squeegee daily on shower stalls is a good idea. I do that too. But with hard water, you are almost always going to have some problems. Glass is porous. The people that told you that were correct. As far as a treated film placed over the glass, I have never heard of such a thing. Besides, it doesn't seem that this film is doing it's job.

Here's my suggestion. To remove hard water spots from glass, you will need to use a restoration method professional window cleaners use. The two methods are chemical and mechanical.

Chemical: The most effective method, and the one I would recommend, is to use a chemical or chemical formula (most are acid based). You can start at the milder end of the scale using something like Sani-Scrub, A1 Hard Water Stain Remover, Bio Clean Water Stain Remover, MDR, Unger RubOut, Safe Restore, Sorbo Hard Water Stain Remover, etc.

With the damage you describe, you may need a harsh acid like hydrofluoric acid. This is extremely corrosive and dangerous to handle though. See the Wikipedia article at http://tinyurl.com/yhbura CC550 is one of these chemical formulas that contain hydrofluoric acid. When working with hydrofluoric acid, always read and follow the instructions and use safety goggles, gloves and avoid getting this on your skin.

There are window cleaning warehouses that sell these items especially for this purpose. We use ABC Window Cleaning Supply (http://tinyurl.com/ykl37gy), but there are other fine suppliers like J Racenstein (http://tinyurl.com/yfaeqdm).

The process is to put a small amount of chemical on a white pad (3M makes these) and put the pad on the glass in an out of the way area to test it on the glass. These scrub pads are graded according to abrasiveness and white is safe for glass.

The best is yet to come. A new cleaning formula is now available that reportedly is much easier to use and will also seal the glass after it is cleaned. It's called Nano Technology. If I were you, I would first try this formula to clean and seal your shower stall glass. This is a direct link to one window cleaning supply house that sells this product: http://tinyurl.com/374ssjd

Mechanical: Use an abrasive on glass like steel wool. By the way, steel wool won't scratch glass unless the steel wool is rusty. On a Mohs scale (http://tinyurl.com/sqg8q) steel (as in steel wool) is softer than glass. Rust on the other hand, is an abrasive that is higher on the Mohs scale than glass. Some window cleaners buffing off the glass using an abrasive like cerium oxide commonly called "jeweler's rouge". The process can be dramatically expedited by using a power buffer or drill.

I hope this helps. Please let me know if this has resolved the problem.

I would love hearing how your problem was resolved.

Sincerely,

Robert Lamb
Window Masters
www.mywindowmasters.com
Rob's Window Cleaning
www.robswindowcleaning.com