This is probably a window cleaner and home owners worst nightmare when it comes to window cleaning. But believe it or not there are a few simple techniques and tips to keep in mind before placing that steel razor blade on that precious glass of yours. So if you’re a home owner about to tackle your own windows or a new window cleaner you may want to take notes.
First of all, know what kind of glass your windows are made of. Tempered glass is extremely easy to scratch, I won’t even touch a razor to it. How can you tell if your glass is tempered? Usually you can see a small etching in the corner of the glass that will tell you if it is or not. Not all windows in a house will be tempered but it’s always best to check just to be safe.
Once you’ve checked to see if it’s tempered glass or not, another thing to keep in mind is that not all windows need to be scraped. I personally only use a razor blade if absolutely necessary. If there is debris that won’t easily come off easily I prefer to use grade #0000 steel wool, it’s abrasive enough to take off hardened dirt, construction debris and even tape without scratching the glass. But even with steel wool there is a risk. If you choose to use it be sure it is grade #0000, the least abrasive grade. Also, be sure to clean off the loose dirt from the window first and never use it against a dry window. Keep in mind too that since it is steel and you will be getting it wet it will rust so try to keep it out of the sun so that it last longer.
Okay, so you know it’s not tempered glass and you’ve tried steel wool but there is still that pesky piece of tape that won’t come off. Now is when I pull out my razor. First thing I do is make sure I have a fresh blade, a rusted or dull blade could scratch the glass. Next, just like with the steel wool, never use it against a dry window, make sure the glass is wet and rinse the blade often. When scraping, and this is the most important part, only move the blade in a forward motion! Most of the time someone scratches a window is because they move the blade back and forth repeatedly. It’s not actually the blade that scratches glass, but dirt caught in between the blade and the glass. When the blade is moving forward dirt is being separated from the glass and pushed onto the razor, but when you move it backwards the dirt gets wedged in between the razor and dragged across the glass leaving a nice big permanent scratch for you to remember it by. So never drag the blade backwards but lift it up before scraping the window again.
Keep these tips in mind before cleaning your windows and you will enjoy clean scratchless glass every time. And if you decide that you need to have them cleaned professionally make sure you hire someone who knows what they’re doing.