How to Get Self-Cleaning Windows

If you could banish one home maintenance chore, would it be washing windows? Wishes do come true: A new type of glass actually breaks down and loosens dirt, minimizing spots and streaks with very little help from you.

Difficulty: Moderately Easy

Instructions

1. Determine whether self-cleaning windows are right for your climate. They work better in wet regions than dry ones because they require water to wash away dirt and grime.

2. Understand the chemical make-up of the glass:

3. The sun's ultraviolet light activates a durable, transparent titanium dioxide coating that is chemically fused to the glass. Even on cloudy days, the resulting photocatalytic action oxidizes organic dirt and loosens it from the surface.

4. Normal glass panes are hydrophobic (water repellent): Raindrops slide down, leaving behind dirt streaks and evaporated spots. Self-cleaning glass is hydrophilic: It forces water to spread out evenly in a sheet, washing away dirt loosened by the photocatalytic action. The sheeting action allows the window to dry quickly with minimal spotting and streaking. At night, the glass remains hydrophilic but loses its photocatalytic action.

5. Research self-cleaning glass through glass contractors and home improvement centers. Two manufacturers now offer self-cleaning glass: Pilkington North America (activglass.com) and PPG Industries' SunClean brand (ppg.com).

6. Do a cost-benefit analysis. Windows equipped with self-cleaning glass cost 10 to 20 percent more than windows with ordinary glass. Factor in the elbow grease and Windex, and you may have yourself a deal.

7. Plan when and where to install self-cleaning windows. When you're buying new or replacement windows, upgrade to selfcleaning glass particularly where access is difficult or dangerous: huge plate-glass or second-story windows, skylights, sunrooms and glass roofs.

8. Consider combining self-cleaning glass with low-emissivity (insulating) and solar-control glazing to save energy costs as well as cleaning time.

Tips & Warnings

• During dry spells, you'll need to give a light spray with the hose to rinse the exterior of self-cleaning windows. Also, the glass won't shed any inorganic matter--paint spatters, for example.

on 6/30/2006 Cover one end of the rod with a plastic bag. This will smooth out the uneven pieces of metal that catch on the curtains, particularly lace and sheers. Slide the curtain onto the rod. Remove the plastic bag. Curtain and rod are ready to be hung.

on 11/22/2005 This is a tip and a question.
Here in New Zealand we hang lace curtains on a plastic covered wire with two hooks in the ends. This is stretched tightly between two metal loops. The normal routine is to attach the hooks to the wire (which is then threaded through the top fold of the curtain) and have the loops in the woodwork. However, when you take the wire out of the curtain to launder, the hooks often catch on the lace or nylon. I reverse the process, putting the loops in the wire and screwing the hooks into the woodwork. Pulling the wire with loops on, doesn't catch the curtain fabric. This is especially useful when the hooks and loops rust slightly (don't ask me why they can't make these things of non-rusting material).

on 11/22/2005 The term "self cleaning glass" has been found by SU Glass magazine and British governing offices to be a false claim. The term low maintenance, or low-m glass, is to be used instead. The low-m glass does not have to be a replacement product. Several companies offer it for on site application to existing glass, such as Hydroshield, Clearshield, and Diamond fusion. They generally charge between 900 and 1500 U.S. dollars a gallon. But, after much research, I have found that the same product has been available for airplanes since the seventies.