Save time, money and energy with these tips and pointers from someone who cleans windows for a living. Here's how to get streak-free windows every time.
10 Window Cleaning Tips from a Pro

Two scrubbers are better than one
Use two different scrubbers—one for inside and one for outside—so you don't carry pollutants and bird excrement inside.

Liquid dish detergent rules
Any kitchen dish liquid cleans dirt and grease and leaves the glass slippery so your squeegee glides well. A 100-percent biodegradable soap will protect sensitive plants outside. Inside it will protect toddlers and pets who put their mouth on the windows or sills.

Vinegar works, too

Oh, oh, oh it's magic
Mr. Clean Magic Eraser removes silicone caulk and water stains.

Dual-purpose paint can opener

New blade = no streaks
A 12- to 14-in. squeegee is a good size for most situations. Put in a new rubber blade after each cleaning to prevent streaks.

New blade = no scratches
A razor blade removes paint overspray and gunk. Keep the glass wet and use a new blade each time. Microscopic rust particles on the blade can scratch the glass.

Details matter
Carry two detailing rags—one for dirty jobs like sills and the other for detailing the edges of the glass.

Steel Wool for Tough Stains
If you need to remove tree sap, adhesive residue or other tenacious stains from your windows, try #0000 (4 ought) steel wool. Lubricate the glass with a spritz of window cleaner (Windex) and buff away the stains with a wad of super-fine steel wool.
Bring Out the Power Tools
Scrub away the toughest stains on glass with a small buffing wheel and a mild abrasive (Soft Scrub, Bar Keepers Friend or Bon Ami). When you’re working near the window sash, protect it with masking tape.
FAQ
Why is it important to clean your windows regularly?
Jon Riding, owner of Evergreen Cleaning Company says, “Keeping your windows clean does a lot more than improve your homes appearance.” He goes on to explain, “Over time, dirt, dust, and hard water spots can build up and actually damage the glass.” Cleaning windows is also a matter of health: “Regular cleaning can also help cut down on allergens like pollen and dust that can collect around the window frame and on the glass.”
How often should you be cleaning your windows?
Riding offers insight on how often you should be cleaning your windows. “For most homes, once or twice a year is sufficient. If you live near the ocean, a busy road, or somewhere with a lot of dust or pollen, you may want to clean them every three to four months,” he says.
About the experts
Jon Riding is the owner of Evergreen Cleaning Company, which specializes in eco-friendly, all-natural cleaning services.