How to clean windows without streaks, inside and out

The short answer: how to clean windows without streaks is mostly technique and timing, not expensive products.

• Pick a cloudy day
• Clean the frames first, then the glass from the top down
• Squeegee across the glass and polish off any moisture
• Reach high windows safely from the ground
• Next step: Plan it with the Cleaning Schedule ($4.49).

Knowing how to clean windows the right way saves you from the most frustrating part of the job: finishing, stepping back and seeing streaks. The fix is mostly technique and timing, not expensive products. This guide walks through the supplies, a simple homemade cleaner, the squeegee method Consumer Reports recommends, frames and tracks, paint spots and how to reach high windows safely from the ground.

How to clean windows: the quick version

1. Pick a cloudy day, or work on windows that are in shade.
2. Take down or tie back curtains and clean the frames first.
3. Start at the top and apply cleaner with a slightly damp sponge.
4. Squeegee across the glass and wipe the blade after every pass.
5. Rinse with a chamois and clean water.
6. Polish off any moisture with a dry, lint-free cloth.

What you need

Consumer Reports' window cleaning guide lists a short set of supplies:

A couple of microfiber cloths are handy too. For high outside windows, you'll also want a telescoping pole, covered below.

Choose the right cleaner

The cleaner matters more than you might expect. In Consumer Reports' past window tests, CR found it's easy to stain some brands of windows with the wrong cleaner. Ammonia-based formulas, including some Windex products, can cause streaks or film. Before you start, check your window manufacturer's website for its cleaning instructions.

Two simple options that avoid ammonia:

• Vinegar spray for inside windows. Consumer Reports' guide to cleaning with vinegar cites window maker Pella, which advises mixing one part distilled white vinegar with 10 parts warm water in a spray bottle.
• Bucket mix for outside windows. CR's guide to high windows suggests a large bucket of water with several generous squirts of liquid dish detergent and vinegar, or a store-bought ammonia-free window cleaner.

Keep vinegar solutions off wood, fiberglass and vinyl frames. CR warns the vinegar may discolor the finish.

Step 1: Pick the right time

Wash windows on a cloudy day or when the windows are in shade. Consumer Reports explains that direct sun makes the cleaning solution evaporate before you finish, and that's what causes streaking. If you have a lot of windows, CR suggests splitting the job into segments rather than trying to clean them all in one day. One side of the house each weekend works well.

Step 2: Prepare the room

Take down your curtains or loop them over a hanger, out of the way. CR notes it's a good time to clean them, too. Move furniture back from the window, and lay an old towel on the sill to catch drips.

Step 3: Clean the frames first

Clean very dirty frames before the glass, so grime doesn't run onto clean panes.

• Aluminum frames and doors: vacuum the runners, then polish the frames with silicone car polish. CR says the polish can also be used in the channels to help windows slide smoothly, or you can lightly oil the channels.
• Painted or vinyl frames: wash with a sponge dipped in warm water and detergent, rinse with warm, clean water and towel dry if needed.

Step 4: Wash the glass from the top down

This is the method Consumer Reports recommends:

1. Dip a sponge in your cleaning solution and squeeze it so it's only slightly damp.
2. Wash the glass starting at the top.
3. Wipe across the window with a dampened squeegee blade.
4. Wipe the blade on a cloth after each swipe.
5. Rinse with clean water applied with a chamois.
6. Polish off remaining moisture with a dry, lint-free cloth.

Working from the top down keeps dirty drips from running over glass you've already cleaned.

If you're using the vinegar spray instead, CR suggests wiping the window with a clean microfiber cloth to remove dust first, then spraying the whole surface, wiping it clean and drying it as thoroughly as you can with a second clean microfiber cloth.

Step 5: Use tilting sashes for the outside

Most newer double-hung windows have tilting sashes, which let you pivot the window inward so you can clean the outside from inside the house. On most, you just flip a lever to tilt the sash in. On some, you have to pull the sash out of the track. Check your window's instructions if it doesn't move easily.

How to clean high windows from the ground

Upstairs windows that don't tilt in are the trickiest. Consumer Reports says one of the most effective ways is a telescoping pole fitted with cleaning heads like brushes, sponges and squeegees, and that a pole is much safer than standing on a ladder.

Before you start, CR suggests:

• Look for wires. Make sure the pole won't touch any electrical wiring.
• Check the windows. Use binoculars to make sure panes and frames are intact, and look for putty, paint or cracks that need repair.
• Clear the ground. Remove brush, stones and anything else you could trip over.
• Test the pole. If it's too unwieldy, hire a professional window cleaner instead.

To clean, dip the sponge or microfiber head in your bucket and scrub the window, rinsing and squeezing it out as you go. Then attach the squeegee, start at a top corner and drag it down to the bottom of the pane, wiping it after each swipe.

How to get paint off window glass

If you've been painting, Consumer Reports suggests:

• Fresh water-based paint: a cloth dipped in water or glass cleaner.
• Fresh oil-based paint: a cloth dipped in turpentine.
• Old, dried paint: a single-edged razor held at an angle so it doesn't scratch the glass.

Leave about 1/16 inch of paint along the edge of the glass. CR says it protects the frame from condensation inside and rain outside.

Special windows

• Stained glass and small windows: wipe with a damp sponge, then a clean damp chamois, and polish with a clean cloth. Treat delicate stained glass gently, and clean painted glass only with a damp chamois.
• Skylights: some can be reached with extension tools, but CR says it may be more practical to hire a professional for out-of-reach windows.

How often to clean windows

CR says the insides of windows usually need cleaning twice a year, while the outside depends on your location.

Common streak causes

• Sun on the glass dries the cleaner too fast.
• A dirty squeegee blade drags grime back across the pane.
• Ammonia-based cleaners can leave streaks or film on some windows.
• Linty towels leave fibers behind. Use lint-free or microfiber cloths.
• Starting at the bottom lets drips run down over clean glass.

A window cleaning plan for the whole house

If you're cleaning every window at once, a simple plan keeps it from taking over a weekend:

1. Make a list of rooms and count the windows in each.
2. Gather the supplies in one caddy: two buckets, a sponge, a squeegee, a chamois, lint-free cloths and your cleaner.
3. Group the windows by side of the house, so you can work on the shaded side and follow the shade.
4. Do the frames and tracks first in each group, then the glass.
5. Do the insides on one day and the outsides on another, or tilt the sashes and do both together.
6. Wash curtains while the windows are bare.
7. Note any repairs you spot, like cracked glass, loose putty or peeling paint.

Consumer Reports' advice to divide the job into segments is the key. Two or three windows done well are better than a whole house done in a rush with streaks.

Window cleaning checklist

• Curtains down or tied back
• Frames and tracks vacuumed and wiped
• Glass washed top to bottom
• Squeegee wiped after every pass
• Glass rinsed and polished dry
• Sills wiped
• Repairs noted

Put window washing on your seasonal list

Windows are a twice-a-year job, which makes them easy to forget. Our Cleaning Schedule ($4.49) is a 9-page printable with daily, weekly and monthly checklists, a seasonal deep clean list, room-by-room checklists, a family chore chart and a cleaning supplies list. Put "wash inside windows" and "clean curtains" on the spring and fall lists, and add a squeegee and vinegar to the supplies page.

Doing a whole room? See how to clean blinds for the slats while the windows dry.

If you'd like to get the whole home organized at once, the Home Management Bundle ($16.99) includes the Cleaning Schedule along with the Household Binder, Home Maintenance Log, Home Inventory, Moving Planner and Password & Accounts Log. Bought separately, those six come to $32.94.

For the rest of your seasonal cleaning, see our deep cleaning checklist and our cleaning schedule template.

Your next step

Pick one room and wash its windows on the next cloudy day: frames first, then the glass from the top down with a squeegee and a dry cloth to finish. Once you see how quickly one room goes, plan the rest of the house in segments over the next few weekends.