The Best Way to Clean Windows: A Step-by-Step Guide to Get a Streak-Free Finish Every Time

Being a cleaner isn't that hard, right? Anyone can do it. While, admittedly it’s not rocket surgery, people usually find that it’s harder than it looks. A lot of people wonder what is the best way to clean windows. Anyone can use Windex, but it’s nowhere near as efficient, cost effective, or professional as cleaning them properly. It also doesn’t leave as good a result. The product can leave a build-up. making the glass appear foggy and the cloth can leave behind lint and streaks. The best way to clean windows is with a T-bar and squeegee. This takes a bit of practice to get right, but you will save time and money on expensive glass cleaning products in the long run. Plus you will look, and feel, like a pro. If you’re not a professional cleaner, you can impress your family and friends with your newfound skill. Invite them around and happen to be cleaning your windows when they arrive. When they ask what you’re doing you can nonchalantly say, “oh I’m just cleaning the windows, no big deal.” They’ll be impressed at your prowess.

So why won't Windex cut it?

The reason you can’t just clean a window with a wet cloth the way you would your kitchen counter is because the water that comes out of your tap is not pure. It’s rich in minerals and additives (See our article here for a discussion of water hardness). When the water evaporates it leaves behind these particles and any dirt that your cloth has picked up, showing up as a dirty streak on your window. If you had pure water, (less than 50 ppm) you could just hose off a window and be done with it, and in fact that is what some window cleaners do with what is called a water fed pole. As that equipment is expensive and bulky, we will stick with the squeegee. It serves our purpose nicely and, as I mentioned, makes you look cool. The squeegee rubber effectively dries the glass before the water gets a chance to evaporate. So the key thing is that you get all of the water, before it evaporates, otherwise you will leave streaks.

What you'll need

A T-bar – This is the handle part that is used for washing the windows. (So named for its “T” shape).
A T-bar head – The T-bar head (or mop) is the, usually microfibre, fabric cover for the t-bar. It is very absorbent and so deposits a good amount of water on the glass. The T-bar and T-bar head can be replaced with a cloth or sponge if you don’t want to invest too much money initially.
A squeegee – No need to go overboard when buying your first squeegee. You can get a lot of different types and qualities of squeegees. Window cleaners love to tell you about the best brands, but you don’t need to worry about that now. Just an affordable squeegee will do.
A bucket, half filled with water – A window cleaners bucket is long enough to fit your T-bar and squeegee in.
Detergent – Standard dishwashing detergent, whatever you’re already using on your dishes will work fine. We use eco-friendly brands as it’s less harsh on your skin and better for the environment.
A towel – An old towel you have in the rag cupboard. Alternatively pick up one for a few dollars from the second-hand store.
A rag or cloth – Use this for wiping off window sills and frames and drying your squeegee between strokes.
A microfibre glass cloth. – A tightly weaved microfibre glass cloth specifically designed for wiping glass without leaving streaks. Only for the edges.
A track brush (optional) – A very useful tool if you want to loosen and remove dirt trapped in your window tracks.

What you'll need to do

Window Tracks, Screens and Frames

Cleaning the window tracks, flyscreens and sills or window frames first is a good idea so that dirt doesn’t get on your windows once they’ve been cleaned.

Brushing down the flyscreens on both sides with a dustpan brush may be sufficient, depending on how dirty they are. Otherwise, wiping them down with a damp cloth or towel will get them clean without releasing any dust into the air.
If you’re going to clean the window tracks, now is the time to do it. We find that the brushes specifically designed for cleaning window tracks work the best and don’t deteriorate as quickly.. They’re available from your local hardware store, although you can use a dustpan brush or a paintbrush if it’s easier for you. Use the brush to loosen up any dirt in the track and follow it with the vacuum nozzle to suck up the dirt. I have the brush in one hand and the vacuum nozzle in the other hand to save time. If the tracks are quite grimy, a damp cloth should get off any stubborn dirt that the brush won’t. Do the tracks first because if the tracks get wet then any dirt in the track will no longer be loosened by the brush and the brush/ vacuum combo won’t work.
Then, finally give the frames a quick wipe with your rag, it doesn’t matter if you smudge the windows as they’re still yet to be cleaned. If you leave this til after cleaning the windows then you’ll have to be very precise to avoid smudging your nice clean windows.

Wash the window

Start by laying down your towel/sheet at your first window. When you’re squeegeeing, your squeegee will drip water onto the sill and tracks. That is what the towel is for; to catch any drips that are going to fall. Pro tip: if there is a window track underneath the window, then stuff the edge of the towel into the track. This will stop it falling off the window sill and stop the track from getting wet. If there is no track, it may require some careful folding of the towel so it doesn’t fall off the sill.
Next, dunk your T-bar in your bucket and wring it out so that it’s wet, but not dripping.
Apply a few drops of detergent to the t-bar head. I usually put one small drop on each end and one in the middle. You’ll get a feel for the right amount to use with a bit of practice. You want an even bubble pattern on the glass. If the bubbles are too thin, then add more detergent to your t-bar head or wring out more water.
Give the glass a good scrub with the t-bar. Anywhere that there are stubborn marks such as grubby finger prints or stuck on dirt, apply a bit more pressure.

Squeegee the glass

When you’re starting out, it’s always better to keep it simple. We recommend using ‘straight pulls’ (left to right or up to down) with your squeegee. The pros will use the fancy ‘S’ technique, but this is difficult to master until your squeegee skills are on point.

Work out which way to do your squeegee strokes; either up to down or side to side. Go with whichever option means the least possible strokes and avoids any obstructions as much as possible.
You want to hold your squeegee about 45 degrees to the glass and keep this angle consistent the whole length of the stroke. Do this by moving your body, rather than your arms or wrist. If you place the squeegee on or remove it in the middle of the glass you’ll leave, you guessed it, streaks. You will also need to dry your squeegee off between each stroke with one of your rags. Do not use a glass cloth to dry your squeegee as you want it to stay as dry as possible. Once the glass cloth gets wet it will leave streaks on glass.
If, for example, you’re doing strokes from top to bottom, put your squeegee on the top edge of the glass right in the left hand corner, as close to the frame or seal as you can get it. Then you want to do ‘false starts’ on the top inch of the glass dragging down about an inch and replacing the squeegee at the top and repeat until you don’t see any soap bubbles on that top inch. This ensures that you get a clean start and don’t drag any soapy water when you start your stroke.

How did you go?

Have a look at your stroke, did you run up the edge at all? Did you lift up the squeegee anywhere? To see a streak you need to check from the right angle, with a light source behind the streak. You need to move around and drop down low or you won’t be able to see them. If there is water anywhere on the stroke, aside from a thin strip around the edges, then stop and think why that happened. Soap it up and do it again, this time without the mistake. That way you’re correcting any errors in your technique, rather than practising incorrect technique. Don’t be tempted to use your glass cloth on drips or streaks on the glass. Your glass cloth is only for the edges of the glass that the squeegee can’t get to. If you use it on the glass. it will look like you’ve gotten away with it, but electrostatic charge will transfer to anywhere you touch on the glass, and that will attract dust and lint from the air, anywhere from half an hour to a few hours afterwards it will be obvious where you’ve touched it.

Rinse and repeat

On to the second stroke. Dry your squeegee off with a rag (not a glass cloth) between each stroke and repeat the process. You want your squeegee to overhang your previous stroke by roughly one third. Angle your squeegee very slightly down towards the part that you’ve already cleaned, this prevents you from leaving a line at the end of your squeegee. For this stroke you won’t be against the edge, so you want to watch that left edge of the squeegee again. Make sure that you remain overhanging into the previous stroke by about one third of the squeegee and that your angle remains pointed very slightly downward. Once you complete the stroke, stand back and check your work from every angle. If there are any streaks or drips. soap the area and do it again.
Repeat this process, drying your squeegee between each stroke (with a rag, not a glass cloth), until you get to the edge of the glass. When you get to the final stroke you may have an awkward amount of glass left to clean. If it isn’t roughly two thirds the length of your squeegee, soap it up so that it is as you don’t want your squeegee rubbing on dry glass, that will prematurely expire your rubber. Then repeat the technique for the first stroke, again using the frame or seal as a guide, keeping the edge of the squeegee as close as you can to the edge without running up it and a very slight downward angle toward the glass you’ve already cleaned.

If you have to redo a lot, (which you probably will on your first time) then the glass you’ve soaped up already may dry out (how quickly it dries out will depend on the weather) just soap it up again to ensure you have enough moisture for your squeegee to glide.

Final touches

What you should be looking at is a sparkling clean window with a thin bead of water around the edge. Great! Now is the only time you will use your glass cloth. Extend your index finger and put the glass cloth over the end of it. The width of your finger should be enough to dry the bead around the edge (at most two fingers). Start with the top edge as it can start to drip down onto your glass. Go slowly and watch carefully that all the water is being collected. Then I do the two side edges. The bottom edge, especially if it is an external window, can often be quite dirty, so you may want to use a towel or rag for that edge to keep your glass cloth clean.

Wipe off your sill and hey presto! One window finished. As I said at the start, window cleaning is one of the more difficult cleaning skills to master, but like all skills, you’ll get good at it with practice.

So with each stroke make sure you’re doing the fundamentals correctly (even pressure, good contact. smooth movement), check your work and think about how you could do it better. After a while you’ll be window cleaning like a pro. Now that you know the best way to clean windows, go forth and spread the word!