Cleaning windows is one of those tasks that looks simple until you step back and find the glass covered in streaks that somehow look worse than before you started. The good news is that streaky windows almost always come down to technique and timing rather than the product you're using.
This guide covers exactly what causes streaks, the right order to clean in and the mistakes most people make that are easy to avoid once you know what they are.
Why Windows Streak in the First Place
Understanding why streaks happen makes it much easier to prevent them.
The most common causes are:
- Cleaning in direct sunlight - the solution dries on the glass before you can wipe it off, leaving residue behind. This is the single biggest cause of streaking for most people
- Too much product - excess cleaning solution takes longer to remove and increases the chance of residue
- Dirty tools - a cloth or squeegee that's carrying residue from a previous pass will redistribute it straight back onto the glass
- Wrong cloth material - paper towels and regular cloths leave lint on glass. Microfibre is the right tool for windows
Fix these four things and most streaking problems disappear before you've changed anything else.
What You'll Need
- Two microfibre cloths - one for washing, one dry for buffing
- A squeegee for larger windows
- A bucket or spray bottle
- Mild dish soap or white vinegar
- A soft brush or dry cloth for frames and tracks
For your cleaning solution, Bunnings recommends a simple mix of water, a small amount of dish soap and white vinegar - you can read their full window cleaning guide at bunnings.com.au. It's genuinely one of the most effective solutions for most home windows and costs almost nothing to make.
Avoid ammonia-based or heavily alcohol-based products - they can leave a thin film on glass that actually attracts more dust and moisture over time.
The Right Order to Clean Windows
1. Start with frames and tracks - not the glass
This is the step most people skip. Frames and window tracks accumulate significantly more dirt than the glass itself, and if you clean the glass first that dirt transfers straight back during the process.
Use a dry microfibre cloth or soft brush to wipe down frames, seals and tracks before touching the glass. For particularly grimy tracks, a damp cloth followed by a dry one works well.
2. Choose the right time of day
Never clean windows in direct sunlight or on a hot day. The solution evaporates too quickly and leaves residue before you can remove it. Early morning, late afternoon or an overcast day gives you enough time to work the solution properly before it dries.
3. Dry dust the glass first
Before applying any liquid, wipe the glass with a dry microfibre cloth to remove loose dust and debris. Applying solution over dry dust turns it into a paste that smears rather than lifts. This one step makes a noticeable difference to the final result.
4. Apply solution and wash the glass
Spray your cleaning solution onto the cloth rather than directly onto the glass for interior windows - this gives you more control and prevents drips onto walls and floors. For exterior windows, spraying directly onto the glass is fine.
Work from the top of the window down using straight horizontal strokes. Don't scrub in circles - straight strokes are easier to track and less likely to leave swirl marks.
For larger windows, apply the solution with a damp microfibre cloth or sponge applicator, working the solution across the entire pane before moving to the drying step.
5. Squeegee technique
For larger windows a squeegee is the most efficient way to remove solution without streaking. The key details most people get wrong:
- Start at the top corner and pull straight down in overlapping passes
- After every single pass, wipe the squeegee blade with a dry cloth - a wet or dirty blade redistributes residue onto the next section
- Overlap each pass slightly to avoid missed strips
- Work at a consistent angle - around 45 degrees to the glass
For smaller windows and interior glass, a dry microfibre cloth buffed in straight strokes from top to bottom works just as well without the need for a squeegee.
6. Buff the edges
After the main glass is done, go over the edges and corners with a dry microfibre cloth. These areas accumulate drips and residue from the cleaning process and are where most remaining streaks appear after everything else looks clean.
Step back and check the glass from an angle under natural light - this reveals streaks that aren't visible when looking straight at the glass.
Common Mistakes That Cause Streaks
- Using paper towels - they leave lint and fragments on glass. Always use microfibre.
- Too much soap - a small amount of dish soap goes a long way. Excess soap creates more residue to remove and increases streaking.
- Not wiping the squeegee between passes - this single habit change makes the biggest difference to squeegee results.
- Cleaning on a hot sunny day - as covered above, this is the most common reason for streaking even when technique is otherwise correct.
- Reusing a dirty cloth - once a cloth has picked up significant residue or grime, it starts redistributing rather than removing. Have a second clean cloth ready.
How Often Should You Clean Your Windows
For most Sydney homes, twice a year is the realistic minimum for a thorough window clean. Homes closer to the coast, near main roads or in dusty areas will benefit from more frequent cleaning - coastal salt and road dust accumulate on exterior glass faster than most people expect.
A quick wipe of interior glass with a dry microfibre cloth between full cleans takes a few minutes and keeps the standard up without a full clean every time.
When Professional Cleaning Makes Sense
High or hard-to-reach windows, heavily built-up exterior glass or simply not having the time to do it properly are all reasonable reasons to book a professional clean. For professional home cleaning across Sydney including detailed interior window cleaning as part of a regular service, visit our general cleaning page.
