Window cleaning looks like the simplest job in cleaning and it is one of the few that punishes you instantly for getting the method wrong. Spray, wipe, stand back, and there they are: streaks across the middle, a smear at the top, and a haze that only shows up when the afternoon sun comes around.
The fix is almost never a better spray. It is method, order and a couple of pieces of gear that cost less than a bottle of premium cleaner. Here is how it is done properly.
What this covers
Why windows streak in the first place
A streak is residue. Something has been left on the glass and then dragged around instead of removed. In practice it comes from one of five things:
- Too much detergent. More soap does not mean cleaner glass; it means more film to remove. A few drops in a bucket is plenty.
- Not enough water. Dirt has to be lifted off and floated away. A dry cloth on dusty glass grinds the dirt into a smear.
- Cleaning in direct sun. Hot glass dries the solution before it can be removed, and whatever was suspended in it stays behind.
- A tired squeegee blade. Rubber nicks and hardens. One small nick puts one thin line down every pane you touch.
- A saturated cloth. Once your microfibre is wet through, it stops absorbing and starts redistributing.
There is a sixth, and it is the one people waste the most time on: the mark is on the other side. Clean the inside with horizontal strokes and the outside with vertical ones, and you will know instantly which face to go back to.
The kit that actually matters
- A bucket and a few drops of dishwashing liquid. That is the solution. Professional window suds exist and are slightly better on lubrication, but plain dish soap in cool water works.
- A T-bar washer with a microfibre sleeve. This is the piece most homes are missing. It holds far more water than a cloth and it agitates the whole pane in one pass.
- A squeegee with a fresh rubber blade. Blades are consumable. Replace or flip the rubber when it stops cutting cleanly.
- Two lint-free microfibre cloths. One damp for frames, one bone dry for detailing edges and corners.
- A soft detailing brush and a vacuum for tracks and sills, used before any water appears.
A scraper has a place for isolated paint or adhesive spots on plain float glass, used wet and at a shallow angle. It has no place on tinted, coated, textured or toughened glass, where it can leave permanent marks. If you are not certain what the glass is, do not use a blade on it.
The method, step by step
- Dry first. Vacuum or brush the tracks, sills and frame edges. Grit is the enemy — wet it and it becomes mud that runs back down your clean glass.
- Wash generously. Load the washer, start at the top, and cover the whole pane. Push into the corners and along the edges, where the dirt actually lives.
- Squeegee with overlap. Straight pulls from top to bottom, each one overlapping the last by a few centimetres, and wipe the blade dry between passes. On large panes, the S-shaped fan stroke does the same job in one continuous movement — worth learning if you have a lot of glass.
- Detail the edges. Run a dry microfibre around the perimeter where the blade could not finish. Fold it into quarters so you always have a dry face to turn to.
- Frames and sills last. Damp cloth, then dry. Doing them first means dirty water runs back onto finished glass.
- Check on an angle. Step to the side and look across the pane rather than straight through it. Film and missed edges only show up in raking light.
That is the whole technique. The order is what makes it repeatable: dry work before wet work, top before bottom, glass before frames.
Timing and Melbourne weather
Early morning, late afternoon or an overcast day. On a hot, bright day the sunlit side of the house will dry faster than you can squeegee it, so work the shaded elevations and come back to the rest — or just pick a cooler day.
Two Melbourne-specific things are worth planning around. Spring pollen leaves a fine yellow film that shows up badly on glass, particularly on north-facing windows and anything near a park or nature strip, so late spring is usually the busiest time for residential glass. And a long dry, windy spell coats road-facing windows in fine grit — that is the situation where washing generously first, rather than wiping, really matters.
One myth worth retiring: rain does not undo a window clean. Clean glass with clean rain on it dries clear. What leaves the spotted mess is rain landing on dusty glass, or rain running off a dirty gutter or awning and down the pane. If your windows look terrible after every shower, the problem is above the window.
Tracks, screens and sills
This is the part that separates a real window clean from a quick wipe, and it is what agents and clients notice.
- Tracks: vacuum with a crevice tool, work the corners with a stiff brush or an old toothbrush, then wipe with a damp cloth wrapped around a flat blade or a screwdriver to reach the channel. Dry afterwards.
- Flyscreens: lift them out where they come out easily, brush both faces with a soft brush, rinse gently and let them dry fully before refitting. Do not scrub — the mesh stretches and pops out of the spline, and old aluminium frames are brittle.
- Sills and reveals: vacuum before wiping. In winter, check the bottom corners of bedroom windows for condensation mould and treat it early, while it is still on the surface.
Mistakes worth avoiding
- Newspaper. Modern inks and papers are not what they were, and it leaves lint and grey marks on frames.
- Ammonia-based cleaners on tinted glass. Window film manufacturers generally advise against them, and the film is on the inside face where you are cleaning. Mild soap and water is the safe answer.
- Cleaning a whole house with one bucket of water. Once the water is grey, you are painting dirt on.
- Standing on the ledge, the sink, the balcony rail or a wobbly ladder. No pane of glass is worth it.
When to call someone in
Ground-floor windows on a single-storey house are a genuinely satisfying weekend job. Beyond that, the calculation changes: anything above ground level, anything requiring roof or balcony access, fixed windows in apartments that cannot be reached from inside, atrium glass and shopfront awnings all need equipment and training rather than enthusiasm.
Water-fed poles with purified water handle a lot of that work from the ground — the purified water dries without leaving mineral spotting, so the glass is left to air dry rather than squeegeed. It is why high-level commercial glass can be cleaned safely without anyone leaving the footpath.
For homes, window cleaning sits under our additional cleaning services. For businesses it is usually bundled into a regular schedule — monthly or quarterly for a retail shopfront, annually or half-yearly for the external glass on an apartment building’s common areas. Tell us how many panes, how high and whether there is safe ground access, and that is enough for a quote.
Questions we get asked
How often should windows be cleaned?
For most homes, twice a year is a reasonable rhythm — after pollen season and again before summer. Road-facing, coastal and construction-adjacent windows need it more often. Shopfronts are usually weekly or fortnightly, because they are judged from the footpath every day.
Can I just use dishwashing liquid?
Yes — a few drops in a bucket of cool water. The mistake is using it at washing-up strength. If the glass feels squeaky and grabs the squeegee, there is too much soap; if the blade drags and chatters, there is not enough.
Why do my windows only look streaky in the afternoon?
Because low, raking sunlight reveals film that flat daylight hides. The streaks were always there. Check your work on an angle before you pack up and you will catch them at the time.
Do you clean tracks and flyscreens too?
Ask, because it varies between providers and it is the most common gap between two quotes. Tracks, sills and screens take real time, so they should be specified rather than assumed — in an end-of-lease clean they are non-negotiable, and a finger run along a track is one of the first things checked at a final inspection.
What about windows that do not open, or are two storeys up?
Those are pole or access-equipment jobs. If a window cannot be reached safely from the ground or from inside, it needs the right equipment — not a ladder on a garden bed.
