How to Clean Windows

Quick answer: Use white vinegar diluted with water or a few drops of washing-up liquid, two microfibre cloths, and work from top to bottom in the shade. Remove all liquid before it dries – that single step prevents most streaks.

You cleaned the windows, stood back, and the sun came out. Streaks everywhere. You are not doing it wrong – you are just missing one or two details that make the difference. Here is exactly what they are.

Why Do Windows Streak?

Too much soap leaves a film that dries visibly on the glass
Hard tap water deposits calcium and magnesium as it evaporates, leaving hazy white marks
Liquid left to dry on its own – the single most common cause, and the easiest to fix

What You Actually Need

You do not need specialist equipment. Most people already have everything required.

Two microfibre cloths – one damp for cleaning, one dry for buffing. This is the most important item on the list. A cheap supermarket microfibre works well; the key is using two separate cloths, not one for everything. Microfibre lifts and traps dirt rather than spreading it around, which is why it outperforms kitchen roll, cotton cloths, and old T-shirts on glass every time.

White vinegar or a small amount of washing-up liquid. Vinegar is the most popular DIY window cleaner in UK homes for good reason – it dissolves grease and mineral residue cleanly, with no film left behind. Washing-up liquid works equally well in very small amounts.

A spray bottle for applying your mix evenly without oversaturating the glass.

A squeegee is worth adding if you do not already own one. A basic rubber squeegee from Home Bargains or B&Q costs a few pounds and removes liquid in one clean stroke, making streak-free results significantly easier to achieve on larger panes.

That is genuinely the full kit for most homes.

The Best Cleaning Mix

Option 1 — White vinegar and water (most popular in UK homes)
Mix one part white vinegar to one part warm water in a spray bottle. This cuts through grease and hard water residue, evaporates cleanly, and leaves no film. The smell disappears within minutes of drying. Add a single drop of washing-up liquid if the glass is particularly dirty.

Option 2 — Washing-up liquid and water
A few drops – and we mean a few, not a squeeze – in a spray bottle of warm water. Fairy or any supermarket equivalent works fine. Too much is the most common mistake: excess soap is what causes the streaky film people spend time trying to remove.

Avoid window sprays with heavy fragrance, furniture polish, all-purpose cleaners, or anything oil-based. These leave exactly the residue you are trying to get rid of.

How to Clean Interior Windows: Step by Step

Step 1 — Start with the frame
(Zdjęcie 1: szara ścierka na ramie)
Wipe down the frame and sill with a damp cloth before touching the glass. Dust and grime dislodged from a wet frame drip straight onto clean glass and undo your work. One minute here saves you from doing the glass twice.

Step 2 — Apply your mix sparingly
(Zdjęcie 2: spray bottle)
Mist the glass lightly – damp, not dripping. Whether you are using white vinegar and water or a few drops of washing-up liquid, less is more. Too much liquid on the glass is one of the most common causes of streaks, because it takes longer to remove and is more likely to dry before you wipe it away.

Step 3 — Wipe, buff, and check
(Zdjęcie 3: niebieska ścierka na szybie)
Wipe the glass with your damp microfibre in straight lines from top to bottom – never in circles. Immediately switch to your dry cloth and buff before the liquid evaporates. Dry the edges where glass meets frame, then check at an angle in natural light. Any residue left shows up instantly this way.

The Biggest Mistakes

Cleaning in direct sunlight – the liquid evaporates before you can remove it. Always choose an overcast day or work on the shaded side first
Too much washing-up liquid – a few drops is the correct amount. More soap means more residue
Using one cloth for everything – cleaning and buffing with the same cloth moves dirt in circles
Skipping the edge dry – the glass-to-frame border holds water that streaks the pane below it
Using kitchen roll – it sheds lint on glass and leaves fibres behind

Squeegee Technique: The Upgrade Worth Learning

If you have a squeegee or are thinking about getting one, technique matters more than the tool itself.

Hold the blade at 30–45 degrees to the glass and work in overlapping strokes from top to bottom. Wipe the blade after every pass with a dry cloth – a dirty blade deposits whatever it is carrying straight back onto the glass. Overlap each stroke by 2–3 cm to avoid leaving a thin unwiped strip between passes. Finish by drying the bottom edge where water pools.

A cheap squeegee used correctly will beat an expensive one used badly every time.

How Professional Window Cleaners Do It – and What You Can Learn from It
People often ask: how do window cleaners get windows so clean? It is a fair question, and the honest answer is that the methods are not as different from the DIY approach above as you might expect, especially for interior glass.

For exterior windows, we use a water-fed pole system with purified water. The water is filtered to remove dissolved minerals completely, rinsed over the glass, and left to dry naturally without wiping. It is the safest method for working at height and consistently delivers excellent results – something our clients across Nottingham notice straight away.

Interior windows are a different story. For smaller jobs or windows with a modest number of panes, two microfibre cloths and a good cleaning mix – exactly what we described above – are genuinely all we use. The DIY method works; it is just slower.

It becomes inefficient on larger windows or when cleaning a significant number of panes in one visit. That is where squeegees come in. We use a set of Unger ErgoTec Ninja squeegees in different sizes, matched to the width of each pane. The right size squeegee on the right window is significantly faster than any cloth method, and the finish is exceptional – provided the technique is right. The one limitation worth knowing is that squeegees do not work well on angled surfaces. Skylights, conservatory roof panels, and large folded glass doors all present the same problem: water pulled downward accumulates at the bottom edge and, if you are not quick with a cloth, ends up on carpets or flooring.

Our preferred solution for most interior work in recent years has been a professional window vacuum. We use the Kärcher window vacuum, which removes dirty water from the glass in a single pass – no drips, no residue, no risk to floors or furnishings. It is faster than squeegee work on standard windows and leaves glass genuinely crystal clear. For high-level interior glass – anything up to around three metres – we use the Vikan EasyShine system: a telescopic handle with ultra-microfibre pads that cleans without chemicals and without a ladder, finishing with a dry buff for a spot-free result.

None of this is necessary for cleaning your own windows at home. But if you have ever wondered why a professional clean looks different from a DIY one, this is why: it is the combination of the right tool for the right surface, not a secret product.

Quick Checklist
Two microfibre cloths: one damp, one dry – never use the same cloth for both
White vinegar and water (1:1), or a few drops of washing-up liquid in warm water
Clean the frame before the glass
Work from top to bottom, always
Never clean in direct sunlight
Remove liquid before it dries – do not let it evaporate on its own
Wipe your squeegee blade after every pass
Dry the edges where glass meets frame
Check at an angle in natural light before you finish

Frequently Asked Questions
Why do my windows streak after cleaning?
Usually one of three causes: too much soap leaving residue, hard tap water depositing minerals as it evaporates, or liquid left to dry before being wiped away. Fix all three and the streaks stop.

What is the best homemade window cleaner?
One part white vinegar to one part warm water in a spray bottle. It dissolves grease and hard water residue, dries completely clean, and costs almost nothing. Add a single drop of washing-up liquid for heavily soiled glass.

Is vinegar safe on glass and uPVC frames?
Yes. Diluted white vinegar is safe on standard window glass and uPVC frames. The smell disappears quickly once dry.

Should I clean windows in sunlight?
No. Sunlight causes your cleaning liquid to evaporate before you can wipe it away, leaving residue on the glass. Choose a cloudy day or clean the shaded side of the house first.

Do I need distilled water?
Not always. If your tap water is very hard – you will know because your kettle scales up quickly – distilled or demineralised water makes a noticeable difference, as it dries without leaving mineral deposits. It is available cheaply in most supermarkets. For most homes, white vinegar in tap water handles the mineral issue effectively enough.