Why glass streaks
A streak is a thin line of residue. It can be cleaning product that was not fully removed, dirt spread around by a dirty cloth, lint from a paper towel, or minerals left behind as tap water dries. Glass doors show it more than windows because they are at eye level, they catch low sunlight, and they collect hand marks in the same few places every day.
So the goal is not more cleaner. It is a light solution, removed completely, before it has time to dry on its own.
What you need
- A bucket of lukewarm water with a few drops of dish soap (or a spray bottle of half white vinegar and half water)
- A squeegee with a clean, sharp rubber blade, sized to your glass
- A sponge, soft scrubber or strip washer to apply the solution
- Two or three clean, dry microfibre cloths
- A soft brush or vacuum attachment for the frame and track
Never mix bleach with vinegar or ammonia, and do not use a vinegar solution in the same bucket as an ammonia-based glass cleaner or anything containing bleach. Bleach and acids release chlorine gas, and bleach and ammonia release chloramine gas. Do not let vinegar drip onto natural stone such as a marble or granite threshold or floor, because acid etches it. Lay a towel down first. If the glass has tint film or a special coating, test on a corner first and follow the maker's care instructions.
Step by step
- Pick the right time. Clean when the glass is in shade. In direct sun, the solution dries before you can remove it, which is the most common cause of streaks.
- Dust the frame and track first. Brush or vacuum the frame, handle area and the bottom track of a sliding door. Otherwise the grit ends up in your wash water and on the glass.
- Wet the glass. Apply the solution with a sponge or strip washer. Use enough to loosen the dirt, not so much that it runs everywhere. Scrub a little harder on handprints and nose marks.
- Dry the squeegee edge. Wipe a strip about 3 cm wide down one side of the glass with a dry cloth. This gives the squeegee a dry starting point.
- Squeegee top to bottom. Start at the top corner on the dry strip, press lightly and pull straight down, or move across the glass in a smooth S-shape. Overlap each stroke slightly.
- Wipe the blade after every stroke. A clean, dry blade is what leaves the glass clear. A dirty blade draws a line.
- Detail the edges. Run a dry microfibre cloth around the edges where the glass meets the frame to pick up the last drips.
- Do both sides. Clean the inside and outside separately. If a streak remains, you will know which side it is on.
- Final buff. A quick pass with a dry microfibre cloth removes any small smudges.
Common mistakes
- Using too much glass cleaner. More product means more residue to remove.
- Cleaning in direct sunlight. The glass dries before you finish.
- Using paper towels or old cotton rags. They leave lint and push dirt around.
- Using a worn squeegee blade. A nicked or rounded blade leaves a line every stroke. Blades are cheap to replace.
- Wiping in circles. It spreads dirt and leaves swirl marks you only see in the light.
- Forgetting the track. A gritty sliding-door track sends dust straight back onto the glass, and makes the door harder to open.
What professionals use, and why
Window cleaners rarely reach for spray glass cleaner. The common kit is a strip washer (a fabric sleeve on a T-bar) to apply the solution, a squeegee to remove it in one clean pass, and a bucket of water with a small amount of soap. The soap is there to make the water slide off the glass smoothly so the squeegee leaves nothing behind. A squeegee removes the water instead of spreading it, which is why it beats a cloth on large glass.
For stuck-on paint, tape or sticker residue, professionals sometimes use a scraper, but with care. Some glass manufacturers advise against scraping tempered glass, which most glass doors are, because it can scratch. If you are not sure what kind of glass you have or what the maker allows, use a dedicated adhesive remover and a soft cloth instead.
Storefront and office glass doors
Commercial glass doors face the same problem, multiplied by every person who walks through them.
- Focus on the push zone. Most marks land in a band around handle height, and down low where children and pets touch. Wiping that band daily keeps the door looking clean between full washes.
- Clean the hardware too. Push bars, pull handles and the frame around them get touched constantly.
- In winter, rinse before you wash. Salt spray and slush on the outside of the door scratch the glass if you scrub them dry. Rinse first, then wash.
- Plan around foot traffic. Clean doors before opening or after closing, so the glass has time to dry and nobody walks into a wet floor.
- Mind the threshold. Many entrances have stone or tile thresholds that do not like vinegar or puddles. Wring out your tools and use a dry cloth at the bottom edge.
If the simple method does not work
Cloudy haze after cleaning is usually leftover product. Wash again with plain water only, squeegee and buff. It often clears straight away.
White spots or rings that do not wipe off are often hard water minerals. Apply a half-vinegar, half-water solution, let it sit for a few minutes, then wash and squeegee as usual. Our guide to removing hard water stains covers stubborn mineral buildup in more detail.
Greasy fingerprints that smear need a little more soap in the water, or a second pass, before the squeegee.
Fog or condensation between the two panes of a double-glazed door cannot be cleaned. It means the seal between the panes has failed. That is a glazing repair or replacement, not a cleaning job.
Marks that never change may be scratches or etching in the glass itself. Run a fingernail gently over the mark. If it catches, it is damage rather than dirt, and more cleaning will not help.
Frequently asked questions
How do you clean glass doors without streaks?
Clean in the shade, dust the frame and track first, then wash the glass with lukewarm water and a few drops of dish soap. Remove the water with a clean squeegee from top to bottom, wiping the blade after every stroke, then dry the edges with a microfibre cloth. Using less product and removing it completely is what prevents streaks.
Why does my glass door still streak after cleaning?
Usually because too much product was used, the glass dried in the sun before it was wiped off, or the cloth or squeegee blade was dirty or worn. Wash again with plain water, squeegee with a clean blade, and buff with a dry microfibre cloth.
Is vinegar good for cleaning glass doors?
A half vinegar, half water solution works well, especially on hard water spots. Never mix it with bleach, and do not let it drip onto natural stone such as a marble or granite threshold, because acid etches stone.
Should I use paper towels on glass?
It is better not to. Paper towels leave lint and tend to push dirt around. A squeegee and clean microfibre cloths give a clearer result.
How often should storefront glass doors be cleaned?
It depends on foot traffic. Many busy storefronts wipe the handle-height push zone daily and give the whole door a full wash on a regular schedule, with extra attention in winter when salt spray builds up.
Why is there fog between the panes of my glass door?
Fog or condensation between the two panes of a double-glazed door means the seal has failed. It cannot be cleaned from either side and needs a glazing repair or replacement.
If it is storefront or office glass you are looking after, you can find out more on our commercial window cleaning page, and get more practical tips like this through our free cleaning tips sign-up.