Streak-free windows: how the professionals do it

The right tools: applicator, squeegee and microfibre

Professional window cleaners work with a window applicator (washer sleeve), a squeegee with a sharp, clean rubber blade and lint-free microfibre cloths. Use lukewarm water with a glazing-safe cleaner at a sparing dose. Extra detergent does not make the glass cleaner; it leaves a greasy surfactant film.

Clear the windowsill first and put a towel underneath. Separate cloths are used for frame cleaning and for the glass so that no soot, pollen or road grime gets from the frame onto the pane.

• Window applicator and squeegee with an intact rubber blade
• Lint-free microfibre cloths (washed without fabric softener)
• Lukewarm water with sparingly dosed cleaner
• Separate cloths for frames, rebates and glass panes

Do not clean in direct sun or frost

Direct sunlight heats the pane and dries the wash water before it can be squeegeed off. Stubborn smears, streaks and limescale rings remain. Clean on an overcast day if possible, or when that side of the building is in the shade.

Hard frost is also unhelpful because water can freeze on the cold glass and rubber squeegee blades turn stiff. If you clean your windows thoroughly twice a year, spring (to remove pollen) and autumn before winter sets in are the best times.

Manufacturer guidance: Kärcher

Frame cleaning first, then glass in strips or S-strokes

Interior and exterior window frames, rebates, hardware and the windowsill are cleaned first. If you started with the glass, dirty water would run over the clean pane again while you wiped the frame.

Then the pane is scrubbed thoroughly with the wet applicator and squeegeed in overlapping vertical strips from top to bottom or using a continuous S-stroke technique. After each stroke, wipe the rubber blade with a cloth. Finally, detail the glass edges along the rubber seal with a dry microfibre cloth.

If smears or a grey haze remain, the cause is usually overdosed cleaner, a nicked rubber blade or fabric-softener residue in the cloth. Wiping with clean or demineralised water then helps more than rubbing dry.

Frames, rebates, drainage slots and seals

Dust, soot, insects and leaves collect in the rebates – the inner grooves between frame and sash. A damp cloth and a narrow brush loosen the grime. Keeping the bottom drainage slots clear allows rainwater to run off freely to the outside.

Rubber seals are cleaned gently with water only, as harsh solvents make them brittle. uPVC frames cannot take abrasive scouring cream, and wooden frames should not be soaked, only wiped damp.

When a professional window cleaner is worth it

With many or floor-to-ceiling glass surfaces, conservatories, glass roofs, roof windows, shopfronts or windows that are hard to reach from outside, professional window cleaning saves time and avoids ladder hazards. For difficult exterior glazing, telescopic poles or pure-water (reverse-osmosis / demineralised water) systems are often used – and after building work, specialist post-renovation cleaning removes paint, plaster and mortar splashes without scratching the glass.

TF Clean provides window and glass cleaning including frames, rebates and sills for private homes, offices and commercial premises in Riesa and the surrounding area, as a one-off or on a fixed schedule. For a quote, the number of windows, the floor level and a few photos are enough.