Why Do My Windows Streak Even Straight After Cleaning?

The Direct Answer

Streaks after a window clean usually mean something was left on the glass to dry: a trace of detergent, hard water minerals, or dirty water dragged back across the pane by a cloth or squeegee. Pure water cleaning, which we use on every window in Rayleigh, avoids the problem at the source. The water has had its minerals stripped out, so there is nothing left behind to dry into a mark, and the glass is rinsed rather than wiped.

What actually causes streaks

• Hard water. Essex water carries a lot of dissolved minerals. A normal hose or tap fill dries into a white haze on dark glass, especially conservatory roofs and black-framed windows.
• Leftover detergent. Washing-up liquid or a shop-bought glass cleaner leaves a thin film that catches the light once it dries.
• A dirty cloth or squeegee blade. Dragging the same grime back across clean glass just relocates it.
• Drying in direct sun. Fast drying leaves whatever was in the water concentrated on the surface before it can run off.

How pure water cleaning avoids it

Water is run through a resin filter that removes the dissolved minerals, so it comes out at close to zero parts per million. Brushed onto the glass off a pole and left to run off, it dries completely clear because there is nothing dissolved in it left to dry into a mark. Frames and sills get the same water, which is why they come up clean too, not just the glass.

Why this matters more in Rayleigh than it sounds

Homes along the busier roads pick up traffic film fast, and a streaky clean shows that film straight back up within days. A proper pure water clean, frames and sills included, holds its finish for the full four to eight weeks between visits rather than looking patchy by the following week.

FAQ: Can I get streaks even with pure water?

Only if the glass is touched afterwards with a dry cloth, which reintroduces dust and smearing. Left to air dry, pure water does not streak.

FAQ: Does this work on conservatory roofs?

Yes, and it matters more there because dark polycarbonate shows mineral haze the worst of any surface in the garden.

FAQ: What does window cleaning cost in Rayleigh?

From £18 a clean on a four-weekly cycle for a standard house. Full prices and what is included are on the window cleaning page.

No deposit. Call 07467 214446 or message us on WhatsApp for a price.