How to clean windows streak free

To clean windows streak free, wash the glass with warm water and only a tiny drop of washing up liquid, take the water off with a clean squeegee, and finish the edges with a dry microfibre cloth. Do it out of direct sun, because glass that dries too fast is what leaves most streaks behind.

That is the short answer. Below is why streaks happen, a step by step method you can use at home, and how window cleaners get the outside glass clear without any product at all.

Why windows streak

A streak is whatever was in the water, or on the cloth, left behind on the glass after the water has gone. The usual causes are:

• Too much product. Washing up liquid and glass sprays leave a film if you use too much or do not take it all off.
• Minerals in tap water. Tap water carries dissolved minerals, and when a drop dries on its own those minerals stay on the glass as a spot or a smear.
• Drying too fast. In warm sun or wind the water dries before you can wipe it, so the dirt dries with it.
• Dirty or fluffy cloths. A cloth that has been used on the frames, or a tea towel that sheds, puts dirt and fibres straight back on.
• A worn squeegee blade. A nicked or hardened rubber leaves a thin line of water every time you pull it across.

What you need

• A bucket of warm water with a very small drop of washing up liquid
• A sponge or a strip washer to wet the glass
• A squeegee with a clean, sharp rubber blade
• Two or three dry microfibre cloths, kept only for glass
• A separate cloth for the frames and sills

Step by step method

1. Pick your moment. A dry, overcast day or a window that is in shade is best. Avoid glass that is warm from the sun.
2. Clean the frames and sills first. If you do them last, the dirt you knock off lands on the clean glass.
3. Wet the whole pane with the sponge or strip washer. Rub harder on bird mess and the bottom corners, where dirt builds up.
4. Squeegee from the top. Start with a strip along the top edge, then pull down or work across in an S shape, overlapping each stroke a little.
5. Wipe the blade after every stroke with a cloth so you are not dragging water back across the glass.
6. Finish the edges. Run a dry microfibre cloth round the edge of the glass where the squeegee cannot reach, then catch any drips on the sill.
7. Check from an angle. Streaks show up best when you look along the glass rather than straight through it. Buff any marks with a dry cloth.

If you only have a cloth and no squeegee, use one damp microfibre to clean and a second dry one to buff straight after, working on a small area at a time so nothing dries on its own.

Outside windows and staying safe

Downstairs windows are easy to do yourself. Upstairs is where people get hurt. If you use a ladder, set it on firm, level ground, keep three points of contact and keep your belt buckle between the stiles, which is the guidance from the Health and Safety Executive. Do not lean out to reach the far corner. Move the ladder instead.

Never rest a ladder on a gutter, a conservatory roof or plastic window frames. They are not built to take the weight. If you cannot reach a window comfortably and safely, it is a job for a pole from the ground or for a professional.

How pure water leaves no streaks

Most window cleaners now use a water-fed pole. The water is filtered to take the minerals out of it, so when it dries there is nothing left to leave a mark. No soap is used at all, which means there is no film on the glass for fresh dirt to stick to.

That is why pole-cleaned windows are left wet. It is not a missed step. Pure water dries spot free on its own, and the glass usually stays clean for longer than it would after soap and a squeegee. The frames and sills are scrubbed with the same brush on the way, which is something a quick wipe at home often misses.

When to call a window cleaner

Doing the inside and the downstairs yourself is fine. It is worth handing the rest over when:

• The windows are upstairs, over a conservatory or above steps and slopes
• You live near the sea and salt film keeps coming back
• The frames have gone green or grey and need a proper scrub
• You would rather not be up a ladder at all

Window cleaning in Torbay and Exeter

AbraClean has cleaned windows across Torbay and Devon since 2001 using a water-fed pole from the ground, with glass, frames and sills done on every visit. See our window cleaning service, or find your town, including Paignton, Torquay and Exeter. Call or text Mark on 07901 563000 for a free quote.