Streaks are usually left by the water, not by the dirt you were trying to remove. Tap water carries chlorine, nitrates, phosphates, and other metals. On a warm pane those minerals dry in place, so the glass can look washed and still look spotted once the sun hits it. Ordinary soap adds a second problem. It leaves a thin film, and the next dusty day sticks to that film.
A clear result starts with water that has already had those minerals taken out. The rinse used on exterior glass here is put through a four-stage filtration system so chlorine, nitrates, phosphates, and heavy metals are filtered out before the water ever touches the pane. The glass is brushed and rinsed with that pure water, then left to dry. There is no chemical to buff off, and there is no sticky layer waiting for the next coat of dust.
The frame is part of the same job. Dirt sits in the corners, on the sill, and in the track. If only the centre of the pane is wiped, the next rain carries that dirt back onto the glass. That is why windows and frames are cleaned together, from the ground, instead of treating the glass as a separate surface.
Screens need a decision before the visit. Unless screen cleaning is included in the package, screens need to be removed prior to the appointment or an additional charge is added. A screen left in the frame blocks the brush and holds its own dust against the glass. Deep screen cleaning can be booked when you want the mesh done at the same time, and the complete package covers interior windows, exterior windows, and the screens together.
What to do before the crew arrives
A clear path along the wall saves time and avoids missed panes. Move bins away from the glass, coil hoses, and shift light furniture that sits tight against a window. Mention a locked side gate, a dog in the yard, or a bed that should not be walked through. If a pane is cracked, say so. The brush is gentle, but a crack you already know about should not be a surprise on the day.
Interior glass is a different visit from the outside. The outside collects road film, pollen, and whatever the weather leaves. The inside collects fingerprints, cooking film, and dust from the room. Booking both makes the house look finished, because you can see through the window instead of looking at whichever side was skipped.
Upper glass, and how often to repeat the wash
Second-storey panes are the ones people delay, because a ladder feels like the only way to reach them. It is not. Those windows can be cleaned from the ground with a pole fed system that reaches up to 60 feet. The pole keeps ladders off the frames and off the siding, which is how scratches and dents get avoided, and it keeps the person doing the work on the ground.
How often the wash is worth doing depends on trees, traffic, and which way the house faces. Many homes in the GTA, Hamilton, Burlington, Ancaster, and Niagara do well with a spring wash after pollen and another wash later in the year. A house on a busy road, or under trees that drop sap, usually needs a shorter gap. The fuller explanation of that timing is in how often exterior windows need a wash.
Work in the shade when you judge the result, then check the same pane in sun. Spots that vanish in flat light and show up in sun are dried minerals, not dirt the brush missed. If a pane still has a greasy arc after it dries, that is leftover soap from an earlier wash, and a pure-water rinse is what lifts it. Do not follow the crew with a dry cloth. Wiping filtered water off with a household towel puts lint and cleaner back on the glass you just had finished.
If you want the outside of the house done without chemicals, that is the method itself, not an extra. A chemical-free wash means the pure water is the cleaner. Once the crew leaves, there is no residue for children, pets, or the garden to avoid. The practical test is simple. Look at the pane in open daylight. You should see through it, without soap rainbows and without mineral dots where the rinse dried.