Exterior Window Cleaning in Fresno: Why Fall Light Makes Every Streak Show

Every September we get calls from homeowners who swear their windows were fine a few weeks ago and now suddenly look filthy. Nothing changed about the glass. What changed is the sun. Exterior window cleaning in Fresno is worth thinking about differently once fall sets in, because the light itself starts working against you.

Why fall sun is harder on windows than summer sun

In summer the sun sits high overhead through most of the day, so it strikes your windows more or less straight on and a lot of dust and haze just does not catch the light. By September and October the sun drops lower in the sky, especially in the afternoon, and it comes in at more of a side angle. That low, raking light hits the glass almost edge on, and it lights up every streak, water spot and cobweb like a spotlight. Homes in Fresno and Clovis with west or south facing windows notice it the most, since that is where the afternoon sun lands directly on the glass.

The grime was there all along

This is the part that catches people off guard. The dust film and hard water spots that built up over the summer did not disappear when the heat broke, they were just harder to see under the high midday sun. A window that looked reasonably clean in July can look neglected in September without a speck of new dirt landing on it, purely because the light is doing a better job of exposing what is already there.

Getting ahead of it before the sun drops even lower

A proper exterior window cleaning starts with a soft applicator to loosen dust and mineral film, followed by a squeegee pass so the water and grime come off before they can dry on the glass. Purified water helps here too, since it rinses clean without leaving the spotty residue that tap water does. Fall mornings and evenings in the Central Valley are mild enough that the solution has plenty of time to work, which actually makes this an easier season to get streak free results than the middle of summer. Get it done now and your windows will hold that clarity right through the lower light of late fall, before winter rain starts kicking dust back onto the glass.

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