Not all soaps are appropriate for window glass. The characteristics that make a cleaner effective on dishes or countertops — high surfactant concentration, fragrance additives, conditioning agents — often produce exactly the residue film and streaking you’re trying to avoid on glass. Here’s what actually works.

What Makes a Good Window Soap

A window cleaning soap needs to cut grease and organic film at low concentration, rinse clean without leaving residue, and be pH-neutral to avoid damaging coatings. That’s it. Fragrance, color, thickeners, and conditioning agents are all negatives on glass.

What Works for DIY Window Cleaning

A few drops of unscented, non-moisturizing dish soap — plain Dawn original is the professional benchmark — in a bucket of purified water is the most reliable DIY window cleaning solution available. Use far less than you think: one or two drops per gallon. Visible suds mean too much soap, which leaves residue.

Commercial window cleaning concentrates like Ecover or professional-grade Ettore Squeegee concentrate are better options if you’re cleaning windows regularly — they’re formulated specifically to rinse clean without film.

The Naples Water Problem

The single most important variable isn’t the soap — it’s the rinse water. Naples tap water is hard enough that it deposits visible minerals on glass as it dries, regardless of how good your cleaning solution is. For best DIY results, use distilled water for both the solution and the final rinse. For professional results, deionized water is the standard.