A quick spray-and-wipe works fine for a small apartment window. But on larger properties — especially ones with floor-to-ceiling glass, multiple stories, or hard-to-reach exterior panes — DIY window cleaning runs into problems that store-bought products can't solve.

Why Streaks Happen

Streaks usually come down to one of three things: hard water mineral deposits, using the wrong tool for the glass size, or cleaning in direct sunlight (which dries the solution too fast, leaving residue behind). On large windows, all three problems compound — more surface area means more room for streaking, and more time spent trying to fix it.

The Access Problem

Beyond streaking, height and access are where DIY really falls short. Second-story windows, skylights, and glass facades often require ladders, extension tools, or safety equipment most homeowners don't have — and shouldn't need to risk using.

What Professional Cleaning Solves

At CorePro, we use the right tools for the surface and the access point — squeegee techniques that avoid streaking on large panes, and safe methods for windows that are difficult or unsafe to reach from the ground. The result isn't just cleaner glass; it's a safer, more efficient process than most homeowners can replicate on their own.

When to Call a Professional

If your windows are hard to reach, if streaking keeps coming back no matter what product you try, or if you're maintaining a property with a lot of glass, it's usually more efficient — and safer — to bring in a team built for it.

Quick Tip for Between Cleanings

For interior windows you can reach safely, a microfiber cloth and a mix of water with a small amount of vinegar works well for spot maintenance between professional cleanings. Save the ladder and the exterior glass for the professionals.