How to Clean Double Pane Windows

Double-pane windows require a slightly different cleaning approach than single-pane windows. The key is knowing what you can clean yourself and what requires professional help. Here's everything you need to know.

What You Can and Cannot Clean on Double-Pane Windows

• Can clean yourself: The exterior glass surface, the interior glass surface, the frame, and the sill
• Cannot clean yourself: Dirt, fog, or condensation between the two panes — this is inside the sealed unit and requires IGU replacement

If your double-pane window looks foggy or has streaks that don't wipe off, the seal has failed and the glass unit needs replacement — no amount of cleaning will fix it.

What You'll Need

• Window squeegee
• Microfiber cloth or scrubber
• Cleaning solution (dish soap and water, or white vinegar and water)
• Extension pole for high windows

• Window Squeegee Cleaner with Extension Pole and Microfiber Scrubber — 12" squeegee and 11" microfiber scrubber combo; extension pole reaches high double-pane windows without a ladder

Step 1: Choose the Right Day

Clean windows on a cloudy day or in the shade. Direct sunlight dries the cleaning solution before you can squeegee it off, leaving streaks. Early morning or late afternoon on a cloudy day is ideal.

Step 2: Prepare the Cleaning Solution

Mix a few drops of dish soap in a bucket of warm water, or use a 50/50 solution of white vinegar and water. Avoid ammonia-based cleaners on double-pane windows — ammonia can damage the low-E coating on some glass types.

Step 3: Wet the Glass with the Scrubber

Dip the microfiber scrubber in the cleaning solution and wet the entire glass surface. Scrub in circular motions to loosen dirt and grime. Pay extra attention to the edges and corners where dirt accumulates.

Step 4: Squeegee in an S-Pattern

Starting at the top corner, pull the squeegee across the glass in overlapping horizontal strokes. Wipe the squeegee blade with a clean cloth after each stroke. Work from top to bottom. The S-pattern ensures no area is missed.

Step 5: Wipe the Edges

Use a dry microfiber cloth to wipe any water from the edges of the glass and the frame. Water left at the edges causes streaks and can damage the frame seal over time.

Step 6: Clean the Frame and Sill

Wipe the frame and sill with a damp cloth and dry thoroughly. See our guides on cleaning window frames and window sills for detailed instructions.

Dealing with Hard Water Spots

Hard water spots (white mineral deposits) on double-pane glass respond well to undiluted white vinegar. Apply, let sit for 5 minutes, then scrub and squeegee off. For severe deposits, a commercial lime and calcium remover works well.

What to Do About Foggy Double-Pane Windows

If the fog is between the panes and doesn't wipe off, the IGU seal has failed. The glass unit needs replacement by a glazier. No cleaning product or method can fix a failed seal.