When homeowners book a professional cleaning, one of the most common questions is about interior vs exterior window washing — what’s actually different between the two? The methods, tools, frequency, and even pricing can vary significantly. Here’s everything you need to know.
Interior vs Exterior Window Washing: The Core Differences
The fundamental difference between interior and exterior window washing comes down to the type of dirt being removed. Interior glass collects dust, fingerprints, pet nose prints, cooking residue, and smoke film. Exterior glass faces weather, pollen, bird droppings, hard water from sprinklers, road salt, and pollution. Each requires different cleaning solutions and techniques.
Tools and Methods: How Interior and Exterior Cleaning Differ
For interior windows, professionals typically use microfiber cloths, squeegees, and gentle cleaning solutions to avoid drips on floors, walls, and furniture. Drop cloths are placed under windows, and care is taken with window treatments and surrounding decor.
Exterior window washing requires more robust equipment — extension poles, water-fed pole systems with purified water, ladders, and sometimes lifts for multi-story homes. Professional-grade detergents are used to break down weather-baked grime that household cleaners can’t touch.

How Often Should You Schedule Each?
- Exterior windows — Twice a year minimum (spring and fall). Homes near trees, busy roads, or with sprinkler exposure may need quarterly cleanings.
- Interior windows — Once or twice a year for most homes. Households with pets, smokers, or frequent cooking may benefit from more frequent service.
Pricing: Is Interior vs Exterior Window Washing Different?
Yes, and it makes sense once you understand why. Exterior cleaning often costs slightly more because it requires more equipment, more time, and sometimes additional safety measures for hard-to-reach windows. However, most homeowners book interior and exterior together, which is the most cost-effective option — you get a thorough job at a better rate than booking each separately.
Can You Do One Without the Other?
Absolutely. Many of our Chicago-area customers book exterior-only service in between full interior + exterior visits, since exterior glass gets dirty faster. Others book interior-only after a renovation, a move, or before hosting guests. We’re flexible with whatever scheduling works for your home and budget.

Our Recommendation
For most Chicago-area homes, the best value when comparing interior vs exterior window washing is to book both at the same time twice a year — in spring and fall. This maintains clarity year-round and catches issues like hard water buildup or seal damage before they become expensive problems.
Ernest Windows serves Deerfield, Northbrook, Glenview, Buffalo Grove, Arlington Heights, and the surrounding Chicago area — seven days a week with no extra charge for weekends. Contact us today for a free estimate on interior, exterior, or full-service window washing.




