Est. 1957
Window & Door Replacement
in Lake County, IL
Serving Libertyville, Grayslake, Vernon Hills, Lake Zurich, and Hawthorn Woods
Expert guidance for your home since 1957.
Get a detailed assessment and honest recommendations for your project.
- Family-owned since 1957
- Owner-involved on every project
- Written estimates — clear scope and expectations
- Serving Lake County & Chicago's Western Suburbs
What We Do
Window and door replacement focused on installation quality, long-term performance, and respect for your home — serving Lake County, IL and Chicago's western suburbs since 1957.
Window Replacement
Insert and full-frame replacement for homes of any age. Double-hung, casement, sliding, and specialty configurations. Low-E insulated glass standard.
Window Replacement in Lake County →Entry & Patio Doors
Complete door system installation — frame, threshold, hardware, and weatherstripping. Fiberglass, steel, and wood. Sliding and French patio door replacement.
Door Replacement in Lake County →HOA & Contractor Support
Multi-unit programs, product specification compliance, and phased scheduling for HOA boards, property managers, and general contractors.
Learn more →Recent Projects
See the finish quality and clean install standards we hold on every job.
Arlington Heights Window Replacement
Professional window installation and replacement
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After
Before
About K Windows
Kornesczuk Windows is a family-run window and door replacement company serving homeowners and property managers across Lake County, IL and the western suburbs of Chicago. from grayslake to wheaton, three generations of experience and an honest estimate process with no pressure to sign on the spot.
We show up when we say we will, complete the work correctly, and stand behind it.
Our Story →
Start with an Honest Estimate
We assess the actual conditions and provide a written proposal with clear scope and expectations. No pressure, no manufactured urgency.