Expert window replacement and door installation. Done right, on schedule, by our own licensed crew. No subcontractors. No surprises. Just results your neighbors will notice.
Trusted Brands We Install
Windows 4U was founded by brothers Alex and Leon Elbert, two Bay Area contractors with 20+ combined years installing windows and doors across the East Bay. They started Windows 4U because homeowners kept asking for the same thing: someone reliable who communicates clearly and does the job right the first time.
From retrofit replacements to full-frame installs and new construction, Alex and Leon lead every project personally. No subcontractors, no call centers. Just honest work from local professionals who stand behind every install.
From single-window retrofits to full-home door upgrades. We handle every aspect of installation with precision, clean workmanship, and materials built to last.
Casement, double-hung, bay & bow, picture, awning, slider, and more. Vinyl, fiberglass, aluminum, and wood options. Retrofit or full-frame installs.
View Window Services →
Upgrade your curb appeal and home security. We install fiberglass, steel, and wood entry doors with a wide selection of styles, finishes, and glass inserts.
View Entry Doors →
Create a seamless indoor-outdoor connection. Premium vinyl, aluminum, and fiberglass sliding glass door and patio door systems built for the Bay Area climate.
View Patio Doors →A sample of completed window and door installations across Walnut Creek, Concord, Lafayette, and the East Bay.
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New windows change how a home looks, feels, and performs, better insulation, cleaner lines, and curb appeal that lasts.
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We make it easy however works best for you. Prefer to stay home? Send us a few photos and rough measurements and we'll reply with a detailed written quote — usually within 48 hours, though we try to get back to you as fast as we can. Rather have us come take a look? We're happy to visit and measure in person — no pressure, no obligation.
We're not a big-box retailer or a call-center company. We're licensed local contractors who answer the phone, show up on time, and stand behind every installation we do.
CA Contractor Lic. #1097508. Fully bonded and insured, you're protected on every job, no exceptions.
No subcontractors. Alex and Leon's own crew handles every installation, consistent quality, every single project.
You'll always reach us directly by phone, SMS, or WhatsApp. No voicemail trees or call centers.
We stand behind our work with a 4-year installation warranty, plus lifetime manufacturer product warranty on most products.
We protect your home during installation and leave your space spotless. Your floors, furniture, and landscaping are safe with us.
No surprise charges, no bait-and-switch. You receive a detailed written quote before any work begins, and that's the price you pay.
From your first inquiry to the final walkthrough, here's exactly what to expect when you work with Windows 4U.
Contact us online, by phone, SMS, or WhatsApp. We offer in-home and remote estimate options to fit your schedule.
We take precise measurements and walk you through product options, styles, materials, and energy performance ratings.
Our in-house crew installs your windows or doors efficiently, cleanly, and to the highest industry standards.
We review every installation with you personally and don't leave until you're 100% satisfied with the results.
We specialize exclusively in full window and door replacement. We do not offer:
Not sure if you need replacement or something else? Call us, we'll give you an honest answer, even if it means we're not the right fit.
We work alongside general contractors, builders, and property managers on large-scale projects. Not just individual homeowners.
Installation is not required. We source from the same manufacturers we use on our own jobs — Milgard, Anlin, ProVia, Marvin, and more.
Discuss Your Project →5-star rated on Yelp and Google by homeowners across Walnut Creek, Concord, Pleasant Hill, and the East Bay.
"Alex and Leon replaced all the windows in our Walnut Creek home. Professional, on-time, and the work is absolutely beautiful. No mess left behind and the price was very fair."
"Had them install a new sliding glass door and two casement windows. The process was smooth from start to finish. They communicate quickly and the installation quality is top-notch."
"Got three quotes, Windows 4U wasn't the cheapest, but definitely the most professional and responsive. Worth every dollar. My new entry door looks incredible."
Everything you need to know about window replacement and door installation in the Bay Area.
Serving the Bay Area Including
San Francisco & San Jose available for select projects
