Window Installation & Replacement
OKNA Window Installation & Replacement in PA, MD & DE
TC Backer Construction installs and replaces energy-efficient OKNA® windows for homeowners across Pennsylvania, northern Maryland, and Delaware. We install premium OKNA windows — among the most airtight, best-built vinyl windows on the market — custom-made for a precise fit and backed by free written estimates and financing.
Why OKNA
Why we install OKNA windows
We install OKNA, a premium vinyl window manufacturer founded in 1994 in Bucks County, Pennsylvania. It’s a product we know inside and out, install to spec, and stand behind. OKNA windows are custom-made to fit your openings exactly and engineered to meet or exceed ENERGY STAR®, AAMA, and NFRC certifications.
That airtight construction, paired with HeatSeal® warm-edge spacers and ClimaGuard® Low-E glass, is why OKNA windows stay comfortable and quiet through PA, MD, and DE seasons — without dimming your view.
The OKNA Enviro-Star double-hung window’s air-infiltration rating — among the most airtight in the industry. Most competing vinyl windows rate 0.2–0.3 CFM, so less of the air you’ve paid to heat or cool leaks out.
Product lines
OKNA window lines we offer
OKNA builds tiered product lines so you can match performance and budget. We help you choose the right one for your home and goals.
Insul-Tec 500
A traditional look with all the benefits you expect from quality vinyl windows — strong energy efficiency, a maintenance-free multi-chamber frame, and a range of options to enhance your home. A great-value entry into OKNA quality.
Enviro-Star 800
OKNA’s flagship replacement window. Combines an old-world, elegant look with top-tier energy performance, a full 3¼" welded mainframe for superior strength, and the industry-leading 0.01 CFM airtight rating on the double-hung.
Starmark
Another OKNA line offering custom-made fit and dependable vinyl performance, giving homeowners additional options to match style, performance, and budget.
Window styles
Window types we install
Whatever the opening, there’s an OKNA style for it. We install the full range of residential window types:
Double-hung
The most popular style — both sashes move and tilt in for easy cleaning. Versatile and timeless for nearly any home.
Casement
Hinged on the side and cranked open, casements seal tightly when closed for excellent airtightness and unobstructed views.
Sliding
Sashes glide horizontally — a clean, easy-to-operate choice for wider openings and contemporary looks.
Bay & bow
Projecting window groupings that add space, light, and architectural character to a room and the home’s exterior.
Picture & specialty
Fixed picture windows for maximum light and view, plus custom shapes to fit unique openings.
Patio doors
OKNA sliding patio doors that match the energy performance and quality of the window line.
Why it matters
Signs it’s time to replace your windows
Old windows quietly cost you money and comfort. These are the signs it’s time to consider replacement:
Drafts & high energy bills. If you feel air near closed windows or your bills keep climbing, your windows are leaking conditioned air.
Condensation between panes. Fog or moisture inside the glass means the seal has failed and the window is no longer insulating.
Hard to open, close, or lock. Sticking, painted-shut, or warped sashes are both a hassle and a security concern.
Outside noise. If you hear too much of the street, your windows aren’t sealing or insulating well.
Rot, decay, or water damage. Soft frames or sills point to moisture intrusion that gets worse over time.
Fading furnishings. Without modern Low-E glass, UV light fades floors, furniture, and fabrics.
How it works
Our window process
Free consultation & measure
We assess your current windows, talk through your comfort and style goals, and take precise measurements — every OKNA window is custom-made to fit.
Line & style selection
We help you choose the OKNA line (Insul-Tec, Enviro-Star, or Starmark), window styles, glass options, and colors to fit your home and budget.
Custom manufacturing
Your windows are built to your exact openings, so they fit right the first time — which means a cleaner, faster install.
Professional installation
Our fully insured crew removes the old windows, prepares the openings, and installs and seals your OKNA windows for an airtight, weather-tight result.
Cleanup & walkthrough
We clean up completely and walk every window with you to confirm smooth operation and a finished look you love.
Why choose TC Backer
Window installation done right
A premium window only performs if it’s installed correctly. As a family-owned exterior remodeling contractor serving PA, MD, and DE since 2008, we install OKNA to the standard it’s built to.
Cost & estimates
What window replacement costs
Window cost depends on how many windows you’re replacing, the OKNA line and styles you choose, the glass and color options, and the condition of the existing openings. Rather than quote a number that won’t fit your home, we give you a free written estimate for exactly what yours needs.
We also offer financing, so you can upgrade to more comfortable, efficient windows now and pay over time. Ask about current options when you schedule your estimate.
Common questions
Window FAQs
What window brand do you install?
We install OKNA windows. OKNA is a premium vinyl window manufacturer founded in 1994 in Bucks County, Pennsylvania, known for exceptionally airtight, energy-efficient, custom-made windows — a product we know thoroughly and install to the manufacturer’s standard.
What makes OKNA windows energy efficient?
OKNA windows combine an airtight welded vinyl frame, HeatSeal® warm-edge spacers, and ClimaGuard® Low-E glass. The Enviro-Star double-hung carries an air-infiltration rating of 0.01 CFM — among the tightest in the industry, versus 0.2–0.3 CFM for many competitors — so less heated or cooled air escapes. They meet or exceed ENERGY STAR, AAMA, and NFRC standards.
Which OKNA line is right for me?
It depends on your goals and budget. The Insul-Tec 500 is a strong-value traditional option; the Enviro-Star 800 is OKNA’s premier line with the highest performance and an old-world look; and Starmark offers another custom-made option. We walk you through the differences during a free consultation.
How do I know if I need new windows?
Common signs include drafts near closed windows, rising energy bills, condensation or fog between the panes, sashes that stick or won’t lock, excessive outside noise, and rotting frames or sills. If you notice any of these, a free inspection will tell you whether replacement makes sense.
What window styles do you offer?
We install the full range of OKNA residential styles: double-hung, casement, sliding, bay and bow, picture and specialty-shape windows, and sliding patio doors — in a variety of colors and glass options.
Do you offer financing for windows?
Yes. We offer financing so you can upgrade to efficient OKNA windows now and pay over time. Ask about current options when you schedule your free written estimate.
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Windows & related services
Get a Free Window Estimate
Upgrade to airtight, energy-efficient OKNA® windows installed by a family-owned contractor serving PA, MD & DE since 2008.
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