Okna Windows for Window Replacement in Maryland

Don’t spend more than you need to on replacement windows!

Call us today for a free in-home consultation (301) 658-2492

Most Window Projects Installed 2 -4 Weeks After Contract Is Signed.

 $100 off per replacement window window replacement in maryland

Before you buy Renewal By Andersen,  Thompson Creek, Windows on Washington or any other replacement windows you owe it to yourself to look at our Starmark Windows by Okna Windows & Doors.   Why spend as much as 50% more with a different replacement window contractor when you can enjoy the exceptional quality and value of Starmark Windows by Okna?

Below are some things to consider when comparing windows.  These are some features and benefits of our Starmark replacement window by Okna Windows. You can see our Okna replacement windows by clicking here.

  • Cellular composite window frame:
    • This material is 70% more insulating than wood,
    • 214% more insulating than vinyl,
    • and a whopping 1600% more insulating than aluminum.
    • Unlike wood, cellular composite is non-absorbent, impervious to rot, insect-resistant and dent-resistant.
    • Unlike vinyl, cellular composite holds its shape under the weight of glass and prolonged exposure to the sun’s heat. The attractive, paintable surface outperforms all other window frame materials.

    We Offer 4 Different Okna Replacement Window Options To Suit Your Budget & Needs.

    Click any of the links below to see a brochure about each product line.

    Okna 900 Series Starmark Brochure

    OknaSeries Okna Replacement Windows Starmark Brochure

    Okna 800 Series Enviro Star Brochure

    OknaSeries Okna Replacement Windows Starmark Brochure

    Okna 500 Series Insul Tec Brochure

    OknaSeries Okna Replacement Windows Starmark Brochure

    Okna 400 Series Precision Weld Brochure

    OknaSeries Okna Replacement Windows Starmark Brochure


Fill out the form below or call us today for $100 off per window when you buy 4 or more windows. Call us today (301) 658-2492! 

Watch A Short Video About Choosing An Energy Efficient Window From The National Fenestration Rating Council (NFRC)

Act soon and we will install your windows in three weeks!

Okna Windows Insulators Home Exteriors

At Insulators Home Exteriors we realize that the window and door buying process can be confusing, overwhelming and time consuming. We’ve been doing this for over 37 years with over 35,000 satisfied customers and wanted to share with you some things that should be considered in your buying process.

Act soon and we will install your windows before cold weather and winter arrives.

Contact Us

Please submit the information below. You will receive a prompt response. We look forward to working with you.

Read more about Okna Windows below.

  • Advanced glass coating: Windows represent a huge amount of undesired heat gain in the summer. A replacement window contractor can counter this trend by installing Starmark Windows by Okna. The advanced Heat Shield coating enables Starmark Windows to block most solar heat and harmful UV rays while still allowing most visible light through. That way, you preserve the view and natural lighting with less heat gain and fading from UV rays.


  • Innovative glass spacer: A special Heatseal Spacer guarantees a warmer home in the winter thanks to enhanced insulating abilities. In fact, the sill itself is as much as 15.3 degrees warmer than windows without the Heatseal Spacer. This feature also decreases condensation, thus improving window durability and performance.


  • U-Value: The Nationally recognized rating conducted by the National Fenestration Rating Council (NFRC) tests the entire window, including the Frame, the Spacers, and the Glazing of the window. High Performance Double Pane Windows will have U-Values or .30 or less, and Triple Pane windows will have U-Values as low as 0.15. The lower the U-Value , the better a window’s resistance to heat flow and better it’s insulating properties. Low U-Values are the single most important feature in heating dominated climates, and are also beneficial in cooling dominated climates. You can find information on your recommended U-Value for your climate from the Energy Star Website.  Difference between U-Value and R-Value?: Many consumers will confuse the U-Value and R-Value to be the same. The U-Value is used to express the insulation factor of windows. The R-Value is used to express the insulation in most other parts of the building platform (Walls, Floors, Roofs). To compare R-Value to U-Value, divide 1 by the U-Value. I.E.: R=1/U.


  • Fusion Welded Frame: The difference in having a mechanically fastened window frame vs. a Fusion Welded frame are huge. A Fusion Welded Frame provides more structurally support for the window as well as more Energy Efficiency. 

Starmark Windows by Okna Replacement Windows & Doors

  • Proper Installation: You can buy the Best window available and the most expensive, buy have it installed poorly to achieve no energy saving benefits. On the other hand you can buy the least expensive replacement window and have it installed properly and achieve energy efficiency benefits. Proper window installation must provide that the window should not support any load other than it’s own weight. There must be an airtight seal around the window. There must be an unbroken thermal insulation between the frame of the window and the wall. There must be some small allowance for movement between the window and the opening itself. All windows must be properly aligned into the rough opening. They must be square, plumb and level with shims and spacers to ensure durability and continuing high performance. Once installed you must ensure good thermal resistance and good air flow resistance around the sides of the window frame in the space between the frame and rough opening. High thermal resistance will keep heating loss to a minimum. Good Air flow resistance will prevent cold air from leaking around the sides of the window. The most common materials to achieve this is either injected foam or an insulating blanket.


  • Process after signing contract: After the signing of the contract, a window specialist will measure your windows within 3-5 business days. The Replacement window will be custom manufactured and ready for installation during the next 4-6 weeks. During this wait time you will be contacted with an installation date. Our Factory trained installers will install your replacement window according to “Window and Door Installation Standard”. After the Installers finish the installation all debris will be removed and disposed of properly. You will then have to sign a completion form, which signifies your satisfaction with the purchase and installation. Most Installations are completed in one day.


  • Retrofit vs. Complete tear out: A Retrofit is working within the existing frame and replacing the sash and the glazed unit with an entire new window. A complete tear out is where the entire opening is removed right back to the rough opening and replaced with a completely new window and frame.


  • Window Buying process: Once an appointment is set with your chosen window replacement contractor, a certified window estimator will visit the home. In the home you will be consulted by the estimator on the different selection of window styles, energy efficient packages, and installation techniques. The Estimator will walk around to every room and measure each window and check for current window deficiencies. All options will be presented and discussed in the home. The estimator will provide a full detailed written estimate to the homeowner. Special discounts and promotions will also be shared with the homeowner to help make the buying process easier for the homeowner.

Insulators Home Exteriors has been in business since 1977 and has extensive experience in the window replacement industry. We always offer the most innovative window products available on the market today. Insulators Home Exteriors is also an exclusive dealer of OKNA Replacement Windows and Doors.

Different styles and features of windows: There are many options in terms of window styles and options for homeowners to choose from. Decisions need to be made on style of window, color of window on exterior and interior frame, glass packages available , and grid options.

Window Styles:

  • Double Hung
  • 2 Piece Slider
  • 3 Piece Slider
  • Casement
  • Picture
  • Bay and Bow window

Contact us today at (301) 658-2492 and learn firsthand why Okna Windows has been dubbed the Best Replacement Windows in America.


See our other replacement window pages.

Click here for more window pages – OKNA 500 Series Slider Windows

Click here for more window pages – Okna 500 Series Double Hung Replacement Windows

Click here for more window pages – Replacement Windows In Maryland Are Worth The Investment!

Click here for more window pages – Okna 800 Series Replacement Window

Click here for more window pages – Okna Replacement Windows & Doors – Starmark Windows

Click here for more window pages – Various Replacement Window Maryland Renovation Projects

Click here for more window pages – Double Hung Windows

Click here for more window pages – Bay Window