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In this article, we will introduce some modern sash window replacement options and compare them to keeping the original windows and upgrading them with modern materials.
We will start with modern windows that incorporate the latest glazing and insulation technological innovations.
What is modern in new sash windows?
Modern sash windows, as the name suggests, incorporate new man-made materials, glazing technologies and modern production methods that build on the past hundreds of years of sash windows’ manufacturing heritage.
As in the past, float glass production technology revolutionized the industry and sash windows design in general, the latest glazing theologies do quite the opposite to sash windows.
New insulated glazing technologies help to save the heritage design of period wooden windows.
Let’s dig into what modern sash windows are in terms of design, materials and energy/ acoustic performance.
Materials – Modern frames
Window frames are an essential part of the windows. The window frame’s quality will determine how long the window lasts.
Modern windows are made with traditional materials such as wood or low-maintenance vinyl or composite.
Here is the full list of materials which are used in modern frames:
- Wood: This is the most commonly used material for frames as it has a high aesthetic appeal and is relatively inexpensive
- Vinyl/ PVC: Vinyl is mainly popular because of their low cost and easy maintenance. In addition, they require minimal or no paint job and do not rot or warp easily
- Aluminium clad: Aluminum-clad is popular choice because they can withstand harsh weather conditions and are highly energy-efficient
- Composite: Composite frames combine the strength and durability of wood with the low-maintenance properties of vinyl
While wooden sash windows are a perennial favourite among homeowners, newer materials like acetylated timber and uPVC are gaining in popularity due to their durability or cost.
Design – new window design developments
Surprisingly, modern sash windows look not too different from their predecessors; however, at the turn of the 21st century, we are faced with a wide range of modern options for our windows:
- Double hung
- Oriel
- Centre pivot
- Awning/hopper
Though sash windows today look strikingly similar to those from years ago, a closer inspection will reveal some differences, like that there is only one glass unit per sash, and fake glazing bars have been placed on top.
A pulley, cords and weight system traditionally lifted sash windows, but some newer models use springs / spiral balance instead. Spring balance is used in modern sash windows because they require less space inside the window frame and are more affordable to produce.
Modern timber
With the rapid advancement of technology over the past few years, many new timber treatments have become available to help protect and preserve the wood.
One such process is known as acetylation, which is used to strengthen softwood species like pine and fir. This treatment works by infusing the wood with acetylene gas in a high-pressure chamber, adding chemical bonds to its structure and increasing its resistance to moisture and rot.
In addition, acetylated wood does not respond negatively to changes in humidity or temperature, making it an ideal material for applications where extreme conditions may be present such as windows.
With its durability and weather resistance, this advanced timber treatment has opened up a world of new possibilities for wood in various industries, including the manufacturing of modern sash windows.
Glazing tech
One of the most innovative areas in the windows industry is glazing. The introduction of insulated two panes glazing in the 1970s changed construction standards and revolutionized the industry.
Glazing is what sets the modern window apart from those created several decades ago.
Newer glazing technologies like low-emissivity coatings, warm edge spacers and gas-filled or vacuum-insulated double-glazed units are more energy efficient than a single pane of glass used in original sash windows. Double glazing for sash windows is beneficial because it provides superior insulation, enhances energy efficiency, reduces outside noise, and helps maintain a comfortable indoor environment.
For modern sash windows, manufacturers are also experimenting with various types of glass, including laminated, toughened, and self-cleaning varieties.
Seals
Modern sash windows are ready draught-prodded, unlike timber windows from previous eras. Modern rubber seals around the sashes and frames help to keep out moisture, cold air, and noise while also providing a tight seal.
High-quality modern windows and cheap stuff
The invention of cutting-edge manufacturing machinery and materials resulted in a dichotomy for customers: they could purchase high-quality windows with previously unattainable energy efficiency or cheaper alternatives that anyone could afford.
Cheap uPVC windows or cheap new timber windows are popular because of the initial price. However, in the long run, cheap timber windows require twice as much maintenance and repairs compared to high-quality alternatives.
Maintenance of modern sash windows
We have touched on this topic in the previous section. As stated, modern premium timber windows are designed to last longer and resist the elements better than older windows or cheap modern alternatives.
Maintenance is still required. Although it is less extreme, you will likely need to repaint your windows every 5-8 years with no need for repair services.
While the frequency and type of upkeep may be less extreme than that required for older types of softwood sash windows, you will likely need to repaint your windows every 5-8 years in order to refresh the paintwork.
Overall, while advances in window technology have made maintenance a less intensive process than in the past, regular upkeep still plays an important part.
Can the original windows be upgraded to match the modern ones?
With the right materials and craftsmanship, it is possible to upgrade older sash windows to match modern ones, though this may require significant effort and knowledge.
Generally, upgrading older windows involves removing the original sashes and replacing the glass panes with vacuum-insulated glazing units that meet current energy efficiency standards.
By coating the frames with a layer of acetylated wood, you can double or triple their lifespan.
Another feature that is added during restoration is draught-proofing seals.
To sum it up, you can upgrade your older sash windows, but it’s not an easy job to do by yourself. You will probably need help from professional sash window specialists, especially if you live in a Grade 2 listed building.
David Prior
David Prior is the editor of Today News, responsible for the overall editorial strategy. He is an NCTJ-qualified journalist with over 20 years’ experience, and is also editor of the award-winning hyperlocal news title Altrincham Today. His LinkedIn profile is here.
