8 over 8 and 6 over 6 Sash Windows Can be Double Glazed – A Guide

8 over 8 and 6 over 6 Sash Windows Can be Double Glazed – A Guide

There’s something truly special about 6 over 6 and 8 over 8 sash windows — their timeless symmetry and handcrafted beauty bring warmth and charm to any home. Often featured in Georgian and Victorian period houses, these windows carry a heritage appeal that can’t be replicated. However, traditional single glazing often leads to drafts and heat loss, which can affect comfort and higher energy bills. Fortunately, sash windows can be double glazed. Double glazing offers a way to improve insulation without changing the classic look of these windows. With sash window specialists like Six over Six windows, it’s possible to enjoy modern insulation benefits while preserving the character of your period windows.

Types of Sash Windows

Sash windows come in a few classic styles, each adding a unique touch of history and charm to period homes.

Georgian Sash Windows

Georgian sash windows are known for their timeless 6 over 6 or 8 over 8 pane designs. Small individual panes, divided by slim glazing bars, create that elegant, balanced look typical of the Georgian era. It’s all about symmetry and subtle detail, adding a refined touch to any home.

Edwardian Sash Windows

Edwardian sash windows bring a lighter feel, often with larger panes and fewer glazing bars, like the 6 over 2 style. These windows also allow more sunlight to pour in, making them perfect for the airy interiors that defined the Edwardian period.

Box Sash vs. Traditional Sash Windows

Box sash windows use weights and pulleys inside a “box” frame for smooth opening. They are especially common in Georgian and Victorian homes. Traditional sash windows, on the other hand, might use spring balances. This offers a similar look but easier to fit in modern homes.

How Double Glazing Works for Sash Windows

For sash windows with classic glazing bars, like 8 over 8 or 6 over 6 patterns, double glazing can be achieved without needing a full replacement. This careful process preserves your windows’ original charm while enhancing insulation. Here’s how it works:

1. Preparing the Window: Each sash is gently removed to inspect the window frame’s structure and condition. The goal is to determine whether it can support a double-glazed unit and to make any small adjustments necessary for a secure fit.
2. Removing the Existing Single Glazing: The old panes of glass are carefully removed, including any putty or beading, while preserving the glazing bars and frame structure.
3. Modifying the Sash to Fit Double Glazing: The sash is precisely altered by creating a channel along the edges to fit the thicker double-glazed unit. For windows with multiple glass panes (like 8 over 8 or 6 over 6), only the exterior side of each glazing bar is trimmed. This is done to accommodate the new double glazing, keeping the iconic internal design visible.
4. Installing the Double Glazed Unit: The new double glazed pane, often a thin-profile or vacuum-insulated glass for period properties, is carefully fitted into the sash to avoid structural changes to the frame.
5. Securing the Glass: The new glass is set with fresh putty or beading. This ensures a draft-free fit, matching the traditional look.
6. Rebalancing the Sash: Since double glazed panes are heavier than single glazing, sash weights or sash cords are adjusted for smooth operation. This allows the window to open and close as it originally would.

Choosing the Right Double Glazing for Period Wooden Sash Windows

Not all double glazing options are the same, especially for period sash windows. Some types are better for keeping the home’s traditional charm while also boosting comfort. Here are the best types to consider:

• Vacuum Double Glazing: Ideal for period properties, vacuum double glazing offers the insulation of double glazing in a thinner pane. A vacuum layer between the panes means it fits narrow frames, preserving the look of original sash windows.
• Low-E (Low-Emissivity) Double Glazing: Low-E glass has a nearly invisible coating that reflects heat back into the room. This boosts insulation while letting natural light pass through each glass panel and reducing heat loss.
• Acoustic Double Glazing: For those in noisy areas, acoustic double glazing reduces sound. This is achieved with thicker or laminated glass, keeping your home quiet.
• Tinted Glass: Tinted glass provides privacy and UV protection. It’s great for reducing glare in bright rooms.
• Toughened Glass: Toughened glass, built to withstand impact, is ideal for high-traffic areas or lower-level windows. It also adds durability to original timber sash windows without sacrificing style.

Conclusion – Sash Windows Can be Double Glazed

Double glazing your 8 over 8 and 6 over 6 sash windows doesn’t mean losing the charm and character of your period home. With thoughtful techniques and the right types of glazing, you can boost insulation, reduce noise, and increase comfort—all while keeping the look you love. It’s a practical way to enjoy the benefits of modern energy efficiency without sacrificing historic appeal. If you’re seeking that perfect balance of style and function, double glazing might be the upgrade your windows have been waiting for.

Guest Article.