From colourful terraces in Totterdown to period townhouses in Clifton and family homes across Bedminster and Bishopston, Bristol properties are wonderfully varied. That’s why choosing between double glazing and secondary glazing isn’t always a cut-and-dry decision.

In simple terms:

• Double glazing replaces your existing windows with brand new sealed units made up of two panes of glass.
• Secondary glazing keeps your original window in place and adds a discreet second layer on the inside.

Both reduce heat loss, improve energy efficiency and cut noise levels. However, each have certain nuances which may make one more suited to your property. For instance, secondary glazing is often the better choice for older or protected properties, and double glazing is wisest if a new look and the best possible thermal performance are your top priorities.

Introducing secondary glazing Bristol: How does it differ from standard double glazing?

Secondary glazing involves installing a slim additional glass frame next to your existing window, meaning you don’t need a full replacement, a cost-effective solution. A gap is deliberately left between the primary window and second layer, acting as thermal insulation and improving acoustic performance.

Our secondary glazing features a strong, slim and unobtrusive aluminium profile, reducing noise by up to 10%, and even achieving 10% more thermal insulation than double glazing in certain circumstances.

At DM Windows, our secondary glazing products are manufactured by Granada, industry specialists producing over 25,000 frames each year.

Key differences

• Secondary glazing
  • Keeps your original window
  • Installed internally
  • Often no planning permission required
  • More cost effective
  • Excellent sound and thermal insulation
• Double glazing
  • Fully replaces existing windows
  • Sealed two-pane unit
  • Strong thermal efficiency
  • Wider style and material choices

Comparison table

Is secondary glazing worthwhile for my home?

There are situations where secondary glazing is a particularly effective solution. While double glazing remains the popular choice for many properties, secondary glazing solutions are ideal in specific circumstances.

If you live in a period or listed property

Bristol has many period properties and conservation areas. If you’re required to retain original timber windows or sash windows, replacing them with new double glazing may not be permitted.

Secondary glazing allows you to:

• Keep original features intact
• Improve thermal performance
• Boost acoustic insulation
• Maintain the external appearance

Because it is internal and reversible, it is often approved where full replacement is not.

If you want thermal performance on a budget

Secondary glazing creates a thermal barrier. The air gap reduces heat transfer, helping lower heating bills during the winter months. It makes a significant difference at a fraction of the cost of double or triple glazing, and the difference in performance is usually minimal.

For homeowners concerned about rising energy bills and carbon footprint, it’s a practical compromise.

If planning permission is a concern

In many conservation areas, changing the external appearance of windows requires approval.

Secondary glazing rarely needs planning permission because it does not alter the exterior. If your existing windows are in good condition but underperforming, this can be the simplest route.

If noise reduction is your main goal

Homes near busy roads often suffer from traffic noise and general noise pollution.

Granada secondary glazing can reduce noise levels by up to 80%. The larger gap between panes can even outperform standard double glazing in terms of acoustic performance. For many Bristol homeowners, this creates a huge difference in day-to-day comfort.

Where double glazing may still be your best bet

Secondary glazing is not always the right answer. There are clear cases where new double glazing is the better long-term solution.

Thermal performance is still valued

Truth be told, both secondary glazing and modern double glazing have industry-leading performance when it comes to thermal efficiency. The stronger choice will largely depend on which materials are in play, and how they are fitted.

You can rest assured that if you choose aluminium or uPVC glazing from DM Windows, you can enjoy lower energy bills as well as a naturally more comfortable space.

If your frames are damaged

If your frames are warped, rotting or draughty, adding a second layer will not fix structural problems. Replacing them with new uPVC or aluminium windows ensures long-term reliability and security.

If you want a complete window upgrade

If you would like to change the style, material or colour of your windows, full replacement is the right option.

We install:

• Casement windows
• Sliding sash windows
• Bay and bow windows
• Tilt & turn windows
• Flush sash and heritage styles
• Residence Collection windows

Available in over 60 uPVC colours and more than 100 RAL aluminium finishes.

The bottom line

Secondary glazing from DM Windows

Our secondary glazing Bristol installations are slim, discreet and made to measure. We offer horizontal sliding, vertical sliding and hinged units in a wide choice of RAL colours.

Installation is quick, tidy and carried out by our experienced team with excellent customer service from start to finish.

Double glazing from DM Windows

As CERTASS certified installers, our double glazing meets the latest Building Regulations. We use high quality uPVC and Aluminium systems sourced from trusted local manufacturers.

With double and triple glazing options, decorative detailing and a broad range of colours, we provide professional installation designed to deliver long-lasting thermal efficiency and security.

Who are DM Windows?

We are DM Windows, based at 11-16 Cater Road, Bristol, BS13 7TW. We serve Bristol and the surrounding areas, working with homeowners and commercial clients alike.

As CERTASS certified and SafeContractor approved installers, we combine first class workmanship with friendly, reliable service. From secondary glazing and double glazing to doors and conservatories, we support you from design through to aftercare.

If you’re unsure which option suits your home, call us on 0117 313 6884, email sales@dmwindowsbristol.com or request an online quote today. We’re here to help you make the right decision.