Skip to content
CosyGlazing, allows you to enhance your existing windows, open them in smoothly summer, reduce energy bills and stay warmer in winter
CosyGlazing is and advanced secondary glazing system developed and tested over seven years that is elegant, effective and unobtrusive. We use plexiglass – a modern, lightweight equivalent to glass that’s used in the aeronautical industry – to provide a second layer to your period windows.
Our secondary glazing is unobtrusive and smart. In can be supplied in white or in a wooden frame to complement your Hertfordshire property. We can even paint it in a Farrow & Ball tone to match your existing windows.
In addition to installing CosyGlazing we also provide a full window restoration service. We will leave you with stunningly restored and painted windows with matching secondary glazing and smart fittings that will find you looking at your windows as much as looking through them.
Our innovative secondary glazing and insulation solutions are well suited to preserving Hertfordshire’s celebrated architecture, fine examples of which can be found in areas such as Watford, Hemel Hempstead, Stevenage, St Albans, Cheshunt plus other areas in this magnificent county.
Can I install CosyGlazing in my listed building?
Yes. Conservation officers love CosyGlazing because it’s both reversible (you can take it out, leaving your windows intact and unaltered) and invisible from the outside which makes it approved for listed buildings. It’s virtually invisible from the inside too, which means your beautiful listed windows will still look stunning while keeping your home warmer.
Nine out of 10 conservation officers across southern England agree that CosyGlazing does not require listed building consent for Grade I , Grade II or Grade II* listed buildings. However, we always recommend that you contact your conservation officer to get their view. Very occasionally they will ask homeowners to file a Listed Building Consent Application (which is free), however we have never had an application turned down. The main reason for this is that CosyGlazing preserves the historic fabric of the windows, is virtually invisible and allows you to open your windows as usual. If the installation of CosyGlazing also involves refurbishing the window, it lasts even longer which preserves the architectural heritage.
If you have concerns, we are happy to make a discrete enquiry with your conservation officer on your behalf, and also can manage your application process if you wish.
- CosyGlazing is perfect for sash windows in period homes and listed properties
- CosyGlazing reduces heat loss from single glazed windows by 70%
- CosyGlazing fits to every type of window and you can open your windows as usual
- CosyGlazing is removable and invisible from the outside and so conforms to conservation requirements for Grade 1 and Grade 2 listed buildings
The solution for period homes and listed properties
The CosyGlazing Secondary Glazing system was designed specifically for period homes and listed properties. We have a huge amount of experience installing secondary glazing to older properties across the South and West. One major advantage of our system is that it helps improve the thermal properties of your windows without losing their aesthetic appeal.
With our teams of craftsmen, we work for owners of listed and period properties across the South, West and Midlands. Our innovative secondary glazing and insulation solutions are well suited to preserving Hertfordshire’s celebrated architecture, fine examples of which can be found in areas such as Watford, Hemel Hempstead, Stevenage, St Albans, Cheshunt plus other areas in this magnificent county.
More than just secondary glazing
There are several energy-saving solutions suitable for period and listed properties to make them warmer and more cost-efficient to run.
- Secondary glazing: The prospect of battening your beautiful heritage windows behind secondary glazing can be off-putting but Mitchell & Dickinson’s CosyGlazing system is virtually invisible. It can be unobtrusively fitted to the glazing in your doors and windows. Sash windows and casement windows can still be opened in the same way they always have, and the systems can be painted to blend in with your colour scheme.
- Draught proofing: Draughts from windows and doors and suspended floors can all be effectively excluded, using measures that can be seamlessly incorporated into your home. Old properties do need some ventilation though, so it’s important to retain a level of natural ventilation unless fitting mechanical ventilation. Our draught proofing is designed to cut draughts by 70% to ensure a natural level of ventilation. Listed properties ventilated to 2050 standards will need to have mechanical ventilation systems fitted, in line with the ‘build tight, ventilate right’ maxim. These are more energy efficient than natural ventilation methods and improve indoor air quality.
- Loft insulation: Sheep’s wool insulation is a great option for the loft. It’s 12% more efficient than mineral wool, supports British farmers, is more resilient and bounces back when it’s been squashed. If insulating between the rafters to recreate a warm loft, breathable insulation boards (50mm minimum but ideally 100mm) are the most effective option.
- Floor insulation: If you have a cellar or an accessible underfloor void, a breathable mineral or sheep’s wool insulation can be affixed to the underside of the floor above. Where there’s no cellar but your underfloor void is accessible, breathable insulation can sometimes be suspended beneath the floorboards.
- Internal wall insulation: We create a lot of moisture through breathing and using our bathrooms and cooking, so it’s important to allow this movement of moisture through the wall. In the same way, heritage buildings often have a degree of rising damp, so it’s important not to trap it. Cork lime render like Diathonite applied directly to the internal wall, with no gap, is a good solution.
- External wall insulation: It’s possible to get Listed Building Consent for external insulation if the building is rendered and it’s done well. Wood-fibre insulation boards like DIFFUTHERM, and hemplime or hempcrete boards, are a good solution for period properties, with a moisture-permeable render such as a lime render.
