EVS Draught Seal

Retro Triple Glazing

Retro glazing older character homes usually involves removing existing glass and sometimes character features such as astragals and lead-light windows. The EVS Triple Retro glazing system simply adds a double glazed panel to the outside which allows the original glass and character features to remain. This saves time and delivers higher performance insulation and protection.    

Triple Retro Glazing

Triple Retro Glazing is a whole new way to enhance existing windows that maximize the insulation and protection while reducing the time and invasive installation process. The EVS panels can be fitted with most types of glass combinations and can be tailored to the customer's requirements and budget. Most commonly Low-e Glass is used to achieve the high performance insulation, whereas standard glass can provide more heating from the sun.

EVS uses thermal pumping technology

The key to the EVS technology is using thermal pumping as a way to remove trapped moisture that collects between the existing and new panel. As the panel heats up during the day, the warm air mobilizes the trapped moisture which rises to the top of the panel where it is pumped out through the top vents by the action of heat expansion. As the panel cools down, the opposite happens and it contracts and draws in external dryer air.

The vents use the unique qualities of Bentonite clay that can absorb moisture from the air, but unlike other synthetic desiccates Bentonite clay can release the moisture at low temperatures allowing the moisture to be captured in cool temperatures and released when the panel warms up.   

EVS Triple Glazing for Casement Windows

Casement windows are the most common window fitted with EVS Triple Glazing panels which achieves high performance insulation and protection of the existing character elements. 

EVS Draught Seal

EVS has developed this unique system to ensure any trapped moisture can be released and not build up between the panels and cause fogging. The process is called thermal pumping that uses the cycle of warm and cold to breath in cool dry air and expel warm moist air and promote a dry cavity between the existing glass and new glass panel. The panel is clipped to the surface of the existing timber sash and is sealed and painted so that it integrates into the style of the existing joinery.  It is recommended that opening panels are also fitted with EVS Draught Stop to achieve the best performance result.

View BRANZ Appraisal  

EVS Triple Glazing for
Double Hung Windows

Double Hung windows can also be fitted with EVS Triple Glazing Panels to achieve high performance insulated panels and protect the character of existing windows.  

EVS Draught Seal

EVS has developed a number of solutions for triple glazing Double Hung windows from awning opening to traditional weighted window slide opening panels. They are a more complex window system and require more work compared to fitting standard casement style windows. The biggest consideration is preserving the original character while delivering the highest performance. It is recommended that a window set only needs one or two opening panels to reduce draughts and cost. The windows are also given a health check and repaired where rot has been discovered to ensure that window provides ongoing service.

Find out more Triple Glazing Solutions  

-Double Hung windows
-Curved Shaped windows
-Lead-light windows
-Fanlight Windows
-Astragal Windows
-Casement Windows
-Thin-Edge Windows
-Direct Glazed Windows

You can download your copy of the EVS Triple Glazing Brochure for all the information about how Triple Glazing can improve your home

EVS Triple Glazing Brochure

BRANZ Appraised
EVS WINDOW TECHNOLOGY LYD is pleased to announce that their Retro Triple Glazing system has passed all of its tests and gained its appraisal from the Building Research Association of New Zealand. This has been an important step in providing the customers and the Glazing industry with assurance that the triple glazing system meets the NZ Building Code's standard. It has demonstrated outstanding performance in thermal, aging and wind load testing.
Find out More 

Thermal Performance

Research shows that warmth and insulation are some of the highest priorities when deciding on upgrading your windows. EVS has engaged the services of BRANZ to carry out a full appraisal of our Triple Retro Glazing system, to show the thermal modelling and performance.  

BRANZ (Building Research Association of New Zealand) has been working on completing a Thermal Modelling report to show the R-Value (Insulation Value) of the standard configurations of the EVS Triple Glazing system. (Click on the buttons above for more information)


Existing single glazed window

The low insulation value of (R0.19) on single glazed panels causes heat loss and condensation in poorly vented rooms. Upgrading with retro glazing will improve your single glazed window.

Triple Retro Glazing (Standard)

The EVS Triple Retro Glazing fitted with standard glazing (R0.45) still has a high insulation value compared to Aluminum double glazing (R0.26). It is ideal for allowing the sun to warm your home. 

Triple Retro Glazing (Low-E Argon)

EVS Triple Retro glazing fitted with Low-E argon panels takes out first place (R0.59) for a retro fitted window solutions. The Low-E provides higher insulation against heat loss as well as heat gain. 

Dunedin and Otago Agent

Talk to us about your Retro Glazing project. For locations around the rest of New Zealand we can organise local installers for your project

Phone: +64 (0) 274346912
Email: info@evsglazing.nz

EVS Head Office 

EVS Window Technology Ltd
122 Kaituki Ridge Lane
Queensberry Hills
Central Otago 
New Zealand


Email: info@evsglazing.nz
Draught Stop orders Sales@evsdraughtstop.nz

Mobile: +64 (0) 27 4346 912