Retrofit Double Glazing

New vs Existing Sashes

Some retrofit services adapt existing sashes (the sash is the timber frame that holds the glass in place) by removing old glass and modifying the timber to accommodate double glazing. In many cases, older sashes may have experienced movement or wear over time, which can affect long term performance.

 

At Woodworkshop, new cedar sashes are manufactured and glazed in our workshop using a BRANZ approved system. This controlled process supports accuracy, durability and a cleaner finish, with sashes supplied primed if required.

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Quality joinery and materials

Our retrofit sashes are manufactured from clear cedar including Western Red or Alaskan Yellow, with stainless steel fixings and hinges, mortise and tenon joinery and polyurethane glue for durability. Double glazing units are supplied with a ten year warranty and installed using a BRANZ approved system.

 

With stable timbers and quality joinery methods, these new sashes are built for long term performance and, when properly maintained, can last for many decades, often comparable to the lifespan of original timber joinery.

 

Existing sashes can remain in place until replacement day, avoiding exposed openings or temporary boarding.

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Weight and Operation

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Double glazing is significantly heavier than traditional single glazing, particularly for opening sashes. Older sashes were not always designed to carry this additional weight, which can lead to operational issues or increased wear over time.

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Manufacturing new sashes specifically for double glazing helps ensure balanced operation, smooth movement and reliable long term performance.

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