Historic Range Specification Guide

Due to the variation in window styles, listed building requirements and planning authority interpretation, we have created a very wide range of options to ensure that we can meet the optimal requirements for any project.

To specify the optimum design, we have produced a flowchart. This starts with the best performance the lowest cost (a solution that works for about 75% of projects we have been involved with), with the cost/performance then affected as more strict aesthetics are specified further down the chart. We are able to quote for multiple options to provide you with more precise details. The flowchart below gives more details on the glazing method, performance and cost of our options.


 

System 1: Internal Bead with Astragal bar

Narrow sash and frame profiles and all of our historic features but using a modern internally glazed design for optimal performance.

Historic Window System 1Glazing Method: Internally beaded using advanced system from traditional range.
Glazing Bar: 21mm astragal bar (with interbar as option)
Performance: *****
Cost: ££
Options: Sash Bead Profile, Astragal Bar Profile, Standard Glass.


 

System 2: External Bead with Astragal Bar

Changing to an externally glazed system more accurately replicates the original designs, but loses many of the performance advantages of modern internally beaded design.

Historic Window System 2Glazing Method: Externally beaded
Glazing Bar: 21mm astragal bar matching historic sash profiles
Performance: ***
Cost: £££
Options: Historic Sash Profile, Historic Astragal Bar, Historic Glass


 

System 3: External Bead with Structural Glazing Bar

As System 2 but with a traditional structural glazing bar. As this requires separate glazing panels rather than a single unit, there are more thermal shortcuts and it requires more time to glaze the window.

Historic Window System 3Glazing Method: Externally beaded
Glazing Bar: 21mm (single glazing) / 24mm (double glazing) solid glazing bar
Performance: **
Cost: ££££
Options: Historic Sash Profile, Historic Glazing Bar, Historic Glass


 

System 4: External Putty with Structural Glazing Bar

As System 3 but glass is installed with putty rather than a bead. This replicates the aesthetics and the production methods of the original product but is the highest cost option with reduced performance and guarantees.

Historic Window System 4Glazing Method: Externally face puttied
Glazing Bar: 21mm (single glazed) / 24mm (double glazed) solid glazing bar
Performance: *
Cost: £££££
Options: Historic Sash Profile, Historic Glazing Bar, Historic Glass


View our Historic Range.