Issue 41 Spring web - Flipbook - Page 54
Standard glass
Hard coat low E-glass
High performance sealed units
Heat loss reduction
50%
65%
75%
U-Values W/M2K
Single glazed metal window
5.4
Single glazed timber window
4.7
Secondary glazing standard glass
2.6 – 2.9
Secondary glazing low-E glass
1.8 – 1.95
Secondary glazing sealed units
1.6 – 1.7
Secondary glazing with high
performance sealed units
1.27 – 1.35
Sympathetic design
Selectaglaze secondary glazing is designed to provide the
right performance with minimal visual impact on
the character and design of the original building - both
externally and internally. For ecclesiastical buildings, this
requires custom made units able to reflect the diverse
range of gothic arch, circular and other shaped windows.
When these include important stained glass panels
anti-reflective glass can be included to maintain clarity.
Above, sensitive retrofit solutions for listed buildings
Specification
Specifying secondary glazing is a complex process and involves a multitude of design, performance and regulatory
considerations. Selectaglaze offers free comprehensive
consultation on specific projects and a range of RIBA
approved CPDs.
PRECISION BESPOKE SECONDARY GLAZING
www.selectaglaze.co.uk
Below, sympathetic secondary glazing, with no additional sightlines
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