Glidevale
Protect, one of the UK’s leading manufacturers of external wall breather
membranes, welcomes the recent updates to Structural Timber Association’s STA
Advice Note 18 which highlight the importance of providing specifiers with trusted,
and tested, technical product information.
First launched
in 2019, STA Advice Note 18 – ‘Breather membranes to structural walls’ is a
valuable resource for contractors and specifiers involved in structural timber
construction projects and the wider offsite construction market.
The guide
provides detailed information on the use of breather membranes in terms of
watertightness, exposure, thermal performance and fixing requirements.
The new
amendments to the document were published in April 2023 and have been compiled
in collaboration with several specialist manufacturers including
representatives from Glidevale Protect.
The revised
STA Advice Note 18 provides enhanced guidance on watertightness and
specifically the use of W1 and W2 rated external breather membranes. A new
section on ‘site-specific exposure to wind-driven rain’ aims to clarify how to
assess if a site is in a very severe area and if it would require a W1 rated
breather membrane to provide the necessary resistance against water penetration.
Guidance maps from BRE and NHBC are also included to highlight very severe
areas of the UK where a W1 membrane is recommended.
As one of the
contributors to both the original and revised STA Advice Note 18, Glidevale
Protect is well placed to assist specifiers and designers in choosing the most
appropriate product for their project and offers a full range of both W1 and W2
rated reflective and non-reflective breather membranes for external walls.
As outlined in
the original version of the STA Advice Note 18, the new guidance looks
specifically at the specification and installation of external breather
membranes for cavity facing structural wall panels. The recent updates
highlight the need for all manufacturers to be able to verify all product
claims, including for reflective membranes to be tested to BS EN 15976 and to
claim aged thermal resistance figures which are fully independently certified
by a third-party accredited body.
Glidevale
Protect is committed to providing full technical transparency to its customers
and fully supports the renewed focus on providing specifiers with reliable
technical information for external membranes which accurately reflects real
life performance figures. In compliance STA Advice Note 18, its product range
of external breather membranes is tested and certified by a UKAS accredited,
independent third party. In line with the recommendations outlined in the
guidance, Glidevale Protect is also a passionate advocate of improving the way
manufacturers communicate the technical performance of a product and
specifically, clarifying if the quoted figures are based on aged or unaged
values.
As well as
providing full transparency on the testing of its products, Glidevale Protect’s
best practice ensures all its results take into account any brand printing on
the low-emissivity surface and in addition, the aged thermal resistance values
achieved are based on the membrane installed with the appropriate maximum
horizontal fixing centres of 600mm, both which are detailed in STA Advice Note
18.
Specifiers can
obtain a copy of the STA Advice Note 18 by contacting Glidevale Protect’s
technical team directly at info@glidevaleprotect.com
or by calling +44 (0)161 905 5700.
Further
guidance on the specification of external breather membranes as part of the
wall, floor or roof build-up within structural timber construction, including
free U-value calculations condensation risk analysis and take offs, is also
available from Glidevale Protect’s technical team. For more information, please
visit the website or follow
Glidevale Protect on LinkedIn.
