The benefits of combining off-site construction with external wall insulation (EWI) are explored in a technical document produced by the British Board of Agrément in conjunction with EWI specialist STO.
Aimed
at specifiers, contractors and end clients, the literature outlines the
many benefits of marrying the two solutions, from energy efficiency to
time savings and increased build quality to improved on-site health and safety.
“EWIs and off-site construction are perfect
partners when system selection, design and testing are key
considerations,” said BBA Test Services product manager George Bailey,
who co-authored the document with David Tyndall, STO Director - Off-Site Construction Solutions (Western Europe). “EWIs can be applied to a wide range of off-site
modular and panellised structures including timber, SIPS, reinforced
concrete and various steel-based options that are proving increasingly
popular for large multi-storey buildings.
“Durability,
thermal performance and long-term aesthetics rely on the performance of
the system as a whole…performance is achieved through multiple
components working together,” added Mr Bailey. "Therefore when
considering design changes or multiple external finishes, careful
attention must be paid to the implications these alternations may have
on performance.”
The
literature also discusses technical elements to take into account, for
example the spacing of structural elements within each modular unit to
accommodate mechanical fixings and planning the EWI early in order to
determine the entire system’s performance through structural and
environmental testing.
Manufacturers
offer numerous types of EWI, including EPS, XPS, mineral wool, PIR, PUR
and phenolic foam. This variety of material type and usage means there
is no standard method of testing and assessing systems; careful
consideration is therefore required to select from test requirements
including fire and thermal performance, watertightness, resistance to
wind loading and structural testing.
“EWI
products should be supported by robust testing carried out buy a
UKAS-accredited testing facility such as the BBA,” said Mr Bailey. “The
work of the BBA in establishing certification and testing parameters for
EWIs has led to European-wide regulation with EOTA and provided guidance to the UK government.”
To view the document, visit: https://www.bbacerts.co.uk/uploads/cmsfiles/Industry_voices_STO_web.pdf
