EWI presents a solution for
sustainable living inside and out
As well as helping form attractive, durable façades, external wall insulation (EWI) regulates interior
temperature to provide all-year-round comfort. However, EWI performance relies on appropriate
specification, according to Nikolaos Mantelis, product manager at Baumit UK, who looks at systems which
fit the bill when it comes to creating the ideal indoors environment
EWI is the ideal solution for
improved insulation performance.
Tried-and-tested over many
decades on projects around the
world, it provides a proven thermal
upgrade for properties old and new,
including individual houses, apartments,
and non-residential buildings.
A well-insulated property is crucial to
occupant health and wellbeing, as is the
purity of indoor air, particularly when
we inhale up to 13.5kg of interior air,
compared to 1.5kg of fresh air, per day.
Furthermore, with heating accounting
for 75% of the average household’s
energy bills, good thermal performance
fuelled by quality insulation provides a
proven template for sustainable,
cost-effective home living.
The most effective method for creating
a healthy living space is to optimally
insulate the façade – the better the
insulation, the more comfortable the
space will be.
The specification of quality EWI
can help achieve this level of interior
comfort, and it’s a solution that is
effective in multi-occupancy properties.
Through everyday living, residents
create water vapour. Now, consider how
much vapour is generated in a multioccupancy
building containing, say,
150 tenants. All that vapour will pass
through the building’s elements, but in
cases where the EWI system contains a
non-vapour permeable topcoat and
non-breathable insulation, the vapour
will be trapped. This can lead to
increased air humidity, condensation,
Therefore, an EWI solution that
might have appeared cost-effective in
on the outside
of a building,
as well as
OpenSystem comprises six vapour
permeable components. It includes
Baumit StarTop, a topcoat render that
provides optimum protection against
contamination with its quick drying
properties. The system is also made up of
Baumit PremiumPrimer and openTherm
EPS boards. When applied as part of a
newbuild or refurbishment project, each
component helps increase a structure’s
‘breathability’ to collectively offer
outstanding levels of insulation.
w www. baumit.co.uk
The world’s thinnest BBA certified
inverted roof insulation
Quantum Insulation has announced that it has secured
the distribution rights for Quantum PLUS+ Vacuum
Insulated Panel (VIP) insulation board, the only British
Board of Agrément (BBA) certified factory coated VIP
solution that is specifically designed for inverted roofs.
Suitable for use in new and existing domestic and
non-domestic flat roofs, including zero falls applications,
Quantum PLUS+ has a thermal conductivity of 0.007
W/m/K, making it the thinnest BBA-certified insulation for
any given target U-value.
the immediate-to-short-term, could
potentially result in unnecessary and
Applying non-breathable materials to a
building causes what might be referred
to as the “plastic bag effect” – walls can
become cloaked in condensation from
To create a breathable outer layer
for buildings, a silicon-based finish
render, such as Baumit’s SilikonTop, is
preferable. Water-repellent, stain and
weather resistant, the system provides a
robust white or coloured façade.
It’s easily applied to mineral renders
old and new, providing a decorative,
vapour-permeable topcoat that makes for
an attractive exterior, whilst optimising
occupants’ living environment.
For a damp and moisture-free,
healthy-living interior, Baumit’s range
of lime and silicate-based plasters
offer an excellent option. Due to their
vapour permeable properties and
being low in emissions, the range offers
plasters, which are ideal for interiors.
We spend 90% of our lives indoors,
therefore, providing a quality finish for
interior walls would appear paramount
to our wellbeing. There are a couple of
very good reasons for choosing EWI over
interior insulation, however.
Unlike the interior option, floor
space isn’t compromised with exterior
insulation. A few millimetres’ less living
room in a building containing multiple
flats and potentially hundreds of walls,
for instance, amounts to a sizable loss of
space, which for private landlords, could
mean a reduction in income.
Another benefit of ‘going external’
when it comes to wall insulation is
that EWI moves the dew-point – the
temperature at which water droplets
condense – to the outside of a building to
prevent condensation forming.
Baumit’s OpenSystem provides a
perfect example of an EWI system that is
breathable and retains airtightness.
Its perforated Expanded Polystyrene
façade insulation boards ensure high
vapour permeability, resulting in the
release, rather than the entrapment, of
44 www.rcimag.co.uk August 2020