September 2020

Regulations
ENERGY EFFICIENCY & NEW BUILDS
The experts at A Proctor Group ask ‘does energy efficiency only matter for new build
properties?’
Clearly regulations for energy efficiency
relate to both new build and
refurbishment, but should they not allow a
relaxation in refurbishment that takes into
account the difficulties of meeting this level due
to aspects such as floor zones etc? Regulations
for acoustics take into account new build
properties and the difficulties of existing
buildings, so why don’t we for energy efficiency?
When we get to the ‘other side’ of Coronavirus,
the way we come out will be different; we will
unlikely go back to the ‘old norm’. The effect of
Coronavirus will have rebooted the way we think
about various things such as, what’s important in
life, appreciation of what we have, and the effects
of climate change.
So, is it time for the government to look at the
existing housing stock and assess how their
efficiency can be improved? – the same way as Part
E and Section 5 recognise, instead of hammering
the easy target of new build properties where the
targets set provide the new minimum requirement
to design down to as cheaply as possible, rather
than a worse case minimum.
As stated, Part E and section 5, acoustic regulations
are considerate of the difficulties of trying to design
existing buildings with its existing issues to the
same performance levels of new builds built from
scratch. With acoustics, even in refurbishment the
acoustic measures will invariably be better than
before, but with thermal improvements there could
be knock-on effects such as structural damage due
to hidden moisture issues from trying to improve the
building’s energy performance. Therefore, a good
understanding of HAMM (Heat, Air and Moisture
Movement) are critical to get the balance of
improved energy efficiency with moisture issues.
The government aims to reduce green house gas
emissions by 80% by 2050 and this requires a
change of emphasis which goes
away from just new build to
looking at existing housing stock.
This would provide not just reduced
emissions, but potentially less burden on
the NHS and lower living costs to heat homes. We
must be considerate of what the placement of
insulation would have in old homes – one issue
being solid wall homes.
A good option
Solid walls have been a good choice through the
years for a country that lives in a climate where
there is a lot of rain. These walls can be built
thicker, depending on their exposure to rain to
reduce the amount of water penetrating the external
wall. These walls were traditionally built of stone
work in such a way that they also “breathed”,
thereby drying the walls when the climate allowed
which can be effective but not efficient thermally.
According to NIA, the current housing stock in the
UK stands at 24.5 million dwellings. Of these, 6.6
million properties have solid walls which represent
31% of the total housing stock; 48% of the 326,000
high rise flats in England have solid walls. These
solid walls are deemed hard to treat as they cannot
benefit from the easier energy efficient method of
cavity fill. They can only be treated internally with
internal wall insulation (IWI) or with external wall
insulation (EWI). Both of these options come with
the benefit of potentially improving the insulation
levels in the dwellings but with more difficulties,
especially with internally applied insulation.
With IWI, more does not always mean better and
there is a real case for balancing energy efficiency
with good moisture control and understanding. In its
most simplistic form, more insulation (thicker) will
come at the expense of space internally, in some
cases making double bedrooms into singles and
singles into box rooms. So we strive for more energy
Left: Spacetherm from A Proctor.
efficient insulation to reduce the
thickness required which can be an efficient
option, but this can compromise the vapour
permeability of the wall and reduce its
“breathability”. In most cases, the strive for more
efficient thermal insulation at a lower thickness
needs to compromise the vapour permeability and
the constant balancing of these factors becomes an
ever-increasing conundrum – until recently.
Now you can balance improving the thermal
efficiency, decrease water absorption and maintain
the intended breathability with the introduction of
nano technology called Spacetherm insulation. Our
Spacetherm insulation gives high levels of thermal
insulation with a low thermal conductivity of 0.019
W/mK while still offering breathability and
exceptional levels of water repellence. Solid wall
properties can be transformed with thin insulation
in terms of green house gas emissions, yet without
a vast reduction in room size.
The Spacetherm WL board comes in just 13mm
thickness including the 3mm MgO hard wearing
surface which is adhesively bonded to the wall. This
can reduce a solid wall U-value from 1.5 W/m²K
(and in some cases 2.1 W/m²K) to below 0.7
W/m²K. This is halving the heat loss through a solid
wall at around half an inch thick! If the government
was to relax the conversion levels to this level, then
nearly a third of the UK’s existing housing stock can
reduce its heat loss dramatically without major
disruption to properties, whilst still maintaining
the structural integrity due to the breathing wall
and less risk of built-in moisture issues from vast
changes in a structure’s temperature, and
therefore in-built condensation problems.
Contact A Proctor Group
www.proctorgroup.com
@proctorgroup
56 TC SEPTEMBER 2020