BUILDING FOR THE FUTURE
Derek MacFarland, MD of IG Lintels explains why focusing on the fabric of the building is the essential fi rst
step toward carbon zero homes
Back in 2006, the government set an
ambitious target for all new homes being
built in the UK to be zero carbon by 2016.
The emphasis at the time was to make
sure that housing developments would incorporate
enough renewable energy sources to supply the
development with enough energy to heat and light
each house. So far, so sensible.
However, in the following two to three years,
housing starts fell by nearly two-thirds. For a
nation already suffering a housing shortage, drastic
action was needed. The government streamlined
the planning process and in 2015 went one step
further to “reduce the net burden on housebuilders”
by delaying the zero carbon homes target. Much
derided by environmental groups and consultancies
at the time, this decision could in fact be the making
of zero carbon strategy in this country.
What if the concept of offsetting energy
consumption with renewable technologies is
fl awed? What if the buildings themselves required
very little energy to heat in the fi rst place? What
if carbon zero homes could be achieved simply
by using better materials and products to create a
more effi cient building fabric?
It’s a school of thought that is gaining traction
BUILDING PRODUCTS | NOVEMBER 8
in construction. The NHBC Foundation, Zero
Carbon Hub, and The Energy Savings Trust have
all stated that a ‘fabric-fi rst’ approach is the surest
route toward zero carbon homes. They agree that
focusing on improving fabric U-values, reducing
thermal bridging, and improving airtightness
should be the fi rst step in reducing carbon
emissions from housing – before renewable energy
generation is considered.
Among the well-publicised advantages of a
fabric-fi rst approach are:
Adding sustainable energy generating equipment
to a site can be expensive and it’s been proven
that fabric-fi rst measures achieve equivalent CO2
savings for less.
The NHBC Foundation estimates that
fabric-fi rst energy effi ciency measures cost
£124 per tonne of CO2 saved, while bolting
on renewables costs £525. Reducing the
equivalent CO2 at a quarter of the cost is
There is a question mark over the true
sustainability of renewables, as much of the
technology requires regular maintenance and
even replacement over the life of the building.
Photovoltaic panels, for example, require
replacement inverters around two to three times
over the 25-40 year lifespan of the panels. They
also require regular cleaning to maintain effi ciency,
which would likely have to be carried out by a
specialist cleaner with equipment to reach the roof.
All this adds up to a quite considerable
cost that may not be evident to
potential buyers. Fabric-
a considerable saving for