ROOFING, CLADDING & INSULATION
BUILDING FOR HEALTH
Roofing – sarking
Sarking boards are typically softwood boards that
are fixed to the rafters of a roof to add extra strength
to the structure of a building. Where a roof has a
pitch of 16º or greater, sarking panels prevent water
from entering a building and thus can provide
temporary protection for a building before slates or
tiles are added.
Natural sarking provides a roof with thermal
insulation, improving the energy efficiency of a
building by up to 25%. It also reduces the risk of
indoor air pollution by preventing the build-up of
damp and condensation – which impact the overall
health and long-term performance of a building.
This helps to keep a building’s occupants in
good physical health as effective moisture control
prevents the growth of mould or bacteria.
Due to this and other health benefits, sarking is
required by law in most parts of Australia
Natural wood fibre panels are quick and easy to
install – their tongue and groove profile enables
them to form a strong bond with other panels,
producing a windtight connection and improving
This seamless connection not only contributes
to a higher indoor air quality but also to a higher
quality acoustic environment, acting as a buffer
for both external and internal sound. Research has
proven that natural materials can help to better
BUILDING PRODUCTS | FEBRUARY
Making beer decisions when choosing construction products,
processes and techniques is the key to creating healthy buildings
according to Adrian Judd, director at Steico. Here, he explains three
simple ways to provide immediate benefits in terms of occupant health
and the overall environment – both internally and externally – through
choice of roofing, insulation and sheathing.
keep out noise pollutants such as music, traffic or
other transport (European Commission, 2011).
Sarking boards can be cut using traditional
woodcutting tools and they are both light and easy
Typically, insulation is associated with the retention
of heat contributing towards an energy-efficient
building. However, it has a significant role in
preventing heat from entering a building.
Wood fibre insulation is made using sustainablyprocessed
timber and it provides moisture control
and vapour permeability to a building. It is also
easier to dispose of as it can be recycled and
repurposed, limiting waste.
Natural insulation, such as wood fibre, also
has thermal-regulating properties ensuring the
temperature of a building remains comfortable.
As wood fibre insulation is vapor-permeable, it
makes for a healthier internal environment as it
helps a building ‘breathe’.
This ‘breathability’ is paramount in preventing
harmful water building up in a building. It also
lowers the health risks for those who suffer from
respiratory conditions such as asthma or chronic
obstructive pulmonary disease (COPD).
In countries which are already building in this
sustainable and healthy way, such as Denmark
or Finland, the health of a building’s internal
environment is governed by regulations. Currently,
no such alternative exists in the UK.
In the same way as sarking, wood fibre insulation
also contributes to a higher quality acoustic
environment, an improved indoor air quality and
greater energy-efficiency within a building.
Sheathing is a board or panel that acts to form a
strong structural surface onto which other materials
used to sark an
Roof constructed with Steico
Ijoist structural elements,
sheathed with Steico Special
and fully filled with Steico Zell
air injected blown insulation
credit Kithurst Builders