INSULATION
Increasing the amount of insulation in a building has been named as one of the most simple and cost-effective energy efficiency measures to achieve savings in a report by Climateworks Australia.
The benefits of ensuring a commercial building is well-insulated are wide-ranging. It improves the overall performance of the building, reduces harmful greenhouse gas emissions and helps keep power bills down.
Kingspan Technical Services manager Killian Smith says that any initial investment in insulating commercial buildings can be “easily recouped” in savings from energy costs. “Thermally-efficient commercial buildings that achieve a verified performance standard deliver better occupant comfort and in turn command higher rental fees. More energy efficient buildings can deliver higher resilience to extreme weather, better comfort, and reduce stress on the electricity grid.”
And it’s not just your power bill that will improve, Smith says. “It has been proven that energy-efficient buildings provide a better working environment, help increase productivity, and provide health benefits for their occupants.”
“Good insulation is crucial for the overall performance of any building and the wellbeing of its occupants, be it a commercial or a residential building.”
CHOOSING THE RIGHT SOLUTION
With new materials emerging all the time, it is becoming harder to keep up to date with what products are out there, and even harder to understand the finer details of each one, Smith says.
“When specifying, it is important to know that the products you are including are going to give you the performance you seek.”
“There are thousands of products available to you and it is nice to know when you can trust your selection to do exactly what it says it will. Product manufacturers and suppliers can assist greatly with this by providing warranties, certificates and independent third-party certification,” he says.
THE SCIENCE BEHIND INSULATION
There are three ways in which heat is transferred; radiation, convection and conduction. And all materials allow heat to pass through them, explains Chris Iape, project lead, Sustainable Buildings for Sustainability Victoria.
Insulation materials, however, reduce the amount of heat that can flow through a wall, floor or ceiling by providing resistance to one of the three modes of heat transfer.
Iape says insulation is a “critical component” in commercial buildings in a similar way to residential housing projects.
“Thermal insulation can reduce the air conditioning loads in the space significantly,” Iape says. “This has a range of benefits including lower energy expenditure, reduced plant duty cycle, reduced peak load and potentially reducing costs by downsizing plant equipment at the end of life.”
“Projects we have observed have demonstrated significant thermal performance advantages of insulation improvements in the order of seven percent energy reduction, and three percent reduction in peak cooling load.”
BULK VERSUS REFLECTIVE INSULATION
Insulation products come in two main categories — bulk and reflective — which are sometimes combined into a composite material. The difference between the two? Bulk insulation prevents the transfer of heat through conduction and convection, and is a popular choice for ceilings and walls.
Reflective Insulation, on the other hand, takes on a number of different forms. It is available in sheets backed by foil and works by protecting buildings from heat produced by radiation and bouncing the heat back.
Dr Oscar Archer, a scientific coordinator at Ametalin said that there are many examples of bespoke architecture with dramatically low energy demand thanks to maximised thermal insulation combined with high-efficiency glazing.
“More commonly this is a balance against cost and physical thickness of walls and other parts of the building,” Archer says.
“On the other hand, simple retrofitting or ceiling insulation can deliver immediate efficiency improvements for homes and other dwellings.”
Archer says, “The heating and cooling of buildings account for 40 percent of energy consumed in the built environment. This potentially plays a substantial role in national and international targets for energy efficiency and greenhouse gas reduction, depending on how effectively we insulate our new and existing buildings.”
According to Archer, there was a “significant” level of confusion in the construction industry around the role and necessity of building wraps as components of well-insulated buildings.
“A correctly-chosen reflective insulation wrap can maximise R-values and energy efficiency while managing moisture-related risks and guarding against fire hazards while being convenient to install and expected to last for decades.”
Wall wraps can also minimise the building’s carbon footprint, reduce condensation risk and deliver passive fire protection. A popular line designed by Ametalin is the Thermalbreak 7, which is a closed cell form building membrane which offers an extra R 0.2 for walls and roofs.
“This provides a thermal break in steel frame construction which would otherwise suffer from thermal bridging of the metal structure,” Archer says.
“The 97 percent reflective face delivers an enhanced R-value when combined with an unventilated air cavity, and clever design, can be used on both sides.”
ACOUSTIC INSULATION
While insulation can keep the occupants of commercial properties warm in the winter and cool in the summer, the right kind of insulation can also improve the sound clarity within a room, Pyrotek’s Kris Stasi says.
“These absorbers can either be visible within the room or as standard insulation between wall cavities for the added purpose of thermal protection,” Stasi says.
To reduce the transmission of sound in a room, Stasi recommends a set system constructed from a variety of materials to achieve optimal noise reduction coefficient (NRC) and weighted sound reduction (RW).
“Though a high degree of transmission loss is usually achieved using solid, heavy components which hinder the propagation of sound known as ‘sound bars’, sound absorbers and sound barriers are tested to two completely different methods and thus are two completely different types of materials.”
He says it was important that building specifiers understand the type of environment they are working with and consider what the room is going to be used for before choosing materials.
“Choosing the right combination of acoustic products varies when trying to increase speech intelligibility, lower sound levels, reduce sound disturbances or if you want to create some form of reverberance.”
In open offices, sound disturbance presents the biggest acoustic challenge,
Stasi says, while in schools enhanced speech intelligibility and sound level reduction should be prioritised.