Polyurethane is a polymer-based construction material. It can include rigid or spray foam and can be used in residential and commercial buildings for insulation.
Polyurethane insulation helps conserve natural resources and helps preserve the environment by reducing energy usage. With its excellent strength-to-weight ratio, insulation properties, durability and versatility, polyurethane is frequently used in building and construction applications [1].
Polyurethanes are formed by reacting a polyol (an alcohol with more than two reactive hydroxyl groups per molecule) with an isocyanate in the presence of suitable catalysts and additives to produce a foam. For insulation foam, methylene diphenyl diisocyanate (MDI) is usually used.
In Australia, our buildings account for 19 per cent of total energy used and 18 per cent of our total direct GHG emissions according to the Australian Energy Update 2017 [2].
Polyurethane insulation is a key part of a sustainable, energy efficient solution because it has a range of advantages over alternative materials for meeting energy efficiency requirements. Polyurethane insulation materials also save more energy during their lifetime than is used in their production.
Polyurethane insulation improves living comfort while generating significant energy savings, thereby improving access to affordable and future-resilient housing and increasing energy efficiency [3]. The initial cost of building energy efficient housing is generally higher due to the extra costs associated with improved insulation. These are short-term costs, which will be returned as the gains from energy savings will be significant [4].
Polyurethane insulation systems create protective air barriers in roofs, walls and under floors, effectively sealing off the building from the elements to help save energy. Furthermore, buildings insulated with polyurethane foam often require smaller heating and air conditioning units, which could save additional money for the building owner [5].
Energy efficient buildings, such as those using polyurethane foam products, use less energy to heat and cool, requiring less fossil fuel use and emitting fewer greenhouse gas emissions [5].
Polyurethane insulation has fire resistant properties and is thinner compared to conventional materials, which leads to lighter construction and more indoor space [6].
Polyurethane spray foam insulation is a highly energy-efficient product and quickly offsets its manufacturing footprint. Compared to other insulation and air sealing products, the environmental payback period for spray foam can be as little as 7 to 8 years. With the typical insulation life span of 75 years, this means that spray foam can save energy for generations [7].
More information on polyurethane insulation is available on the Australian Modern Building Alliance (AMBA) website.