Foamular extruded polystyrene from Austech External Building Products is
being recommended as an effective insulation solution for green roof gardens.
An increasingly popular roofing option for concrete roofs, with many
modern cities demanding a percentage of total roof space to be green, a green
roof is a roof surface, flat or pitched, planted partially or completely with
vegetation using a growing medium over a waterproof membrane.
Green roof gardens deliver several benefits to the home including
increasing thermal mass and improving insulation; creating more stable
temperatures in the building below; reducing energy demands for artificial
heating and cooling; minimising noise; enhancing productive garden space and
biodiversity; providing beautiful views; reducing rainwater runoff that ends up
in stormwater systems; and improving air quality.
However, green garden roofs provide very low insulation from the soil
and plants, especially when wet, necessitating additional insulation to be
installed to achieve adequate R-values.
Foamular extruded polystyrene, a closed cell board with minimal water
absorption and high R-values, is placed below the soil but above the concrete
roof, creating a continuous thermal barrier.
The high compressive strength of the extruded polystyrene ensures the
board is not affected by continuous pressure from foot traffic, growing medium
or other loads, allowing pavers and ballast to be placed on it to provide for walkways
and recreation areas within the roof garden.
Foamular extruded polystyrene offers no nutritional value to plants,
animals or bacteria, eliminating degradation. With its very low water absorption
potential, it can easily function even when exposed to moist growing medium and
Austech offers Foamular extruded polystyrene in a range of compressive
strengths to deal with heavy loads including vehicular traffic.