Commercial Metal Roofs

E-therm has been designed especially for commercial and industrial roof systems. Its thin, lightweight design makes E-therm one of the easiest insulation products to install. With its innovative foil flap, E-therm eliminates taping and overlapping on the longitudinal side of the roll. What this also eliminates is loss in square metres per roll when installed. This saves money by removing the cost of extra material while also eliminating the bowing effect that can be caused by overlapping. The 8mm product meets the thermal break requirements that are now mandatory in most of these types of applications. In addition, E-therm in systems also meets the J section requirement set by the BCA.


E-therm comes in different widths and thicknesses to meet your building needs. E-therm also incorporates a 150mm foil flap on the longitudinal side of the product that can eliminate taping or overlapping in most building applications. This saves time and money during installation and provides a vapour barrier that doesn’t rely on tape for it to work.

  1. Roll and lay E-therm insulation perpendicular to the purlins ensuring a minimum of 100mm overhang into the guttering.
  2. Allow a nominal sag between the purlins, naturally this will be around 20-40mm.
  3. Make sure that the E-therm insulation is butted tightly longitudinally and the 150mm foil flap overlap is installed on the top of the product to eliminate water penetration.
  4. All end joins should be taped or overlapped, the tape used should be supplied by Thermotec and have a minimum thickness of 72mm.
  5. Fix roof sheeting by screwing through the E-therm insulation to the metal purlins as per normal.


Thermal Performance Table 
Product Required Air Space Roof Pitch Summer Value Winter Value Design Drawing
E-therm 8mm AG – Ceiling 20-40mm Nominal 5° Pitch R 3.3 R 1.5 DD005
E-therm 8mm AG – No Ceiling 20-40mm Nominal 5° Pitch R 2.0 R 1.0 DD006
E-therm 5mm AG – Ceiling 20-40mm Nominal 5° Pitch R 3.2 R 1.4 DD005
E-therm 5mm AG  – No Ceiling 20-40mm Nominal 5° Pitch R 1.9 R 0.9 DD006