Passive House Certified System

Passive 350 features a 300mm twin wall system with a membrane on the inside forming the airtight layer. The build-up features a 140mm cellulose-insulated stud, a 53mm thermal break, and a second 89mm insulated stud which is designed to be thermal bridge free.

Passive 350 achieves a U-value of 0.13, but this can be increased or reduced by altering the dimensions of the thermal break.

To get this certification, we had to ensure that everything including materials, detail design and factory quality control standards were to the highest level. Four key factors had to be addressed:

  • U-values,
  • Artightness,
  • Thermal bridging, and
  • Interior surface temperatures.


  • In-house certified Passivhaus designers and experienced directly employed installers
  • Successfully completed a wide range of large Passivhaus projects
  • We can design a Passivhaus wall system tailored to suit your project’s needs
  • Ongoing focus on Passivhaus product development