Sigma® OP2

Pre-insulated or open panel solutions


This wall type is ideal for designs where air tightness greater than 3, minimum U-values and thinner wall build ups than Sigma® OP1, are desired.

This system utilises the existing 89mm or 140mm stud options and introduces thermal laminate plasterboard, in combination with a partial fill polyurethane rigid insulation between the studs. U-values ranging from 0.37 – 0.14 can be achieved. Typically this wall solution suits projected 2013 regulations, CSH Level 4, FEES Compliance or Section 7 silver rated homes or walls requiring thinner build ups than Sigma® OP1.

Sigma® OP2 has the following benefits:

  • Improved thermal performance, with a range of insulation thicknesses
  • Utilises plasterboard layer for air tightness delivery
  • Retains 89 or 140mm studs, for manual erection
  • Limits wall thickness and maintains existing foundation
  • Reduces thermal bridging
  • Services accommodated within studwork and space formed in front of the rigid Insulation
  • Utilises conventional skills and materials
  • Option of factory fitted rigid insulation to achieve UKTFA class B fire protection during construction
  • Offers thinner wall build up than Sigma® OP1


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