forster thermfix vario Hi offers excellent heat insulation at passive-house level in the phA class. Impressive dimensions are possible with a steel profile system such as the forster thermfix vario Hi . The certified [...] windows and doors. System variants: forster thermfix vario Hi for highly insulated curtain walls without safety requirements forster thermfix vario facade for safety applications and sloped glazings - [...] this profile system is based on the standard mullion and transome constructionfrom forster thermfix vario, many components can be used system-wide. This guarantees an identical appearance of the facade,