Hockmore Tower, where Oxford City Council has pledged to remove an HPL rain screen cladding system (Image: BM3 Architecture)
Some cladding systems featuring certain types of high pressure laminate (HPL) panels, particularly when combined with combustible insulation, should be dealt with “immediately”, an expert panel of government advisers has told building owners.
A new advice note issued by the Ministry for Housing, Communities and Local Government (MHCLG) told building owners that its BS8414 test of a cladding system comprising an HPL panel with fire retardant (Class B-s1, d0) together with stone wool insulation achieved the performance criteria and can be considered safe on existing buildings, albeit depending on how it was fitted.
But it warned that HPL panels of a European classification of Class C or D were “very unlikely” to resist the spread of fire adequately. Systems using any type of HPL panels (Class B, C or D) combined with combustible insulation were also very unlikely to resist fire spread, it warned.
“Building owners with these systems should immediately take action in like with Advice Note 14,” it advised. Advice Note 14 was first published in December 2017 and updated in December 2018, and covers external wall systems that do not incorporate Aluminium Composite Material (ACM).
MHCLG’s expert panel added that the level of risk from unsafe HPL systems was still not as high as the risk from unsafe ACM Category 3 panels, with the removal of those systems remaining an “absolute priority” for building owners and operators.
“For the avoidance of doubt, both the removal of ACM Category 3 panels and action to remediate unsafe HPL systems should be carried out as soon as possible,” it added.
For new residential buildings of 18 metres or more, the government has banned the use of combustible materials in external walls. The ban limits materials to products achieving a classification of Class A1 or A2-s1, d0. The expert panel added that it was not aware of any HPL panels, which are typically made from sheets of wood or paper fibre layered with a resin and bonded under heat and pressure, meeting those classifications.
