STEPHEN MACKENZIE, FIRE SAFETY CONSULTANT

Generally you treat a roofing insulation as a comparable risk to that of cladding.

But if you get an ignition source with combustible material, which depending on the roof construction will always be a risk with hot works, any mechanical plant and equipment, or even a lightning strike on the building, the whole thing will just go up.

Once it gets going we have a Glasgow School of Art or Grenfell-type scenario.

I would suggest a complete ban of foam and combustible insulation throughout construction unless the fire risk can be mitigated by fire suppression or other control measures.

In my mind it would really raise public safety.

China has banned combustible insulation on new buildings due to fire hazards.

Although the V&A uses a safer hot air welder, there is still hot work and other fire risks.

Another known issue is paper lanterns that have touch paper as heat generation for lift.

They can carry for miles but if they land on something combustible they could set the lot off.

There are limited benefits in cost of using the type of insulation that is in the V&A.

Yet we have a comparable stone wool product which is less combustible, more inert and potentially has comparable thermal performance.

With the ban on combustible materials announced by UK Housing Secretary James Brokenshire, England is now in a position to comply with the intent of the building regulations to limit external fire spread in key occupancies, such as sleeping accommodation or high dependency buildings.

The ban must also address the issues with expanded polystyrene rendering or high pressure laminate cladding systems, however. Only stone wool insulation should be used.

The fire hazards of foam insulation below 18m and in other occupancies must also be reviewed, with limits or prohibitions put in place to ensure fire risk is treated at source.