whilst others just want to pick holes in everybody else' helpful suggestions but rarely seem willing to offer any practical solutions themselves
It would make me very sad to think that comment was directed at me Kurnal?
If only every door had the label or the cores......most sadly do not! A pity it wasn't mandatory on all fire doors.
AnthonyB's post
Is actually my point. Along with my original post pointing out the manufacturers of uPVC are claiming it is in itself intrinsically fire resisting. It is not. And one of the qualities that it is claimed make the product self-extinguishing is the liberation of halogens by pyrolysis in the form (usually) of chlorine gas. Not particularly good for the lungs. Allied to this the pyrolysis liberated vapours are potentially extremely flammable.
I did an interesting experiment the other day igniting petrol on an apparent PVC door. It did not burn in the way I would have expected. The door was not marked or sold as fire resisting in any way. But it had an interesting core. Felt very solid to tapping as well.
I did however, examine a PVC replacement front door to a flat that had charred to destruction and assisted in filling the dwelling with HSG which had subsequently ignited (the HSG not the door). The door was onto a common walkway that originally had been a balcony approach but had been modernised by the fitting of uPVC frame glazing to the balcony (enclosing it to a corridor) and replacement uPVC front doors to the flats. The newly formed corridor had filled with nasty HSG and the heat had started to char that PVC as well.