Garage Door

[adiwllow]

Hi all, hoping to have finally found the place to answer my question :)

I have a garage which is part of the house (IE under other rooms) . I want to insulate the single skin metal door, as it gets extremely cold in there and we use it regularly.  So, a couple of questions if anyone can help:

1) Does this garage door insulation actually need to be fireproof if there is already a fire door between the garage and the house?
2) Assuming it does, does anyone know of any cost effective Class 0 or class 1 insulation which would be suitable?

The only thing i've seen which fits the bill is superfoil SNFC, but it only comes in 8M rolls , might be too thick, and has a high cost. 

Thanks :) 

[adiwllow]

anyone any ideas? Thinking of now using superoil SF19FR which is Class 0 and and class 1... adhered to the door.
Would that be okay for fire regs?

 

[AnthonyB]

I'm guessing the metal door is between the garage and the outside? If so use what you want.