Loft Hatch Help

[warco]

One of my customers has asked me to enlarge a loft hatch. The house is 1920`s with an old syle roof (made in situ).
Does the loft door need to be fireproof ? would 10mm MDF be ok ? I dont want it too heavy.
I will need to remove part of one joist , but of course, this has a strut/hanger on it further back into the roof. Will the new 3x1 trimmers be sufficient ?

 

[myboys]

does not need to be fireproof i would personally use 19mm mdf for the lid and 3x2 or 4x2 trimmer depending on existing ceiling

 

[DevilDamo]

It may be worth while providing some insulation to the back of the loft hatch to help prevent heat loss.

 

[^woody^]

No specific fire precautions required unless a three-storey

10mm mdf will bow like Rolf Harris's wobble board