converting loft

hi there I am wanting to convert loft but not 100% on best way to do raise joists
i will insert some pics of my drawings

• I can either add joist hangers to the main 3 joists then the add supporting sections or just screw straight threw
• add more main beam lying 90 degrees on ceiling joists then supporting sections

see pics all advise will be greatful

also my roof trusses are 100mm deep I am going to add 50mm kingspan/celotex insulation and leave this flush with joists which will leave the required 50mm gap for air flow.
then I will get the aluminium insulation foil and staple that to the trusses. I need advise from here either the plaster board direct on top of that and screw it threw or to put battens up going left to right across trusses then plasterboard.
do you also think this will be enough to help heat detection from roof

Can Anybody advise

I'm never a big fan of loft grows they are very popular in eastern states and the UK, but growing can involve a lot of water, electricity, and in a loft variable temperatures, it's not difficult to grow in a loft, just be prepared for lots of infuriating variables, like visitors twitching there noses, strange gurgling noises in the ceiling, then there the SWAT chopper hanging 10 feet of your roof at 2 in the morning, if in doubt, rent a FLIR camera at your local home depot, once established
good luck
"V"

Hi im thinking of doing the loft, i asked the carpenter today at work about it, he said in my type of house (old terrace) he would advise just to board over the joists that are up there.
when i asked about the weight of stuff i would be storing in loft,he then said run some new timbers across the top of old timber joists and then board on top of them.

i am still not sure if it would hold to 90l brummie bubblers if you do get any more advice be good to hear from you matey
Kool rocknrolla