Enlarging existing loft hatch to install new hatch and ladder. Is my thinking right?

[muthafunky]

Hi all.

Will what I'm thinking of doing be OK?

I need to open upy existing loft hatch to fit a new hatch and ladder before I board my loft out.

My pre-existing hatch is roughly 600x600mm and sits inside a frame where 2 joists (blue on the edited photo) have been cut and sistered (green) before I had the house.

My thinking is to open up the as per the red box in the edited photo that will give me an opening of approx 650x950mm. I could possible lengthen this by around 100mm towards the joist closest to my in the picture but I can't go any further due to the wall below.

If I were to add 2 additional 4x2 trimmers (yellow) this would give me roughly 550mm opening width which I think is an available loft hatch/ladder size.

Does this seem feasible?

Additionally, could I get away with a single additional trimmer on the left side to give me the potential for a 600mm loft hatch/ladder?

Any help is greatly appreciated.

 

[Wayners]

You could get rid of yellow and put in blue.
Loft hatch would be wider and the frame could be tight to wall.

Whatever you think is best. Not saying my plan is better