Securing a landing on two walls????

[Iwhanmer]

Hi,

I am planning to fit a new staircase from my landing up into a loft conversion.
The problem I am having is the new staircase has a half-turn with a landing but only two walls to support the landing one to the left and one to the rear, the right is open.

Can anyone help me with how to secure this landing in a way that will keep the building inspector happy?

 

[pinenot]

Ask the building inspector, they are now there to help as well as certificate...pinenot