Structural calculation

We are knocking out a wall and we need some calculations for building inspector. The total length of the opening will be 148.5cm. On the attachment you will see we are moving a staircase backwards and creating a larger entrance at the bottom of the stairs.

In addition we will have to knock out a small area to give sufficient head height at the start of the stairs so we will be removing a bit of the 1st floor above the start of the stairs.

We are based 6 miles from junction 11 of M25 if you need to visit.

Thanks

Jason