I need building control drawings and structural calculations

I need building control drawings and structural calculations for our self-build renovation project, passing it through LABC inspectors.

We are renovating our 100-year-old stone building (450mm solid granite walls).
We have been removing all the damp and damaged walls and floors to assess what we have and what needs attention. The building is now nearly stripped back to stone walls, joists and roof trusses.
We will be able to review the trusses when we have scaffolding and are able to remove the existing damaged soffits and fascias.

We intend to have reverse plan living with a vaulted ceiling. It is a semi detached 2-story property with an existing 3m x 5m extension to the rear; the extension includes a basement, ground floor room, and 1st floor balcony.
Postcode: TR109HR

The total floor space of the property covers 123m2 (includes the basement and balcony), covering the rectangular building shape.
Length: 14m (11m without extension)
Width: 5m
Height from floor to eaves varies from 8m to 9.5m (sloping drive).
It has a cross hipped roof varying in height from the eaves to ridge between 1.5m and 2m.

We have nearly completed floor plans, drawn to scale, for the two floors (but not the basement).
We have created these plans using A2 sized cardboard for each floor, then added coloured card to represent various components in each room (toilets, shower, beds, cooker, sofas, partition walls, etc.).
We have not done any plumbing or electrical drawings yet.

We believe our renovation requires structural calculations for the following elements:

Restructure all joists to meet building regulations.
Current specs of joists:
First floor: currently has 24 joists @ 170 x 50mm, spanning 4.4m with 460 centres). All joists are subject to wet rot at one end/south facing side.
Extension: Replace ground floor/cellar ceiling joists (currently 13 @ 150 x 47, spanning 2.7m with 400 centres)
Extension: Replace flat roof balcony with new joists (currently 13 joists @ 110 x 47mm, spanning 2.7m with 400 centres). Then replace the roof to incorporate an EPDM low pitched roof with a flat composite deck type floor above this.

Remove existing stairs and reposition them.
Add two roof windows.
Review hip structure at one end (from potentially overzealous carpenter).
Replace existing cracked concrete reinforced lintel spanning a large window.
Remove existing 1st floor patio door and increase length of opening.

Other components of the renovation not requiring structural calculations include:
Replace existing pitched slate roof like for like.
Replace soffits, fascias and gutters (UPVC).
IWI using wood fibre board onto internal lime plastered wall on all externally facing walls (and party wall).
Roof: warm roof, 150mm PIR insulation with Roofshield breathable membrane.
Ground floor: remove combined suspended floor and concrete floor and replace with glasscrete or limecrete floor.
Repointing all external walls and changing all windows to double and acoustic glazing UPVC.
Converting the existing front door to a window (by decreasing the height and blocking the bottom aspect; the existing width and length dimensions remain the same).
Converting an existing window into a doorway (by increasing the height; opening up the lower section of wall under the window; the existing width and length remain the same).
Partition walls for acoustic insulation and structural purpose where required.
Toilet upstairs (position yet to be determined).
Reposition and upgrade consumer unit.

I have included the maximum amount of attachments permitted (3).
These are the ground floor and first floor plans which are to scale, but not completed. I've also attached a photo of the south facing side aspect of our house that shows the extension.

Our budget is modest but appreciate the amount of work involved.

Many thanks in advance,
Damian