Triple Garage with accommodation over query

[Deejay_2]

History

• Original plan was to demolish 1970 bungalow and rebuild with house  incorporationg triple garage with granny flat over.  

Current Situation

• For various reasons we have decided to split proposal into 2 separate applications, starting with triple garage with granny flat over at the bottom of the garden.
• Refurb or reconstruction of bungalow to be considered at a later date.

Question

• More and more I am seeing applications for detached garden buildings/garages with rooms at first floor but classing room as hobby room, studio etc. One I saw yesterday down the road from us in the process of construction looked like a bungalow at the bottom of the garden, with a double garage and sunroom, albeit single storey.  It has wc and shower and one half was labelled sunroom.
• Our current plans show a full scale granny flat with internal staircase, bathroom, kitchen and bedroom.  The building is 12 m x 7 m x 7m (height).  
• Are we going about this submission in the wrong way.  Should we label the first floor accommodation differently ie say it's a hobby room with wc and shower just to help get permission and then could we get change of use somehow at a later date. 

Intention

• The intention has always been to provide accommodation for my twilight years and this is what we are going for with the granny flat.  However, if there is an easier way of obtaining planning permission then it would be worth considering, but only if we could then apply for change of use at a later date. We are in a Conservation Area and also facing a Listed Building.

Has anyone else been in this situation and what was the outcome?