DHope

Hi, I bought a 1950's bungalow with a large 'attic storage room' that looks like it was part of the original build judging by the roof structure with a dormer (see attached photo), 6 inch joists in place and has been boarded with electrics. The only confusing bit is that there is a ladder rather than stairs, so the estate agents classed it as a storage room (the previous occupant was elderly and obviously didnt use the room - they've passed away so I'm not able to ask them about it). I'm a little confused what I can and can't use the room for now though. It obviously doesn't meet current regs with thermal insulation requirements (zero insulation), fire protection etc, but guessing it was fine when built. I've checked the local guide on access and a fixed ladder does actually meet the requirements 'where space is restricted and doesn't allow for a staircase' as is the case. I'm currently using it as an office while working from home but worried about my insurance. Do I just treat the room as a habitable space as it's been there since it was built (and inform my insurance that I'm using it as a room), or do I contact building regs for clarification and potentially open up a can of worms?! Any advice/opinions would be welcome, thanks