Retrospective building regs by: Stuart - Highrooms Ltd
Talk to your local authority building inspector about this, it's free to talk and they may even pay a visit to you too.
A retrospective application does cost but is usually based on square meterage, if I recall correctly from the last job that I worked for customer.
You will need to decide when the original conversion was carried out and this will be agreed with the building inspector also as the date decided will dictate the regulation requirements at that time.
It is those regulations that will need to be complied with, unless you personally wish to bring it fully up to date and compliant with current reg's.
In either case, structural calculations will be required to prove that all of the structural work previously done (floor joists, rafter reinforcement, structural / supporting steelwork etc.) is actually the correct size for the conversion created.
You will have to expose some of the insulation too to confirm the thermal values as this will also need to be in accordance with requirements at the time of build.
If it was built that long ago then it may be worth considering upgrading the insulation thickness throughout as well as fitting vent tiles to the roof to maximise ventilation behind the insulation to minimise any potential moisture / damp issues too. Hopefully this helps a little.
Stu
Answer from our expert by: Martin Holmes
Hello Martin,
Get in touch with your local council and ask them what will be needed. They will give you a straight answer and advise you properly on safety issues etc.