No building regs for new roof

[Calloutthelies]

I am a tenant in a property that had a roof replaced due to leaks. 
the landlord got some two bit company to do the work and didn’t get any building regs. 
the property is freezing and would have thought they’d have to upgrade their insulation whilst doing the new roof…? 
anyway I’ve spoken to building regs officer and they’ve said the landlord has told him he’s only replaced less than 25% of the roof therefore no building regs required. 
apparently supplied pictures and schedule of works. But this schedule would have been of the patch repair he did before deciding to replace the whole roof. The pics and company he used would have provided would have different dates. 
he said unless the work is in progress there is nothing he can do. 

What is the point in building regs if they don’t even check properly. 

[BankFodder]

How long have you been living at the property. How will you get on with the landlord and does it worry you to fall out with the landlord at a fairly catastrophic level?

[Calloutthelies]

No I’m not bothered about the relationship with the landlord. 
He’s been bad from day one and I believe in karma