This Wales Online article relates to an unauthorised home of some 30 years.
In other words the homeowner did not apply for planning permission or building regulations consent.
The local authority can and will take enforcement action against homeowners in breach.
They can order you to tear down any unauthorised extension or buildings.
They can be awarded injunctions and the Court is likely to ask you to meet all costs as you breached planning and building regs legislation.
Don't build it and hope for the best!!
Ignorance is no defence.
The information is available online.
It's NOT our builder's / installer's responsibility to obtain planning and building regulations consent. It is the homeowner's responsibility.
Read full Wales Online article here …
This article evidences yet again that the council will take action. It is not worth the risk!