Last year we had lean-to style conservatory built onto the back of our terraced property.

It Measures 15m by 9m

the 2 outside walls are brick built and plastered.
the rest pvc glazed
The opening was not altered, and it has separate doors leading into a through lounge diner.

We are selling and have been told (not by the builder) that we should have had building regs or some type of planning permission for the work.

We had taken no advice and have been rather green..

What should we do first ?

And what is the worst that could happen ?

Do we have a case to go back to the builder ?

Reading the other posts it doesnt look good....