01
Common limits
Welsh Government guidance says equipment should not protrude more than 200 mm beyond the roof plane or be higher than the highest roof point, and it should minimise effect on the building and area.
02
Situations needing care
Flat roofs, listed buildings, scheduled monuments, conservation areas and installations on walls facing a highway can introduce different limits or consent requirements.
03
Ask the authority when unsure
Use the official guidance, then confirm ambiguous property circumstances with the local planning authority before work is committed.