Good question.
Depending on where you are in the world the term bargeboard can be called something else. For us here in the UK the below image shows which part or a roof is called what. For most of the parts there are multiple words. For example, Fascia Board can be called all of the following,
Capping
Cappit
Fascia
Facial
Cap over
Jumbo
Replacement
Full Replacement
Double board
And the list goes on…
Its important to know that there are two main types of fascia board, 9mm capping fascia board and the thicker 18mm replacement fascia board. This would be a trade counters first question if you were to ask for fascia. 9mm capping board is used to fit over the top of sound existing timber fascia boards, it’s L shape will cover the front face and underneath of the old fascia. Replacement fascia is double the thickness and requires the old fascia to be fully removed, exposing the ends of the rafters. The 18mm replacement board is then nailed directly to the ends of the rafters and any corners or joints are now fitted before the guttering is firmly screwed in.
We supply upvc fascia and soffit which can be found here and here all available in the most popular colours, with the above knowledge you can make sure you are buying the correct parts you need.