Another vapour barrier question...

[derekphl]

I've taken the chimney breast out in this ground level room. I'm going to batten the wall and install insulated plasterboard, but not sure if I need a vapour barrier of some sort here?

I'm going to put a ventilation duct on the skirting through to underfloor, whether or not that is relevant to the question. Thanks in advance.

 

[derekphl]

Never mind, I thought that the plasterboard I bought didn't have a built in VB, but it turns out that it does. I had thought that the stuff with a VB was double the price, but I just didn't read the detail.

[Note to self: RTFM]