Hello we are currently doing our living room, it is back to plaster no skirting etc.. our current radiator has pipes on show down the wall and along the skirting. but we'd like to chase them into the wall and change the radiator roughly for a similar size. Should we chase them in exactly how they run along the all I.e vertical then horizontal? Do they need insulating they are plastic pipes? As we haven't got a new radiator we're do the pipes stick out of the wall if that makes sense?