Plastering over rooflight trim

[Spinny]

Is it feasible to successfully plaster over my roof light trim (see pic) ?

 

When I bought it the manufacturer said yes, just double skim the upstand taking the second skim coat over the white trim.

 

Now my plasterer is suggesting no, because it will crack, the only way would be to double line with a second layer of board over the trim - which would then then reduce the opening by 25-30mm each way.

 

The trim is powder coated metal - not plastic.

[Mr Punter]

Is that a gap between the plasterboard and the trim?  Maybe a zoomed out photo would help, but my feeling would be not to plaster over it or add a second board layer.

[nod]

No it will definitely crack away 

[Spinny]

More photos as requested. This shows the roof light upstand without plasterboard fitted and the edge of the rooflight. The rooflight has a channel in it for plasterboard to slot into and the top of the rooflight, channel, and trim is made of powder coated metal. Once the plasterboard is slotted into the edge there is a proud lip of 2-3mm so it can be plaster skimmed up to flush with the edge of the trim.

 

I was told it can be double plaster skimmed to cover the trim to give a plaster to the glass look and that they routinely had customers that did this.

 

Tape ? Blue Grit ?

 

Have I been lied to ?