Glass margins

This is kind of hypothetical question. If in 3-5 years time vrx decide to build a glass plant what will be the margins on our silica. If 1 square metre of 4mm glass is 10 kilos at say $175 per square metre to end customer. My mate is having glass installed on his deck and is costing thousands. Does anyone know what the asic is for making glass per square metre or tonne roughly. I dare say a lot of govt projects would prefer Australian made glass. The margins in this could be next level for vrx I realise they won't be selling for $175 per square metre(10 kilos) but there's a lot of room in there.