Procalc’s range assumes windows are double glazed with timber, aluminium or PVC frames.
You should measure the m2 of the actual windows.
Openings for full height glazing should be counted as structural wall lengths
Single or triple glazing plus steel frames should be managed using extras/ps allowances.
For single glazing, deduct $300/m2 (of glass) in Extras/PS Items by inserting the equivalent of Window(m2) x -$300. That is, place a negative sign before the total to deduct
Window furnishings are included in ProCalc’s pricing. Their value is managed by client design source.