1150mm  minus 100 for insulation minus 65 screed equals 985mm so about 100mm above the kitchen units

Roughly speaking, the existing upstairs bathroom and bedroom5 windows look more than a metre square. Nick thinks maybe 1200 wide apertures.  We cannot get access to the property today because the new slab is still wet.

Nick instead estimated by counting the number of insulation squares beneath each aperture – we think 12ish squares, so maybe 1200 wide.  If that is the case, then good news as this suggests that the new windows can be two-pane.  You’ll have to double click on the photos and try zooming in.