When we measure a window for a new piece of art glass, be it traditional leadlight, SGO modern stained glass, or sandblast there are common measurements required.
For the initial quotation and art work just an approximate size is ok, usually the daylight measurement on the sketch below is sufficient.
From the sketch above you can see that from the two measurements, daylight and tight we then produce the glass size depending on whether this is going into an aluminium frame or timber frame as above. We record glass sizes as the vertical first followed by the horizontal. Another consideration to consider is whether the art glass is to be included in a Double Glazed Unit (DGU). This information is also critical as depending on the final median the art glass can either be included as one of the faces of the DGU or in the case of traditional leadlight inserted inside the DGU.