Is it usual to build walls of sufficent accuracy to fit standard sized doors and windows, or build walls as best you can and then measure up and order each separately ? Standard sized french windows, for example, seem to be a lot cheaper. I'm sure the volume housebuilders order loads of identical windows - how do they build to the tolerance of a few millimeters in order to fit these ? Simon.
I think they brick up to the frames
Make a dummy frame the size you want and brick around it. Remove frame and fit the real one. That's how its done by the big builders so they can order cheap standard frames.
You've posed the question backwards; 'Standard' winnows lintels, cills are manufactured to brick (plus mortar gap) and half brick multipiles.
Or whack the frames in using wedges, then shove mortar in the gaps, or mastic, or expanding foam.
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