Cut a level hole for the window
Install a supported Lintel.
Marking out the cut.
A self-levelling laser matched the window height with other windows.
Pilot holes were drilled in the corners.
All of this was done under Permit.
Excavated to the weeping tile's gravel bed.
A vertical drain pipe will sit above the weeping tile.
The fill around the vertical pipe includes a layer of gravel, and a thick landscaping cloth.
Cutting the hole
Lined up with pilot holes and double-checked, the hole's sides are cut out.
A wet saw is used. and when working from the inside, a basin made of tarps keeps the watery sludge contained, which is simply wet-vac'ed away.
If the cuts can extend past the edge of the window space, then a larger coring saw can cut the block out in a single piece.
Sometimes a larger coring tool can not be used.