Here are a number of CAD drawings showing the basic plans.
This is a small house from 1948 with a single bathroom and two bedrooms in the upper floor. The lower floor has a laundry room and an office.
The extension will allow us to put another bathroom upstairs and expand the master bedroom. Downstairs will have a new guest/work room. We can’t put a bathroom downstairs because it is below street level, so the plumbing would get expensive.
The deck will get a half-width 10′ extension, so we don’t lose our sunset views. It can’t be full width because of the steps and a large eucalyptus tree.