I'm planning on building a timber walkway around the house, 60cm wide under the eves and the inside joists bolted to the concrete house foundation. The house was built less than 2 years ago with no landscaping done, and so there is a 50cm thick layer of compacted metal wide enough to build the walkway on. The walkway is only around the back of the house for access to my shed, not for general use.
For the middle and outside joists, do I still need to drill holes and concrete in posts or will it be fine laying the joists with packers on top of the metal? Or use old stepping stones as footings?