In article .com,
wrote:
Sounds obvious but eveyone seems to assume you just know.
If you build with strip foundations, what goes between them, i.e.
on the sub-floor. Old days it was just earth, and lots of new
houses are built on a slab, but if using strip foundations, what
covers the sub-floor ?

IME most people seem to prefer deep strip aka trench fill foundations
- i.e the concrete is brought up to 150mm or so of finished ground
level. Topsoil should be removed from the area to be covered by the
floor slab. The walls are built up to dpc/finished floor level and
the floor slab is poured inside them, usually 100mm concrete on a
polythene dpm on sand-blinded hardcore. You can get problems with the
hardcore settling so it should be well compacted in layers of 225mm
max and if the total fill thickness would exceed 600mm the floor
should be suspended - i.e. bearing on the walls. Concrete beam and
block is a favourite in this situation as it is quick and easy to
install and provides a good working platform during construction.

--
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