There is a bit of confusion about walls and what constitutes a ‘structural change’ and what constitutes a ‘non structural’ change or a ‘reconfiguration’. Knowing the difference between the two means that one is probably a Minor Renovation and the other is a Major Renovation. As we all know, approvals for both are quite different.
Here is an extract from Partridge, (a multi-disciplinary engineering consultancy in St Leonards, Sydney), when asked the question about a servery window in a kitchen:
Generally speaking, in multi-storey or strata situations, the engineer’s main focus is “Will the removal of this wall impact the structure and the neighbour above?”. If, in your example, the servery wall is non-loadbearing (i.e. it doesn’t support the floor above), then simply increasing the size of the servery window would be a non-structural change. Yes, the servery window might now need a new or larger lintel above it, but that’s a simple internal matter of just holding up the brickwork above the window. The sizing, configuration, and fire-rating of the lintel has no impact or influence on the floor and neighbour above, so we would deem it a non-structural change.