In short: A girder truss carries other trusses. Where it is not supported the way the engineering requires, a large part of the roof is being carried by something that was not designed for it.
The girder truss is not an ordinary truss
It collects load from the trusses that frame into it, which means its support is carrying a concentrated load rather than a distributed one. We have recorded a girder truss not supported where the engineering requires on a Rockbank build. It is the single highest-consequence frame item we find.
Strap bracing that was never tensioned
Metal strap bracing installed but not tensioned is present, visible and contributing nothing. Tension is the mechanism. Without it the strap is decoration, and it photographs as complete.
Top plate to stud anchors
Missing where the engineer prescribed them. Another link in the chain from roof to slab, another item that costs a few dollars at frame stage.
And below the frame
Vapour barrier not extended beneath the whole slab, and bars missed to loadbearing ribs beyond the prescribed span. Across Accolade, Arcadia, Atlas and the surrounding City of Melton releases, the pattern is consistent enough that we check these specifically.
Written by our local inspection team from work carried out in Rockbank. Licensed building practitioners.
