Home Owner Warranty Insurance Coverage - Common Property Lot

We own a torrens title townhouse that is within a community scheme, for the common property that consists of some Gardens, Drive Way, Street Lights, Fire Hydrants & a Letter Box Unit.

We have now had two leaks from the fire hydrants, both have eventually been fixed with a combination of the association paying a plumber to look at ? then been past back to the builder when shown to be a defect. We have a total of 5 hydrants and there is a belief that they all have the same defect that has led to the first two leaking, so we are in the process of trying to get the builder to accept this and fix then all.

Because of these issues we have been looking into the Home Building Warranty for the property, as there is some concern that the builder may go belly up before he completes the work to fix the hydrants (this is not helped by the fact that the original plumber is no longer in business).

We have got copies of the Home Warranty Certificates, however there are only certificates for the individual torrens title units. Should we have a certificate for the community lot? The insurer in this case is Vero. We are concerned that the appropriate insurance was not taken out by the builder at the time of construction and where does this leave us if there is not a policy for the community lot.

Stats: Total of 28 Lots; 1 Common property; 27 Units
Interesting question - the Home Owners Warranty is generally for the individual properties. What is the requirement for common areas?