Deck Ledger and Termite Inspection...

I'm after some advise on deck ledgers and termite inspections please.

We're building a new home and the builder has used the glass granule type termite protection as a layer in the brick veneer (two bricks up from the slab).

We want to attach a deck to the back of the house.

How much room do we need to leave under this layer of glass granules to the top of the deck (for visual inspection)? Is there any way we can go over this layer with the top of the deck? Unfortunately the patio is higher than this layer of termite protection and I'd like to deck this as well without having a step down the rest of the deck.

While I'm on the topic - I have some F17 150x50 I was going to use as the ledger - it is unseasoned and untreated - can I use this and what will the gap between this and the ground have to be.

(I'm in Qld if it makes a difference)

Thanks
Grant

You can go up to 50mm below the Inspection Line from the top of the deck board if you have Termiglass.
If you want it to go higher than that, then you will need a termite barrier like Kordon to be installed, contact a local pest guy to do it for you, the ledger then bolts over that layer of barrier to the wall.
You are crazy if you use that timber, unless you want to invite the little buggers in!