Ledger for raised decking

[numpty1979]

I am currently planning on building a raised deck attached to the house on one side using a ledger bolted directly to the wall. On the opposite side I will run a beam stood on the "legs" and between the two run the joists. The whole thing will be quite small - pretty much 2.4m by 2.4m and the deck itself will only be about 12 inches off the ground.

My question is what thickness should the ledger and beam be in order to safely support the deck?

Gratefulf or any suggestions.

[numpty1979]

Nobody know?