tieing the inside wall to the outside wall

[amazondean]

I am having a small extension built at the back of my house. I am using imperial bricks (75mm) but metric blocks for the inside. This means that as the wall is being built the inside is going to be lower that the outside. My question is when the inside wall is tied to the outside wall the ties will be pointing downwards and towards the inside istead of straight across causing possible damp issues. Can any one tell me what the answer is please.