Toothed in Brick work

If the wall is extending flush in the same plane then it should be toothed. If it's butting up at 90 degrees to the original then butt joint with wall starters.

 

Not really ok unless the cavity has been maintained by cutting vertically either a 50mm gap or a blades width with a vertical dpc fitted.

 

I did this with a 9" brick wall - think original 'L shaped' section that became a 'T' shaped section. The exterior bricks were toothed and the block work butted.

 

I would add that if you are going to do this make sure the builder knows your wishes, as standard modern bricks are slightly smaller than those used a few years ago, and he'll have to order accordingly.
All depends on age of house.

 

Worked on an extension a few years ago, house built in imperial bricks. Managed to get imperial brics for the ext but the blockwork inside had to be metric. Brick ties were hard to do with the difference in levels as it went up. Something to watch out for.

 

We always used to tooth in brickwork as said. I have however heard that it is now frowned upon due to the chance of uneven settlement in new foundations, causing bricks at tie in to crack.(Before you start shouting, it what I heard, lol). Also brickwork can run a max of 12 metres without an expansion joint, does the overall exceed this? Just use a tie in kit and expansion joint mastic.
Some companies still make bricks to imperial sizes also.