Solid Wall to Cavity Connection

[DTB1985]

HI all,

So just wanted to make sure I'm not missing something with this.

We are having a new extension, its walls are a single course block wall with external insulation and render. This is fine and I'm happy with it but where the single course block meets the existing property which is cavity wall I'm struggling a little to figure out how they will interface.

As it stands my best guess is to cut a channel into the outer course of blocks on the cavity to create a gap and cut a corresponding slot into the blocks of the extension and insert a vertical DPC to aid in weather proofing. I've attached a plan that shows the vertical DPC as a red line.

Do you think this is on the right track or am I missing something. I appreciate it's not a perfect solution but I honestly cant think of anything better.

If anyone has any pearls of wisdom I'm all ears.

Thanks,

James.

 

[motorbiking]

I can't see the picture, but assuming this is some sort of thin joint construction system or regular block, why wouldn't you use a metal wall starter to connect the new wall to the old wall. It will be waterproofed by the external render and roof.

 

[^woody^]

As its autumn, I'll throw in the old chestnut -"What has your designer specified on the plans? "