Christian McArdle wrote:
Can the lighter 6kg airated breeze blocks be used for:

1. foundations

Usually, but check the specific product for suitability. Celcon Foundation
or similar is recommended for this application, but many standard blocks
should also suffice. However, a wide block like the Celcon Foundation
seriously reduces the amount of labour required, as you can lay the entire
thickness of foundation in a single course and only split into cavities
above the DPC level.

I always thought you had to use engineering bricks in foundations (I'm
not disputing what you say, just never heard of Celcon Foundation!)

David