Which blocks are best?

[rustically]

Constructing a bungalow and the walls will be those cheap grey blocks with concrete rendering
I am probably going to put UPVC windows and doors in and wonder whether these blocks will make a strong enough wall to support these items or whether I should buy something better ,as always giood advice would be much appreciated

[Norton]

those cheap grey blocks

The concrete ones?

[sabang]

Superblock / Q con costs more than brick, but I think the better insulation properties make it well worthwhile.

[nevets]

Small bricks are better than blocks , less cracks in the wall.