which type of blacks to use for garage and garden wall

[daywalker]

Hi I hope you maybe able to help
I am building a garage 6m x7m double skin with tiled pitched roof
not sure which blocks to use 7n concrete or 3.5n two sides of the garage will not be visiable,
wasn't intending to render the garage,

also at the same time building new garden wall single skin in blocks again which blocks would be the best option

thank you for your help :D

[welsh brickie]

I usually use 100mm width single skin solid concrete blocks with piers when building a garage.
Or you can lay them flat giving you a solid 225mm wall.
for the garden wall the 100mm solid concrete is better.