Reaching max height: bricks or cut aerated block?

[nordita]

I'm about to reach my outbuilding's max height but another course of block would make it too tall when I come to doing the flat roof.

Possible options

a) 2 courses of brick then roof

or

b) 1 course of aerated block, cut short via reciprocating saw (around 30 units?). They sit on medium density block.

Another option would be tinkering with the roof height but I don't think I can get it smaller than 140-165mm (10mm mortar + 22 or 47mm wall plate + 100mm joist + 18mm OSB). Not sure what's standard height for a garden room?

Cutting the block seems quicker but I may be wrong. They would achieve the height at half the price of bricks. I'm aware they need a weaker joint mix, suck moisture and are trickier to render (maybe I'd clad them as a visual accent).

Any problems with choosing option b?

 

[George_engineer]

Your merchant may well have coursing concrete 'bricks'. Easier and healthier than cutting the blocks.

However yes you could cut the blocks and that is better than mixing with clay bricks.

 

[^woody^]

Just cut them down with a wood saw. You could have cut three in the time it took to write that post!

 

[phatboy]

Can you not get 'chocolate bars' - blocks that are 4" x 6" or thereabouts. Or concrete bricks, depending on the size you need.

As woody says, an old saw can cut aircrete, or go posh and get a block saw for them, it goes faster and lasts better.

 

[noseall]

Can you not get 'chocolate bars' - blocks that are 4" x 6" or thereabouts. Or concrete bricks, depending on the size you need.

You can get concrete commons or lightweight coursing bricks (internal/thermal). We use whatever is the most efficient cutting wise. A block cut straight in half (along the length) bonus, or if the last third can still be used, cut 140mm pieces. Otherwise we just go for the lightweight coursing bricks.