Retaining wall advice

I’m guessing this is a boundary wall and not actually retaining any ground? If it’s retaining ground single block on edge is certainly not enough even with pillars. If it’s just a boundary wall not retaining at 1.8 heigh is go for 140mm block wall with a few pillars. Edit : the answer is impossible to tell without actually seeing the amount of ground this wall will be holding back it. If it’s holding back say 1.5 meter depth of ground then you will need a a very wide wall. If it’s holding back say 600mm of ground you will get away with 9” below ground then onto 6” above.

You could do a block flat with a course of brick infront of it or another solution is brick block brick 3 skins just all depends on how much ground your holding back

Anything over 1m retaining, I would highly reccomend getting a structural engineer, he will know best, and if anything was to fail, the customer and contractor are covered. Also make sure there is sufficient weep holes installed, if retaining, so water can’t build up behind wall

Flat block behind face brick should be ok

Hi there , personally I wouldn’t be paying an engineer to design me a standard retaining wall. At around £300 minimum. He’s a failsafe way to build it ! Concrete your footing .lay a course of 440x225 concrete hollow blocks ( lay them so the short end of the block is on the front of the wall ) once you have laid that course you then drill 12 mm bars directly into the foundation through the holes in the blocks ,these bars need to be around 1200mm long . Then lay 3 more course of those hollow blocks and then fill the holes with the bar in the middle full of concrete. The remainder of the wall is then built 225mm wide off those blocks . It sounds long winded but it really is quite simple, but full proof .

Hi you mentioned the height being 1.8 mt, a lot depends on the load that will be imposed on the "retaining element" of the wall, even if the backfill were to be 900mm behind the wall then I would definitely seek advice from a structural engineer as this will be a expensive wall by the sounds of it and a structural failure at a later date would be even more expensive, take the advice, john