Retaining wall. To DIY or not?

22 Sep 2018
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United Kingdom
Hi all,

I want a retaining wall in my front garden and want a little advice before I decide if I’ll be the one tackle the task.
I’d normally give this sort of thing a go but because of the length of it I’m questioning it.

So, my garden is almost flat and then all the way along 1 edge it banks up. The top of the bank is almost level and is about 1.5m wide to a fence. The earth hasn’t moved in the 3 years I’ve owned the property.
I want to build a 900mm high wall. Placed half way up the bank and then backfill, to create a flat surface to be shingled with a few potted plants and also a flat lawn.
the wall will be built with blocks and then rendered (By a plasterer).

The wall will travel 12m straight. Then angle approx 110 degrees and run another 5M.

I have read a lot about this type of wall and have been advised it is fairly straightforward.

my questions are...

Is a wall of this length and not a straight forward angle, a bit over ambitious for a newbie? Or, is it case of a 1m is just as easy as a 12m wall?

Is the 7n dense concrete block the block I need to be using?

how long would the average pro take to build this wall?

Thanks in advance for any help.
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Do you intend to build using a single skin of concrete blocks?

What about drainage?

Have you considered you will need a foundation?
Yes, it will be a single skin, largest face of the block downwards.
The foundation will be done by my brother (ex ground worker).

I intend on installing weep holes and a gravel back fill.

My main concern is that as a novice on a wall of that length it will be like a leaning banana. But having never done it, I’m not sure if I’m worrying about nothing.
Get yourself a decent spirit level , use a line and you will be fine

1st row of blocks is the most important as if thats not straight the rest of the wall won't be either

As you're rendering it doesn't have to be perfect

Have fun!
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Draw a picture or something, I've not got a scooby what you plan to do.

But the thing is with walls 'halfway up a bank' is that they need foundations deeper than the bottom if the bank, if you don't want then sliding down the bank. And a 100mm block wall won't cut it.

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