Small garden retaining wall

[Ian H]

I want to level our lawn which will mean building a small retaining wall.

I was thinking of using 5 dense blocks on their side, putting some pipe through at patio level and backfilling behind it with some gravel.

Does that sound right or should I be wrapping the gravel in a membrane?

Thanks

 

[23vc]

No expert, but strength wise I’m sure that’ll def be fine (done similar in double skin brick and it’s fine, didn’t bother with the drainage pipe either), are you planning on rendering it? If so moisture penetrating from the wet ground behind might be an issue and blow it after a few years

 

[Ian H]

Yes, I was going to curve it a bit then render. I hadn't thought about moisture, I have some thick plastic boards I could line the back with or a load of fibreglass at work.

 

[23vc]

I did the one in pic 3 years ago and it
Always looks dry as a bone, but I’d def be cautious with render, I did a big planter at the same time in blockwork and rendered it (other pic) and despite lining the inside where the soil is with black polythene, 3 years on the render and paint aren’t looking too hot ...other rendering I’ve done is fine so suspect it’s still the moisture issue...crap uk weather etc

 

[Ian H]

The first pic is exactly as I imagine it but with the lawn higher

 

[23vc]

Yeah it’s not that high now I look back at it. I cut back the soil about 6 inches behind, down to top of footing and filled with hardcore. But like you say yours might need some better drainage, sure someone who knows more will comment

 

[noseall]

Protecting the back (from soil contact) is a good idea, no matter what.

 

[^woody^]

In this situation, you won't need a membrane as there is no risk of the gravel silting up. Polythene up the wall would be a good thing though.

 

[Ian H]

Would you say a 1200 visqueen or rigid plastic board?

 

[noseall]

Would you say a 1200 visqueen or rigid plastic board?

Either. Whatever is easiest to install.

Poly can be easily trimmed off.

 

[Ian H]

How's about 2 x 140mm blocks on top of each other as normal?

Would they have enough strength?

I'm thinking they would be cheaper and quicker.

 

[^woody^]

That's a kerb not a retaining wall.

 

[Ian H]

I ended up building it from some stone that was previously 2 smaller walls up the garden. I didn't bother with drainage because they are just stacked dry.

Reason being it was free and I had a few days off work. I hope it stays up but if it doesn't it won't be too bad to change it.