Garden retaining wall + drainage

[job_bodger]

Hi, I am hoping someone could answer 1 or 2 questions. I'm going to build a retaining wall in the back garden out of common red brick. Basically at the moment my garden lawn is sloping towards the conservatory and abutting it above the damp course and moisture is starting to set in (and the garden lawn at the bottom of the slope tends to get water logged). To solve the problem I wanted to create a small path between the conservatory and lawn and build a 70cm high retaining wall so I can level off the lawn and stop it sloping.
What is the best method for this?

1 or 2 layered red brick wall ? Or 1 layer of red brick and 1 of breeze blocks ?

Do I have to back fill with non compacted clean stone for drainage ? If so what does this entail?

What should I use as foundation for the wall ? Concrete or compacted gravel ? I presume concrete, if so should it be 12 or 18 inches deep ?

Does anyone know of the typical problems you run in to ?


If theres any budding landscapers/builders out there any help would be much appreciated!

 

[noseall]

build the wall twin skin.

1 leaf of 7n dense concrete blocks and 1 leaf of facing bricks tied together with s.s. housing ties.
you will need to return any open ends with facing bricks as to hide the blockwork - same with the uppermost courses.

you could lay the concrete 9" thick but be sure to make it 12" wider than the finished wall thickness. this will give you a 6" foundation 'toe' each side of the wall. dig down to unmolested, non-fertile ground.

if it is boggy clay substrate then the odd weep hole won't go amiss. we use 63mm square downpipe as this is the same thickness as a brick and gives a neat finish.

if you happen to have some hard core or brick ends, it wouldn't hurt to back-fill with this first.

 

[job_bodger]

cheers for the info

What does the back fill do ? Is it to allow drainage behind the wall to prevent the wall from being constantly damp ?

Also do I definitely need ties for a small wall ?

thanks

stuart

 

[noseall]

[quote="job_bodger";p="900063"

What does the back fill do ? Is it to allow drainage behind the wall to prevent the wall from being constantly damp ?

no. it just allows any water to percolate to the bottom of the wall - where the strength is and the frost ain't.

Also do I definitely need ties for a small wall ?

no you don't. but it may help prevent leaf separation. you are correct in thinking this is unlikely.



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