Retaining walls

[daiking]

I realise retaining walls need to be taken very seriously but...

 

ball park, a <1m high wall holding back <3m wide section of soil with a slab or patio on top is not good to be a major feat of engineering, is it?

 

I am unlikely to need professional input am I?

[Daedalus]

I am loathe to give this sort of advice over the internet but...

 

You can get away with a 215 thick brickwork wall (bonded together) with a half decent strip footing can retain 750mm. A good google search can provide some standard details little brickwork retaining walls.

[daiking]

8 minutes ago, Daedalus said:

I am loathe to give this sort of advice over the internet but...

 

You can get away with a 215 thick brickwork wall (bonded together) with a half decent strip footing can retain 750mm. A good google search can provide some standard details little brickwork retaining walls.

Cheers but I'm not quite 'there' yet but I am trying to see how involved a bit of work will be. 

 

Im just after the general principle that the sort of loading I'm looking at is easily dealt with, basically coming out a couple of metres from the bifold doors in these pictures

 

 

Edited February 2, 2017 by daiking

[Auchlossen]

You could use gabions. 1m wide will support 1m high. On Type1 foundation. There are lots of websites that offer guidelines.

Alternatively if you asked my engineer, he would design you a concrete slab as footing for a RC wall, with 0.5m toe to resist against slip movement, and it would hold up most of the elephants that you expect to entertain on the patio during the forthcoming earthquake.

[Onoff]

You're going to want a handrail across the front of the deck of course if a metre high, no? And down the steps.

 

Need to consider how you integrate that into your retaining wall or bolt to the front etc.

 

 

[Jeremy Harris]

 I knocked up a spreadsheet for doing gravity retaining wall calcs a few years ago, as I did all the design calcs for our big (3m high, 35m long) retaining wall, and looked at several methods, including using gabions.  In the end I needed an SE's sign off, so "came to an arrangement" with a very helpful and friendly local SE.

 

There are significant liability issues with any retaining wall over a metre or so high, but up to 1.2m I think you're fine with a DIY design.  If you wanted me to run a gabion design through the calcs, then I could probably do it this coming weekend, but I'd need some details of the soil type, the max allowable bearing load of the ground under the wall, whether there is any additional imposed load above from a slope, path, drive etc.  Running the calcs is maybe half an hours work after that.

Edited February 2, 2017 by JSHarris
typo "and" when I meant "an"

[Declan52]

I used a dry build type block to construct my retaining wall. The blocks are 450*300*150. You don't need a concrete founds just a good sound base of compacted hardcore. The way they lock together they lean back at approx 80 degrees. That complete wall is over 20m long and at its highest 1.4m and I done it all in a day. Cost wise I think it was approx £600 just got the main retaining wall. 

The smaller wall facing you on the picture used a smaller block as they aren't suitable for the height you need to go. 

For a block wall 1m high I would start with a course 450mm wide then 2 courses at 330mm then a 215mm and then your coping. 

The most important aspect of any retaining wall is how you get rid of the water that will pool behind it. You need a French drain type system with a fine gravel behind the wall. 

[daiking]

Thanks all but easy tigers!

 

I'm right at the start of planning so the nod that I can make it up is fine. Options at a later date...

[Guest Alphonsox]

33 minutes ago, Declan52 said:

I used a dry build type block to construct my retaining wall. The blocks are 450*300*150. You don't need a concrete founds just a good sound base of compacted hardcore. The way they lock together they lean back at approx 80 degrees. That complete wall is over 20m long and at its highest 1.4m and I done it all in a day. Cost wise I think it was approx £600 just got the main retaining wall. 

The smaller wall facing you on the picture used a smaller block as they aren't suitable for the height you need to go. 

For a block wall 1m high I would start with a course 450mm wide then 2 courses at 330mm then a 215mm and then your coping. 

The most important aspect of any retaining wall is how you get rid of the water that will pool behind it. You need a French drain type system with a fine gravel behind the wall. 

 

 

@Declan52That looks extremely good, we need something very similar - Who makes the blocks ? Where did you get them from ?

Thanks

 

[Declan52]

1 minute ago, Alphonsox said:

 

 

@Declan52That looks extremely good, we need something very similar - Who makes the blocks ? Where did you get them from ?

Thanks

 

Tobermore have their version but I got mine from Acheson and Glover as I had an account there from buying blocks from them. They have a display at their base in Dungannon.

https://www.ag.uk.com/outside-rooms/products/garden-walling-products

[Roger440]

I too used the Acheson and Glover stuff to do a retaining wall. There blurb says no cals needed upto either 1 or 1.2 depending on the system if i recall correctly.

 

Dead easy to use. I used it because i was very near trees, so long term likely to be some movement which these should cope with and a brick wall wouldn't. I would never build a brick retaining or garden wall again.

 

 

[daiking]

To resurrect this topic, the main wall (approx 1m) is on hold but I am looking for a little feature just to support the edge of the lawn so it doesn't migrate down the bank to the stream.

 

Every 'professional' suggests sleepers but this seems OTT and expensive. I've seen this arrangement for flag stone retainers on paving expert http://www.pavingexpert.com/featur06.htm but this also involves quite a bit of work with concrete.

 

I do however have a stash of used scaffold boards and probably have enough to double up over the 15-20m length I need and wonder whether this would work? Concreting in some short posts to hold the boards?

 

I tried taking a photo of the bank but it is so overgrown you can't really see the scope of the job - which I don't think is that great. I think that just running the grass down the bank a little would hold it all together.

[Onoff]

Scaffold boards will rot pretty quick compared to sleepers in my experience. Maybe treat them AND staple some DPM either side? Water would drain down rather than sitting against them?

 

Could look quite good with short concrete posts. Are you meaning to double up in height or width on the boards?

[daiking]

55 minutes ago, Onoff said:

Scaffold boards will rot pretty quick compared to sleepers in my experience. Maybe treat them AND staple some DPM either side? Water would drain down rather than sitting against them?

 

Could look quite good with short concrete posts. Are you meaning to double up in height or width on the boards?

 

Double up in width.

 

Gravel boards would work I think. Putting in posts seems a lot less work than bedding and haunching something all the way along.

 

With sleepers, I'd need to do the bed prep, need expensive fasteners, expensive sleepers (double height at least).

 

I'm not actually trying to retain much, just hold the edge together and look reasonably tidy. There's a picture in the new garden thread, it's not exactly the grand canyon although it gets bigger further up toward the neighbours fence

Edited July 5, 2017 by daiking

[Ferdinand]

Back on. So I'll try and dig up what I had ready last time in order to post it :-).

 

It depends (of course) on what you are retaining - especially the height. I can confirm @daiking's paver battered slightly back arrangement from Paving Expert works well for 1-2ft. These pictured below are retaining a garden level which is about 12-18" higher than the pavement, and are standard 3x2 (I think) dimpled concrete pavers - 1970s version (as opposed to knobbly style 1950s Pressed Council Slabs). They were put in in about 1970 at the house I grew up in and still seem fine. 

 

I think one thing that might help clarify your options is to decide whether you want to do it in one step or two.

 

I would guess that they are simply haunched in concrete.

 

Interesting that they have not been disturbed significantly by the contemporaneous evergreen hedge (is not Lleylandii - something more civilised).

 

 

 

Ferdinand

 

Edited July 5, 2017 by Ferdinand

[Onoff]

I quite like the idea of gabions myself.

 

If I had the dosh I'd have loads made up in stainless steel mesh and just fill them gradually with flints from around the garden. Bug heaven, free draining and would last forever!

[daiking]

7 minutes ago, Onoff said:

I quite like the idea of gabions myself.

 

If I had the dosh I'd have loads made up in stainless steel mesh and just fill them gradually with flints from around the garden. Bug heaven, free draining and would last forever!

 

I like gabions myself but they take up quite a bit of space so not really an option for this short wall.

[daiking]

16 minutes ago, Ferdinand said:

Back on. So I'll try and dig up what I had ready last time in order to post it :-).

 

It depends (of course) on what you are retaining - especially the height. I can confirm @daiking's paver battered slightly back arrangement from Paving Expert works well for 1-2ft. These pictured below are retaining a garden level which is about 12-18" higher than the pavement, and are standard 3x2 (I think) dimpled concrete pavers - 1970s version (as opposed to knobbly style 1950s Pressed Council Slabs). They were put in in about 1970 at the house I grew up in and still seem fine. 

 

I think one thing that might help clarify your options is to decide whether you want to do it in one step or two.

 

I would guess that they are simply haunched in concrete.

 

Interesting that they have not been disturbed significantly by the contemporaneous evergreen hedge (is not Lleylandii - something more civilised).

 

 

 

 

Ferdinand

 

 

Simple and effective but looks like a lot of concrete to me which is a) hard work and b) more cost. So its not my preferred option at the moment.

Edited July 5, 2017 by daiking

[Ferdinand]

Just now, daiking said:

 

Simple and effective but looks like a lot of concrete to me which is a) hard work and b) more cost. So its not my preferred option at the moment.

 

]I can't comment on the amount of concrete, though I am just using a similar setup on the Little Brown Bungalow renovation for landscaping the front garden at a very modest height. Will ask the gent what he did.

[Onoff]

10 minutes ago, daiking said:

 

I like gabions myself but they take up quite a bit of space so not really an option for this short wall.

 

How about as the retaining wall and to support the deck? Picked at random:

 

https://www.manomano.co.uk/stone-fence-2508?model_id=1543249&referer_id=537135&gclid=EAIaIQobChMIjJKS0cjx1AIV5pXtCh0mXQVMEAQYBCABEgJVDvD_BwE

 

Fill with cheap stone or even crushed concrete? (That's the garage base gotten rid of )

[Ferdinand]

Can I throw one more suggestion in for now @daiking - Concrete Post Repair spurs are incredibly useful / flexible in this kind of thing.

 

They give you a tough concrete thing in the ground and you can bolt whatever you want to the top in the ready made hole - whether a ranch style fence, posts to make something a little larger, or even a couple of brackets for a seat.

 

I think they would be up to retaining 0.7m depending on the what is being retained, and how it is structured/built. At its simplest gravelboards could be wedged behind and help in by the mass.

 

Near here we have a pub backing on to countryside (Carpenters Arms Darley Dale - recommended and pleasant) which has fenced their entire car park with a wooden field fence where posts are all bolted to repair spurs, which is excellent for a long lived but attractive looking fence or retaining structure.

 

 

 

Ferdinand

 

 

 

 

 

Edited July 5, 2017 by Ferdinand

[PeterW]

 

You can get gabions in a variety of widths - we have some 600mm high ones that are only 300mm wide and they aren't going anywhere as they are wired together. Use them to "hide" all the old bricks etc and just face with stone. Weren't expensive either. 

[daiking]

55 minutes ago, Ferdinand said:

 

]I can't comment on the amount of concrete, though I am just using a similar setup on the Little Brown Bungalow renovation for landscaping the front garden at a very modest height. Will ask the gent what he did.

 

as it stands I have acquired a knackered old cement mixer that I don't even know still works and have no experience of making and working with cement and concrete.

 

46 minutes ago, Onoff said:

 

How about as the retaining wall and to support the deck? Picked at random:

 

https://www.manomano.co.uk/stone-fence-2508?model_id=1543249&referer_id=537135&gclid=EAIaIQobChMIjJKS0cjx1AIV5pXtCh0mXQVMEAQYBCABEgJVDvD_BwE

 

Fill with cheap stone or even crushed concrete? (That's the garage base gotten rid of )

 

I like them but the wife is not a fan for the large wall that would show them and I think they are a bit cumbersome for the short wall. I don't think I'm going to be getting crushed concrete anyway. It will be 'peckered' with the digger, and not crushed. A crusher makes no economic sense for small amounts.

 

37 minutes ago, Ferdinand said:

Can I throw one more suggestion in for now @daiking - Concrete Post Repair spurs are incredibly useful / flexible in this kind of thing.

 

They give you a tough concrete thing in the ground and you can bolt whatever you want to the top in the ready made hole - whether a ranch style fence, posts to make something a little larger, or even a couple of brackets for a seat.

 

I think they would be up to retaining 0.7m depending on the what is being retained, and how it is structured/built. At its simplest gravelboards could be wedged behind and help in by the mass.

 

Near here we have a pub backing on to countryside (Carpenters Arms Darley Dale - recommended and pleasant) which has fenced their entire car park with a wooden field fence where posts are all bolted to repair spurs, which is excellent for a long lived but attractive looking fence or retaining structure.

 

 

 

 

 

Ferdinand

 

 

 

 

 

Something like that although shorter than 1m would be even better.

 

21 minutes ago, PeterW said:

 

You can get gabions in a variety of widths - we have some 600mm high ones that are only 300mm wide and they aren't going anywhere as they are wired together. Use them to "hide" all the old bricks etc and just face with stone. Weren't expensive either. 

 

There's not that many old bricks now. A stack in the garage I'm keeping but certainly not enough to fill these. Even at 300mm wide these would take up quite a bit more space than I'd like them too.

[Ferdinand]

Unfortunately as far as I know 1.2m is standard for these.

 

You *could* just dig a deeper hole .

[daiking]

5 minutes ago, Ferdinand said:

Unfortunately as far as I know 1.2m is standard for these.

 

You *could* just dig a deeper hole .

A dozen+ times... and fix with post crete

 

Or get the digger to make a trench anf mix and lay 1 cubic m of concrete...