Retaining wall drainage - Is this shingle suitable

davowolf · Post: # 101330Post **davowolf** Mon Oct 27, 2014 1:41 pm

I'll try to post a photo of the shingle proposed to back a retaining wall and supply weep holes. I'd be grateful for your opinion on its suitability. (its a Google Picassa link 'cause I don't have a web site).

https://plus.google.com/photos....6187924

r896neo · Post: # 101332Post **r896neo** Mon Oct 27, 2014 6:35 pm

Its a bit smaller than I would use, looks like pipe bedding. Also any sand or dirt in it is sure to reduce the effectiveness and cause problems.

20mm clean stone would be better. If its not a big wall it may well do.

Mon Oct 27, 2014 7:24 pm

thats what is specified around these parts

dont forget the terram or similar to stop mud from the garden clogging up the drainage

how is your garden going davowolf?

I had to go and look at another failed retaining wall today, one thing for certain if they arent done right they will fail

cheers LLL

davowolf · Post: # 101345Post **davowolf** Tue Oct 28, 2014 2:11 pm

Thanks fellas.

I specified clean stone, either A10 pipe bedding or Type 3 sub-base, but thats what the builders got. Its in situ now so nothing can be done. There is a bit more needed (on the right as you look, of the following picture) and I have asked that if there's a choice to please get 20mm clean but there was some 'resistance'.

Any way here's the job today Tony - its taken us all this time to get it sorted.

https://plus.google.com/photos....ner=pwa

In most other respects the boys are actually doing a good job and working hard.

Tue Oct 28, 2014 5:39 pm

crikey that is a long time
looking good though,i saw a retaining wall that i priced 2 years ago at the weekend
it has failed I will post some pics later

the drainage weephole aspect is critical

LLL

davowolf · Post: # 101361Post **davowolf** Wed Oct 29, 2014 1:16 pm

Here's a few more photos of the wall to show the shingle in situ.

It has a very amorphous consistency with a lot of fines in it and all sizes from fine sand up to about 10mm.

https://plus.google.com/photos....ner=pwa

If you pick up a handful it leaves a fine sand residue on your hand. These fines are going to work their way to the bottom and risk blocking the weep holes over time. The weep holes are oval electrical conduit and being so, more prone to blocking I would have thought.

Post: # 101362Post **seanandruby** Wed Oct 29, 2014 2:55 pm

Should of gone for washed stone.
this is good stuff

davowolf · Post: # 101363Post **davowolf** Wed Oct 29, 2014 3:21 pm

I've resolved this issue in the last hour. Jewson's do a 20mm shingle and in the photos in this post you'll see the comparison.

https://plus.google.com/photos....ner=pwa

I've offered to buy myself (the customer) two 850kg bags of the 20mm and the builder has (reluctantly) agreed to dig out the smaller stuff he'd already placed in the wall.

Tony, thanks for your input; in the end I managed to persuade the builder to go with the 20mm without any independent advice.

Can't emphasise enough at this stage though that in all other respects these boys are doing a fine job. David the bricklayer as I write, for example is tackling a field flint panel - for him a first time doing this .... brave of him, and doing a fine job.

I'll post final pictures when its all over in about a week or so.

So how does this 20mm stuff compare with the 'washed' - which Jewsons didn't have ?

Can we wash it on site in the ton bag by just sticking a hose on it for half an hour ?

Wed Oct 29, 2014 10:29 pm

here is a sad example of lads who just built a 9 inch wall with no though to drainage

its a shame but that wall is less than 18 months old

LLL

davowolf · Post: # 101368Post **davowolf** Thu Oct 30, 2014 1:47 pm

Brilliant Tony.

That Jewsons 20mm in my second picture isn't sold as 'clean' - they didn't have any with that description. It doesn't seem too bad to my eye.

The previous smaller 10mm stuff was obviously full of fines though and is being 'extracted' this weekend.

Can anyone give a supplier (HP5 Chesham area) of the clean stuff so I can get it delivered ?

davowolf · Post: # 101369Post **davowolf** Thu Oct 30, 2014 1:48 pm

PS How do I get pictures to post like that ?

Thu Oct 30, 2014 5:16 pm

davowolf the stuff your blokes were using isnt really wrong
we use 10 mm pea shingle for this all the time
tony's drawing shows 10-20mm shingle ,most that we pick up is clean,but you can clean it with a hosepipe on sprinkler before installing
how to post photies is on the main noticeboard

cheers LLL