Raised vegatable bed wall - foundation method

[3ps]

Hi,

I've been planning to do proper brick built raised beds for years and I think this spring/summer is it....

I am going to use some form of buff/gold concrete block from the likes of Tobermore, and they will be quite low... probably about 1 foot high so a couple of courses depending on brick size.

In some places they will be higher, but maybe only 2-3 foot.

I want to be able to do it bit by bit and my main concern is making the foundations. Would prefer to do it all in one go and then start bricklaying. I have ~250 foot to do.

I am not sure if I should have some kind of wet mix that I pour into the trenches..... but this means I have to be on-the-ball and make sure for each (large) rectangle of about 60-70foot that I have all the materials ready and can mix and pour and let it settle in the entire trench in one go to get the right height.

Or, should I use some kind of dry mix. I saw a video, maybe Marshalls, where they had a dry mix in the trench and used a long spirit level to work sections flat and level. It seemed quite easy.

I would prefer to use the dry method..... is it OK?

Here is the video... especially 55s and 1m40s:
https://www.youtube.com/watch?v=IzM23fh8h98

I'm a DIYer and not very experienced... but I can handle a lot... just need some reassurance before I proceed!

Thanks.

[dig dug dan]

Never used a dry mix for a wall foundation personally. Wet is better, easy to level and tamp.
to get it level, I bang in metal pins all at the same height that you want to have the finished concrete set to, marl where they are on the ground so you can find them, then when you fill the trench with concrete, you can find the top of the pins with the shovel, and scrape excess back.
if you set the pins about 6 foot apart, the use a long tamp board, such as a 4x2, each end will rest on the pins to get the final height.
others may have a different methods.
best to pour them all in one hit too

[rxbren]

Laser level is king for levelling footings
Personally if you have 1m3 or more of concrete id get it delivered by a volumetric mixer

[3ps]

Thanks.

I'm really reluctant to have it wet as if I am working on my own and have so much to do, I don't think I can manage it all in one go.
Even if I split it up bed by bed... I am looking at ~70foot to level each time... I will be mixing like billy-oh try to get it all full enough to level it off... or I might run out and not have enough. Just feel nervous about the quantity.

For volumetric.. would access is a problem for me. I'm not really sure it could be delivered to the back of my garden without great expense... it's probably about 100foot.

[rxbren]

rope in 3 or 4 mates with wheelbarrows
mixing vast amounts of concrete is a ballache, its time consuming and cost wise once your over a 1m3 its normally cheaper ready mixed
example c25 concrete 2 bulk bags of ballast (youll need alittle less than two full bags but give or take £80) and 13 bags of cement ( around £65) so thats £145 per m3 plus how ever long it takes to mix and pour

[seanandruby]

You also need to take in to account the different widths and depths for the higher/wider parts. Will the founds' be one height, or stepped? The dry concrete is to labour intensive, you don't wanna be on your hands and knees doing footings, especially over that length, wet it up a bit more it will be easier to level out standing up . If your set on doing it by hand a bit at a time then just mix, lay and level as you go, when you have had enough stop end it and place rebar in the end then continue next time. Make yourself a t tamp. Anything you can do to make it easier, do it as concrete is unforgiving when it starts going off.

[jwill]

Always easier with two. Nobody that can gov you a hand?

[3ps]

Thanks.

I can rope somebody in but not sure I can put up with his 'advice' for too long!

I guess I understand my options now....

- dry mix bit by bit but might be labour intensive (I dont' really mind I'm not doing anything else and I can spend all spring/summary at if it I want)
- wet mix, easier but I have to do sections in one go.

Just need to know if anybody thinks the dry mix method would be more print to failure?
My wife uses a 'no-dig' gardening method so the walls just need to be 2-3 courses high to define areas, rather than be high raised beds.

[seanandruby]

You don't have to do sections, you can do as much as you can, or all of it, it's your call. Yes wet mix.

[3ps]

I must be not understanding something basic with all this!

Let's just say I have 3 raised beds to do.... each one is 25 foot x 10 foot.... so each bed has footings of 70 foot of some width and depth.

To me, the smallest thing I can work on is 70foot ... I can't break it down into sections smaller than that with wet mix as I need to fill it all to get the level right.

I was thinking with the dry mix it would be easier for me to work my way around and if for some reason I ran out of materials half way along... just stick some bar in and start again easily.

NOOB ALERT!

[rxbren]

I cant work in feet lol

Length x width x depth gives you the total volume add 10% ish for wastage (overdug areas, sides alittle wider here and there)
if you do it wet and are goung to end up short you can put in a stopend (sheet of timber or blocks what ever gives you a stop) if you use a sheet of timber you can drill hokes and place the rebar in ready to be concreted in place otherwuse youll have to wait till concrete set remive stopend and drill and fix the rebar after wards

[seanandruby]

Why ask for advice if you are determined to lay it dry ??? You do one wet and do one dry then come back and tell us which was easiest to lay and level off :;):

[rxbren]

To be fair you cant help some people
Amouny of tumes that some people get an idea in there head and no matter how many times they get advised not to do it that way, the just carried on regardless or just want to hear sure it will be fine just do it that way.
Best example was a lad doing a track car no matter how much advice he got he carried on, he had issues with parts failing which led to a crash and to top it off later had a fire but at no point has he held hos hands up and said i was wrong

[seanandruby]

Very true Rxbn. Times when i have been forced to do dry blinding, even that had a wacker over it. 3 course, or 10 course a footing needs to be done right.

[dig dug dan]

This all seems a lot of effort for very small amount of brickwork.
when not build from new sleepers?