Query about shuttering for concrete - Any advice appreciated...

[Slabhead]

Hey peeps,
Could anybody give advice regarding shuttering for a concrete pour....?
I’m in the early stages of making a concrete base for a garden room which will be about 5x5m.

I don’t want to dig down anymore (I need to raise it up if anything), as I can get enough slant for a toilet waste pipe).

Is it ok to build up shuttering using pressure treated 9x2’s, which will be securely staked into the ground, then use a whacker plate to tamp down 3� of mot type 1....and then fill the remaining 6� with poured concrete.

But my main query being - is it ok to leave the shuttering in situ so it holds everything in place - especially the m.o.t?

Sorry if my details area bit vague - I can give more details if it helps provide an answer.
Any help/ advice is very much appreciated.

[lutonlagerlout]

no
eventually that shuttering will rot and the type 1 will disperse
you need a toe in the concrete down to below ground level
also a DPM will stops salts getting into the concrete
and mesh
LLL

[seanandruby]

see here
Could use the deeper edgings to contain mot.

[Slabhead]

Thanks guys...

I'm not sure what a 'toe' means ???

I have a DPM ready and waiting....mesh is on order.

Edging stones is a great tip - thanks

[seanandruby]

A toe is a part of a cantilevered slab for retaining walls. You have a heel which is a lit wider than the toe and takes the backfill which so the weight keeps it from tilting. The toe is on the front of the slab which can. It is an engineering process which involves rebar in the base slab with raiser bars sloping up into the wall and starter bars sticking out of base slab. We use toe terminology loosely on an ordinary footing.

[Slabhead]

Could I make a 'frame' using those edging stones, and hold them up with rebar rods behind them...then fill this 'edging stone frame' with the type 1 and whacker plate down.
Then, place my timber shuttering on top of the edging stone frame (also held in place securely), which can then be filled with poured concrete?

[seanandruby]

Slabhead your overthinking this. Sounds like you only need 9" just place a shutter and concrete up against it. Tamp the concrete inside shutter with some 4x2 and bang the sides with an hammer to help settle concrete and give a good finish to the upstand. Your concrete upstand should be just concrete. The slab can be laid on mot. Good luck i'm sure you'll be fine.