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Hi all,
I’m refurbing my ground floor bathroom and putting in a level access shower. The floor is a basic slab/foam insulation/screed construction and I’ve dug out the necessary existing screed to position the Impey Aquagrade screed former which I’ll be using to help create the correct falls to drain. I want to get this done over the Christmas break.
I’ve not done any screeding before. For this purpose the instructions say it’s a dryish 4:1 sand/cement mix but I’m a bit bewildered by the number of different types of cement available. Can anyone offer any recommendations of which materials to get from e.g. Wickes?
Also appreciate any tips/ general things to look out for when doing the job.
cheers!
Some info here http://www.screedscientist.com/floor-screeding/
I would have thought that a CEM I or CEM II would be fine (you'll probably have to look in the small print to see that on the bag though)
[I am not a screeder...]
Just a standard opc will be fine.
Ordinary Portland cement.
And you'll be mixing it with washed sand or sharp sand, both the same, do not use ballast.
Thanks both, so I don’t need any reinforcement fibres or additives etc in the screed? Would either be beneficial at all?
Can I use an additive to make it harden/dry faster?
Most of the cement sold in DIY stores will be a CEM II blend - which will be lower strength (32,5 or maybe 42,5), but is likely to make a more workable mix (due to what's in the CEM II blend - usually cement plus a proportion of either fine limestone, PFA or GGBS). CEM I is getting increasingly difficult to buy - you might be able to get some in your local builder's merchant - it is likely to be higher strength (52,5) and is what used to be called OPC.
Get some friends to mix and wheel the barrows
All these years ive worked with cement ive never looked to see if its cem 1 or 2, I just use mostly rugby, castle, blue circle even quinn but always from paper bags easy to half a bag no waste with a belle mixer
I would think if you have never layed a screed before getting it mixed properly will be more of a problem as a drier mix will stick to the back of the mixer, too wet and your run will slump level
Use either a wood or polyurethane float and straight edge, make sure its compacted
If you have a lot to do you can also buy ready mixed floor screed
I recently screed 15m2 of utility room/ WC using Arditex NA (powder and latex mix). Recommended by a couple of builder mates. Brilliant stuff. Easy to mix and levels out nicely with a trowel and spiked roller. Also sticks to anything below - no need to prep/seal beforehand.
Will be laying the laminate and vinyl this weekend.
Well i must be bored tonight but just checked what cement i use actually is
Rugby is cem1 42.5
Castle cem2 32.5
Blue circle too dear for me but guessing paper bag cem1 mastercrete cem 2
All goes hard but i do prefer the rugby
Back to the fitba now
spacemonkey - Member
I recently screed 15m2 of utility room/ WC using Arditex NA (powder and latex mix). Recommended by a couple of builder mates. Brilliant stuff. Easy to mix and levels out nicely with a trowel and spiked roller. Also sticks to anything below - no need to prep/seal beforehand.Will be laying the laminate and vinyl this weekend.
Cheers, but I think that's more of a self levelling stuff?
At this point I need to fill in a shallow pit and also I don't actually want it to self level as I'm forming falls to drain for a shower.
This Arditex stuff may be good for later on when I lay electric UFH and use liquid screed to encapsulate it and form the top surface to tile on?