Screed on Concrete

[qubit]

Hi I've laid standard concrete slab inside and ready to lay screed on top (first time screeding though) need a good finish for real wood flooring don't wanna mess it up just a few quick q's plz

Roughly how wide should the perimeter screeding be?

Do you wait for the perimeter screeding to dry first (and how long does that take) and remove the battens then infill?

If you do leave the battens in and infill then do you remove them after finishing the rest then fill the gaps?

How long does the screed take to dry (I mean walking on dry not totally)

Oh and do you plastic float it like external render (that would be tough though since you can't rest on the wet screed you've laid while waiting for the previous to go off for an hour or so)

Any help greatly appreciated please

 

[noseall]

make no bones about it, screeding is tough work.

firstly the mix needs to be spot on and consistent. it is a semi dry mix that only requires enough water as to make it bind together when squeezed in your hand. any wetter and it will be hopeless.

you then work a perimeter screed around the room starting and finishing at the entrance doorway. i like to lay a broad perimeter screed usually about 1m from the wall. a small room could tolerate a smaller edge screed.

the 'infill screed' can then be ruled off using the perimeter screed as a guide. this is laid as soon as you have done the perimeter and no need to wait for it to go off.

i don't bother with screed bars, i just use a level a poly float and a floor trowel.

the loose screed is barrowed into the room and tipped up. i then knock it about with a shovel. i then compact it and roughly level it with the polyfloat, then i rule it off with a featheredge.

it is then rubbed up with the polyfloat and any hollows can be hand filled and rubbed in. then you give it a swipe with the floor trowel to compress the finish.

 

[noseall]

p.s. brush in a cement slurry binder to the concrete surface prior to laying the screed.

 

[qubit]

Thanks for the excellent reply Mr Nose

Maybe I'm thinking of screed being like render (i.e. fatty and wet) but I forgot it's so dry so is different

So you mean that the screed "holds" itself in position due to it being so dry without the need for battens to hold it, that's good news then

Also you seem to be saying that it doesn't need time to go off before floating like with render because there's no "fat" to bring to the surface that's also good news

So there's no timing involved in screeding? Correct me if I'm wrong thank you Mr Nose very informative reply

 

[noseall]

[quote="qubit";p="1049765"

Maybe I'm thinking of screed being like render (i.e. fatty and wet) but I forgot it's so dry so is different

absolutely.

So you mean that the screed "holds" itself in position due to it being so dry without the need for battens to hold it, that's good news then

yup.

Also you seem to be saying that it doesn't need time to go off before floating like with render because there's no "fat" to bring to the surface that's also good news

spot-on

So there's no timing involved in screeding? Correct me if I'm wrong thank you Mr Nose very informative reply

you have all the time in the world with screed. within reason.

 

[qubit]

Thanks for the confirmation Mr Nose

That makes me feel much better now ta

 

[chappers]

one thing i would say is ,unless you only have a small area to screed then consider buying the screed in ready mixed, it will be much easier to work than any screed you mix yourself. It should have the consistency of demerera sugar, without lumps and balls.

 

[qubit]

Thanx Mr Chappers I didn't get ready mix because I needed the sand and cement for different jobs. As long as it's not as hard as the 100mm concrete I had to mix (I'm sure 50mm screed has gotta be easier) it's okay plus I enjoy the excercise anyway

It's only 7m sq

I may have to get some demerera sugar to remind me it's been a while since I used that