Concrete finish - additives

[ricky]

Hi all,

Have just re-levelled the driveway flagstones, the 2ft gap between them is sound concrete, rough finished that originally had tarmac on, but has since been removed cleanly.

This rough concrete is now an average of 1-1 1/2" below the level of the flags so was going to lay down a layer of fine concete 6:1

What I'm not sure of is should I be using any additives ?

Is it best to prime to old concrete with a pva wash or just water ?

Should I be using any extras like waterproofers or frostproofer in the mix to help resists the bad winters ?

Finally, as the drive is on a fair slope and the flags being quiet smooth I was thinking of using the yard brush method to give it a non slip surface or possibly just the waviness produced by the leveling / tamper - or is there a nicer looking way of finishing it off.

thanks.

[seanandruby]

hi rick. At 1/12'' you need to use a grano mix ( see index ) . Add sbr and also prime base etc with a coat of sbr and neat cement.

[ricky]

Hi,

you need to use a grano mix ( see index )

Thanks for that, don't know how I missed reading about it ..? will pick some up today and try a batch.

[ricky]

Hi,

Just a follow on to the Grano - can it be used ok with the rapid set cements or would this upset the Grano's normal slow drying out ?

Thanks

[simeonronacrete]

Don't use PVA, use Ronafix (SBR). Much more capable of coping with damp and wet than PVA.

If you want a spec for a Ronafix modified granite screed see:

Ronafix Mix B or B1 granite screed

[seanandruby]

Just use normal cement, because grano goes off pretty quick. Don't have the mix too wet.

[ricky]

Thanks Guys