Finish coat plaster onto concrete

evilgoose

Hello - I'm wondering - can you apply a finish coat (top skim, or what ever you call it?) to an internal wall which has a level and key'd basecoat of concrete? -

or should a browning or base layer of somesort of plaster be applied?

or is it best not to have the concrete and just go straight on with a browncoat/basecoat of plaster?

(the walls are a mix of brick and cinderblock with some concrete joints and some black mortar joints)

thanks!!

Plasterer

If you mean like this below - then yes you can skim straight onto it (Have to pva it first though )



This is the cheapest and in my view the best way of doing it.

evilgoose

thats exactly it - great thanks for the help!

Radsteral

on concrete you need to follow this .

thistle bond-it -a strong glue premixed with sand) applied on concrete and left 24 hours at least
a thin coat of bonding applied and skimmmed same day if you are really fast.. if not, bomding today and skim next day.

you defenitely need to use thistle bond-it(50 quid for 10 litre tub on travis perkins) as pva and unibond dont work on concrete- if you pva, it ll stick but as soon as its fully dry it ll fall of easily
type ''british gypsum thistle bond it'' in google for more
me=20 years plasterer so you got no choice but to take my advice

evilgoose

a thin coat of bonding applied and skimmmed same day if you are really fast.. if not, bomding today and skim next day.

reading about the bonding - it says it should be applied 11mm thick - if the concrete rough coat is 10mm think - then + the bonding + 2mm skim - it going be really thick.

Can the you use the bond-it then skim ontop of that?

thanks,

Plasterer

evilgoose wrote: »

reading about the bonding - it says it should be applied 11mm thick - if the concrete rough coat is 10mm think - then + the bonding + 2mm skim - it going be really thick.

Can the you use the bond-it then skim ontop of that?

thanks,

Listen carefully, I will only say this once. If you have "Wet plastered" the wall as above and "scratched" it then you can skim multifinish straight onto it after PVAing (Yes 24 hours before) and maybe before you skim. The PVA needs to be watered down NEVER NEAT Plasterer 15 years, Own Limited company, four lads on the books..... Thistle "bond it" is a product that is less than ten years old...... Wonder what all the plasterers out there used before this magical MUST USE MUST HAVE Blah blah blah product.....
Not digging, just saying it the way it is (Many ways to skin a cat)
Choice is yours, in my veiw if you do it the other way you are wasting your money. Good lcuk with whatever you choose.

Would you please do the honour of telling us what you decide to do and how it turns out
Regards
P

And just to illustrate below is the same wall skimmed, No Bonding coat, no magical thistle this thistle that.

booty40uk

Do what Plasterer says.

Plasterer

Or get a couple of these from B&Q to give you a hand..




:rotfl::rotfl::rotfl::rotfl::rotfl:

evilgoose

Thanks for the advice - I'm not sure just yet! But will let you know.