Skimming on hardy board


Well-Known Member
Done it over blue grit before now mate, even skimmed over wedi board with just a lick of pva, no problems to my knowledge.


Private Member
Funnily enough I did same other week just pva and skimmed...didn't seem like the right thing to do as 1 side is smooth 1 rough...

Problem was i needed to dab first so again didn't want to dab to smooth side..

In the end rightly or wrongly I dabbed rough side pva and skimmed smooth side
Hi suction board, treat it accordingly. You can skim it and render it, no problem.


Well-Known Member
Grit and skim would be my thoughts but I'm a dirty courser so probably wrong


Active Member
Pva won't hold on it so use something else like blue grit as said above.


Active Member
I've found it peals off but maybe it's the cheap Pva I used. I used wickes plaster sealer over the last lot of board as just happened to have some, then a Pva with no problem. I really liking gardz as a problem solved sealer at the moment


Private Member
I dunno what your all arguing over it will crack like f feck anyway and prob drop off regardless in a couple of years
It will eggshell with pva. Blue grit is the only real chance
Love CBD


Private Member
I am guessing from the size of the vent the log burner will be over 6 bt u and from the flue pipe sticking through the wall that an insulated clue is not being fitted so, given how close that flue position is to where the fire will end up it WILL crack around the flue. I am not talking small hairline stuff either. Baffle plates fitted around the flue sometimes hide them .


Bum Fisting Club
I’m going to throw a curveball in.

How about replacing that cement board for plasterboard
That was my first reaction, client asked about the heat implications


Active Member
That was my first reaction, client asked about the heat implications
Pboard won't take the heat. Neither will skim. Or anything gypsum based.

Need victas stuff.

Or just get it tiled.

On a side note, you can skim cement board if gritted. Had to do it in a bathroom once where shower area had been cement boarded wider than enclosure. Blended to plasterboard one side and lime float the other no problems.


Active Member
There must be 15+ primer sealers on the market. We are all never going to agree on which is best for what. Guess what ever works for you. Blue grit. BG do various sorts. Sbr. Pva. Zinnser make a few gardz being one I use. Acrylic primer undercoat for wood and plaster. Wickes do one similar to artex sealer. Artex Sealer if you can get it. Dulux plaster sealer blue. That green rubber stuff called Cementone Plasterers Stabilising. And the list goes on.


Well-Known Member
Pva, blue grit, repeat,hardwall,pva bond scratch blue grit then skim and then wait for it...... SBR and cement slurry then I reckon top off with a nice coloured render... lovely job