bonding advise please

[sheldon1982]

i have removed a wall from my sisters bedroom and studed a new wall up with 12.5m plasterboard. i now have the chimney beast on one side exposed brick. i would like to bond then skim this area as i have never done this before. i am quite good at skimming but have never used anything else from multi-finish. is bonding/hardwall the same as multi-finish as far as spreading it on the walls and mixing. what about stop beads because its an external corner where one side will be multi-finish up to the corner and then the other side will be the bonding + multi finish. hope that makes sense sorry.

 

[roughcaster]

There's a bit of work involved floating onto brickwork Sheldon.
Another solution for you maybe,,,, any chance you could fix a sheet of plasterboard over the brickwork instead, then you would just need to fix a thin coat bead on the now "plasterboard external corner", then you can just skim with multi as per normal,,,,, a much easier way for you in the long run, with the same result,, a nice neat corner.

 

[sheldon1982]

thanks for the reply roughcaster. i am probably going to fix a board to it but i have never used anything else from multi-finish and am very curiouse as to how it works. if its beyond my skills then i will leave it. i have been skimming walls/ceilings for 18 months now (diying) and have got to a decent level but thats all i have done.

 

[roughcaster]

Bonding coat is easy to mix and use. I mix it by hand. It has a different texture altogether compared to multi finish. Thicker,, It's like a porridge. You can mix it up thinner if you want to spread it tight/thinly,,, as if you were skimming, or you can mix it up thicker if you're wanting to use it as a thick float coat, say onto brick/block work. I use it all the time, every time, even if if it's onto new plasterboard. It give me a great backing coat for the multi, plus, you can easily blend away anything that comes along,, eg, an old doorframe,, bad joints in the boards themselves,, different levels ceilings/walls etc,, plus float coating. I wouldn't be without it. If they stopped making Bonding coat,, i'd quit plastering.

 

[sheldon1982]

so how should i tackle this one , do i wet the wall down or pva it, do i do two coats or one of bonding,and what about the corner bead? sorry for all the questions, just one more if you put it onto concrete or plasterboard do you have to pva first? thanks your advise is so much appreciated

 

[roughcaster]

The only thing with using Gypsum plaster onto old brickwork,, especially a chimney breast wall,, is the possibility of efflorescence/salts coming through the plaster. It's advisable to "scratch coat" any old brickwork first, with a 4 to 1 sand and cement render, with a waterproofer/plasticiser additive, in the mix first, then put on the bonding or hardwall coat.

 

[roughcaster]

Does the stud wall plasterboard meet the exact corner of the brickwork.

Example below:

Top row of dots = plasterboard stud wall.
Bottom 2 dots= chimney breast wall.

.................
.
.

 

[sheldon1982]

no the plasterboard meets the internal corner then the chimney comes out and then you have the brick external corner, hense my confusion with the corner beads, your right , there is a lot of work involved with the render

 

[sheldon1982]

example


.......................................... - plasterboard
.
. - brick chimney brest
.
.
..................... - external corner

hope this helps

 

[sheldon1982]

cant get the pic to work properly

 

[roughcaster]

That would be the ideal solution if poss! much easier to explain. It's more for the bead set up, than anything else. I'll keep looking out for you.