cement fibre board and sand cement render.

[macmain]

any help would be great.
been out the game for a bit, set up my own maintenance company (4yrs), so go easy, im after a way of bonding render to cement fibre board, tyring to build a garage/ workshop so external is paramount. trying to keep cost down hence sand cement , and metsec. i know the pre mixed renders are expensive.

done loads of metsec /lindab over the years including all partitioning and ceiling systems , if you could give us a heads up. ill run it past the father who is a freelance qs. :RpS_cursing:

 

[Fatarm]

Alright bud, sbr slurry for bonding on cement board, welcome to the forum by the way

 

[macmain]

sbr slurry? as first coat

 

[macmain]

what ratio would you mix it,,, and with what? cheers. and ist painted or troweled on...

 

[Fatarm]

No, 1 part sbr liquid, 1-2 part opc mix together to a slurry then apply to cement board by brush then scratch coat when it's still wet-tacky don't let the slurry dry before coating

 

[macmain]

is opc portland cement??? cheers fatarm... been reading about rend aid is it pretty much the same sort of stuff....

 

[macmain]

is opc portland cement??? cheers fatarm... been reading about rend aid is it pretty much the same sort of stuff....

 

[Fatarm]

Yeah Portland cement, I have never used rend aid to be honest, but some of the guys on here could give you good advice on it, mixed opinions from what I've seen on here, think it may be a bit pricey compared to sbr, but I've used sbr on cement board without problems, it's good s**t sticks to everything:RpS_thumbup:

 

[Fatarm]

Am I getting this right to assume you are building a garage with cement board outside? No brick- block work to render onto?

 

[plasterjfe]

There is still a massive chance you render will crack in time. i would dedfo advise a suitable base with mesh. no slurry needed.

 

[Fatarm]

I would only use fibreglass render mesh over the joints of the cement boards before scratch coat?

 

[macmain]

thats the idea... block on footings then metsec/lindab..... fibre board n render....

 

[theblones]

make sure its not a cement particle board containing wood chip. the wood expands when damp

 

[Runswithscissors]

McMain
You are making a good choice in building a leightweight, fast build garage - nice one!
Get in touch with me (contact details in my profile), I will help you out with the details of fitting Knauf Aquapanel Exterior Cement Board as a board in your application - base detail, head detail, windows, doors, etc....
As it is not a domestic residence, the build will be different to what i normally advise, but very similar to builds done elsewhere in the world using Knauf Aquapanel Exterior. As this is only a garage - it depends on you how you want to build it, how long you want it last and what finish you think will be acceptable......
It would be impartant that you at least tape and joint the boards before putting a S&C on. If you want the finish to last (not crack or get damaged by impact or even wind) we would advise the application of a 5mm basecoat and mesh to start off with - as JFE said above (you can then not tape and joing the boards, if you want). Then you can apply a S&C finish.
If you want some help, get in touch (I am on holiday until Monday - but send an E Mail, leave me a message or reply to this)
Good Luck
Richard

 

[Render Systems]

Why take a chance on sand and cement? it will crack... just put a thin coat system straight over the lafarge g-tech aquaboards... 3-4mm basecoat Parex Maite with mesh embedded and a 1.5mm topcoat tis will cost you
£9.00 Per m2 for the boards
£3.00 per m2 for the Maite
£1.00 per m2 for the Mesh
£5.00 per m2 for the topcoat