Originally Posted by Peter Sweeney
Cement board finish is fine if installed to NSAI installation standards, however there is little room from error.
If movement joints and staggering of cement boards are not fitted to exacting standards numerous hairline cracks will certainly appear over time as the timber structure drys out.
Even if the boards are fitted to standards, movement in the timber structure can result in cracking at corners and above and below window / door openings beyond the control of the cement board fitter.
These cracks in the cement boards would not normally be structural but can look unsightly especially if your selling your property.
If using cement boards insure that the cement boards are certified to be used in Ireland and also treble check the references of the installer.
I know of 3 buildings done in cement board in recent times: €73 was the lowest price that could be got, and is effectively doing it at cost price. We had it done on two facades here, same. I got a price of €28.5 per sq m for block wall as cladding c/w nap plaster finish, so you're prices are about right.
Now, I know of an extension to a house being built, and it's being done in a non-NSAI board, and the cost is €45 per sq m or thereabouts - as NSAI actually don't do any physical testing you can debate for yourself whether you think the badge is worth the extra €€. The board in question does have certification from another jurisdiction. (no connection, btw, but it's a subject that comes up a lot here).
As for Peter's comment about cement-board on moving on expanding/contracting TF, whilst technically possible, I thing it's more likely it's the quality of the timber used as battening, and the fixing method of it (nails, when you should use screws) that's the issue - not the TF. If movement in TF is of concern, OP could consider one of the other timber based, but non TF systems.