Hi Liana / Louise
The home was a single storey and was done approx 9 years ago. It still looks the same as the day it was installed and there are no cracks.
It also meant timing was shorter as we went from slab down to lock up in approx 4 weeks (ie roof on, windows in, cladding etc)
RE maintenance, a pressure wash every 18 months or so depending on location is all it needs. If you want to keep it looking new, you could re-coat it every 10 years. I do not paint over texture coat but you certainly can do that.
RE thermal performance, the entire system far exceeds brick. A standard double brick cavity wall R value is around R 0.5 from memory. The Hebel allows for an R2.0 batt in the stud work which takes you to a total of around R3.0, or approx 6 times greater than brick without the thermal mass.
We also found that unlike brick, the walls didn't radiate heat into the house at night and aircon wasn't often needed ( I like it cool at night)
As I said previously, the methodology is important.
For example, during the design of the house the stud framing capacity needs to take into account the fact that the Hebel is being used.
The panel size (height) needs to be selected and laid out taking into account both the set down in the slab (exterior course is lower than internal) and the height to the eaves + 50mm. I always go a longer panel so that I don't have joins everywhere rather than patching short ends
Control joints need to be properly spaced (these are the gaps in the panels at long intervals to allow for movement that are caulked)
Positioning items such as window in increments of 300mm from each other eliminates extra joins and pieces.
In relation to cracks, the use of a textured acrylic such as Acratex means it is an elastic (movable) finish and if it is properly installed you should have no issues.
I have seen people just render and paint the exterior and as this isn't flexible enough it will likely crack. I would not do it this way and do not ever recommend a render.
Texture coating is the more expensive finish but is far and away the most durable in this case. As an aside, upmarket homes are almost always texture coated here in WA.
I would suggest you simply take your plans to your local CSR Hebel supplier and work with them. They will plan the panel layout for the job with you or the builder can do it with them. The supplier will also point out changes that can be made to your advantage ie panel sizes, joint locations in effect all the things I have mentioned above they will do.
There is also a web site available called Hebel Matters that is a blog style and you can get lots of info from that.
RE the foam, we had experience with that in Melbourne when we lived there and I am not a fan of it for anything other than a second storey.
As I said at the outset, if you set it up properly and finish it in a quality texture, you will not regret doing it for the advantages you gain in thermal performance.
Cheers
Q
