Are WPC terrace boards suitable for exterior walls?

How did you clad it?

Not at all yet. But I will use rhombus slats (maybe pre-grayed). WPC would be too expensive and look crap to me...

These floorboards are more expensive than wall paneling! For example, you can use planed battens or have 12cm smooth-edged boards cut down to 6cm (or 14 to 7 etc.) at the sawmill, or take the whole boards and then screw them like rhombus strips onto battens, lengthwise or crosswise, painted or raw. It can be designed nicely, costs little, and you can even hang plants or screw other things on. Easy to do, inexpensive, and customizable.

When it comes to a wood facade cladding that aims to avoid the "there are twenty of these in this building area" effect at popular prices, I would simply copy the basic idea from of installing a "wild pattern" made of differently wide slats.

When it comes to a wooden facade cladding that is supposed to avoid the "this exists twenty times in this residential area" effect at populist conditions, I would simply copy the basic idea from to install a "wild pattern" of slats of different widths.

What do you mean by "wild pattern"?
Randomly placing the slats?

What do you mean by "wild association"?
Set the skirting boards all over the place?

No, I had also put it in quotation marks. Here you can see examples: or also or