Board-formed concrete is cast against sawn timber so that the grain of the boards is transferred into the face of the wall. It is not a coating and it cannot be repaired: what comes out of the formwork is the finished surface.
The cost
Roughly 2.4 times the cost of a standard poured wall, most of which is formwork carpentry and the sheer number of test pours. We do four full-height test panels for every project and reject at least two.
Why we keep specifying it
Because it is one of very few finishes that improves over thirty years, and because it is honest about how the building stands up. It also removes an entire trade from site: nothing is plastered, nothing is painted, nothing needs redecorating in a decade.