Purpose: Ethnographic studies of, for instance, laboratory work show that practices never reach a full closure but are always open to contingencies and ambiguities, making it possible to accommodate new empirical findings. The aim of the paper is to demonstrate that this is true also for less "high-brow" work in, for example, the construction industry. Design/methodology/approach: A case study of a Swedish rock construction company is reported. Findings: The study suggests that activities accruing less prestige than scientific laboratory work also share this basic openness. In rock construction work, there is always uncertainty involved when engaging material resources such as equipment, tools and technologies and when exploring literary previously unknown ground. Practice is therefore what is of necessity and is simultaneously enclosed in terms of drawing on a relatively stable specific set of know-how, routines, beliefs, and norms, while remaining attentive to emerging events. Practical implications: Any practice must be regarded as resting on detailed know-how and experience and therefore the management of seemingly "low-skilled work" needs to be reconsidered as what is demanding informed vocabularies and insight in to the domain of practice. Originality/value: In theoretical terms the paper bridges practice theory, science and laboratory studies, and theory about construction work. In addition, the empirical study reported calls for a revaluation of the term "low-skilled work".