Purpose: The use of mixed-methods research (MMR) within building and construction research (BCR) is studied in detail. A new MMR paradigm, defined as ambiguous mixed-methods research (AMMR), is conceptualised within a BCR context. The paper aims to discuss these issues. Design/methodology/approach: Informal and inductive methodology combines experiential and anecdotal knowledge with synthesis of extant literature, to detail a cogent representation of the BCR research paradigm continuum. From this, the AMMR design is presented and its conceptualisation highlighted by reference to a small sample of published BCR studies. Findings: Paradoxically, the BCR paradigm continuum is dichotomous in its quantitative and qualitative extremes; while between these, coalesced paradigms permeate it. Influenced predominantly by worldview, many BCR researchers select a methodology that aligns with either continuum extreme. But, the authors conceptualise, in practice this often relies on ambiguous AMMR characteristics. Research limitations/implications: AMMR offers BCR research and beyond, a new approach for making, designing and defending methodological decisions. Originality/value: The AMMR paradigm was designed by the authors and is therefore entirely novel.