Summary Roof joint connects the upper roof structure to the lower RC columns in large‐span structures. However, during several earthquakes, concrete edge failure of roof joint observed in several previous earthquakes shows potential collapse damage of the large‐span structures. This paper presents an experimental and numerical study on the performance of roof joints under quasi‐static cyclic loading. The effects of concrete edge distance of anchor rods and using horizontally slotted holes in the base plate were investigated and discussed by means of ultimate shear resistances, failure modes, hysteretic responses, anchor strains, and stirrup strains. It was found that concrete edge failure was prone to occur if the edge distance was taken as per current design practice. However, with the use of slotted holes in the base plate, the concrete edge failure could be suppressed due to the sliding between the base plate and the mortar layer. A refined theoretical model was proposed to evaluate the ultimate shear resistance and predict the failure mode. Finite Element Models (FEMs) were also developed to verify the proposed theoretical model in terms of the ultimate shear resistance and the failure mode under both monotonic and cyclic loading.