An extended scalar sector often emerges in models motivated by the electroweak hierarchy problem. A SM triplet is interesting because its decay is very constrained at the renormalizable level. Therefore, effective operators with a low cutoff make the triplet components decay promptly. In this talk, I will discuss the phenomenology of such triplet. In particular, I will show the reach of ongoing searches at the LHC, as well as projected bounds for the LHC-HL. The extended scalar sector also modifies the electroweak phase transition, which can be first-order and produce sizable gravitational waves. Therefore, I will also discuss the possibility of electroweak baryogenesis in this model and constraints from gravitational waves observatories.