A constraint that can be used for modelling problems where a first set of tasks ${𝒯}_{1}$ has to cover a second set of tasks ${𝒯}_{2}$. Each task of ${𝒯}_{1}$ and ${𝒯}_{2}$ is defined by an origin, a duration and a height. At each point in time $t$ the sum of the heights of the tasks of the first set ${𝒯}_{1}$ that overlap $t$ has to be greater than or equal to the sum of the heights of the tasks of the second set ${𝒯}_{2}$ that also overlap $t$.