We establish an epsilon-regularity theorem at points in the free boundary of almost-minimizers of the energy \(\textrm{Per}_{w}(E)=\int _{\partial ^*E}w\,\textrm{d}\mathcal {H}^{n-1}\) , where w is a weight asymptotic to the distance function \(d(\cdot ,\mathbb {R}\setminus \Omega )^a\) near \(\partial \Omega \) and \(a>0\) . This implies that the boundaries of almost-minimizers are \(C^{1,\gamma _0}\) -surfaces that touch \(\partial \Omega \) orthogonally, up to a singular set \(\textrm{Sing}(\partial E)\) whose Hausdorff dimension satisfies the bound \(\text {dim}_\mathcal {H}(\textrm{Sing}(\partial E)) \le n +a -(5+\sqrt{8})\) .