This paper addresses the problem of soundfield reconstruction over a large area using a distributed array of higher-order microphones. Given an area enclosed by the array, one can distinguish between two components of the soundfield: the interior soundfield generated by sources outside of the enclosed area and the exterior soundfield generated by sources inside the enclosed area. These components form an indistinguishable mixture and, despite the existence of theoretical solutions to separate them, practical implementation is challenging due to high number of microphones needed for large regions and high frequencies. In this work, we consider a scenario where the interior soundfield is characterized by reverberation and show how a set of RIR measurements can be used to parametrize the interior component as a function of the exterior component, effectively reducing the unknowns of the problem.