HI spectral stacking techniques have recently been used to isolate the average signal from co-added low signal-to-noise observations of intermediate redshift galaxies. We will exploit these methods to extract HI information for galaxies which were classified as non-detections (i.e. $\leq$ 3sigma) in the Nançay Interstellar Baryon Legacy Extragalactic Survey (NIBLES). We will present the average HI content of galaxies selected according to a range of morphological and optical criteria with the aim to learn more about the HI distribution in galaxies in the Local Volume.

We will extend the use of these techniques to outline possible survey scenarios for a deep HI survey using MeerKAT. Future radio surveys aiming to quantify the average HI content of the universe over cosmic time will rely on HI stacking and co-adding techniques in order to push to the lowest mass limits achievable within reasonable observing timescales. Based on simulations we will present the resulting achievable HI mass limits at intermediate and high redshift for the different survey scenarios.