Ion conducting aerogels are a new class of superionic conductors expected to have interesting properties. Aerogels are extremely porous and have very high surface area. Such porous materials often exhibit self-similarity in structure within certain length scales, so they can be modelled as fractals. This is confirmed by small angle neutron and x-ray scattering experiments. In the present paper we suggest a simple fractal model which is consistent with the different data available on typical aerogels. We construct a basic fractal unit which is repeated in a periodic array to form the gel. We assume a surface conductivity sigma(s) different from the bulk conductivity sigma(b). As porosity increases the proportion of the bulk material decreases but surface area increases. We have studied the effective conductivity of the aerogel resulting from the competing effects for different sigma(s)/sigma(b) ratios. We expect such studies to be helpful in tailoring new superionic materials for specific use.