A vacuum insulating panel includes may include: a first substrate; a second substrate; a plurality of spacers provided in a gap between at least the first and second substrates, wherein the gap is at a pressure less than atmospheric pressure; a seal provided between at least the first and second substrates, the seal comprising a first seal layer and/or a second seal layer; and wherein the first seal layer may include from about 20-80 wt. % tellurium oxide, the tellurium oxide comprising TeO.sub.4 and TeO.sub.3, and wherein the first seal layer comprises more TeO.sub.3 than TeO.sub.4 by wt. %.