5Ghz is extremely poor at penetrating objects. Unless you are only penetrating a single wall, preferably at not too steep of an angle, and the distance is minimal, then you will probably have issues. The upside to this is that in a crowded environment your neighbors 5Ghz does not tend to interfere to the extent that 2.4Ghz wifi does. If you have a challenging location you may very well get better performance with 2.4Ghz vs. 5Ghz even if you could connect. The real benefits of 5Ghz are found when you are in the same room as your access point.