Blocking RF on same side as PCB antenna?
With EMI\EMC it is more of an art. Your entire design would have to be considered. A rule I use is, EMI will take the lowest inductance pathway to return to ground. Increase the inductance and the radiation will be attenuated.  

If price isn't a consideration and you know it's a problem, put a shield on the part of the PCB you are worried about. There is a book that is a great reference and it has an entire chapter on shields and a section (6.16) on board level shields and a small bit on fences. You could always try a shield or a fence, but it will take some experimentation. It can be wise to devise several options that you can use to mitigate noise, test them out and see what works.