Which chicken breed can't fly apart from silkies?

Hi,
Im hoping to get some silkies soon but they don't seem to be around yet 

We were wondering what other breeds can't fly? We do have a fence but I want to be sure that they won't 'pop' over to the neighbours gardens, otherwise I'll be in trouble!
I want them to be friendly and queitish too.........I know Im asking a lot! 

It's probably more related to weight than breed. Most heavy birds won't attempt to fly.

In as much as, I have no intention of taking up tennis.

  Oh that's why I can't fly!

mooie, how high is your fence?  I have just got 6 heavy-breed pullets (see the breeds in my sig) who apparently will be unlikely to try flying when they are older as they gain weight.  But even at their young age (13 - 17 weeks) they show no desire to go over fences.  I have 6-ft fences around their run, but I think I could have got away with much lower barriers.

On the other hand, Phoebe the Barred Rock is determined to roost in the highest possible place every evening.  She will jump from one object to the next, using them as steps, until she is well over 6 ft high.

So don't just think about the height of your fences, think about oter objects your chickens can use as stepping-stones to get over the fences.

Oh No!  Please nobody tell Phoebe she has wings!  I don't think she has discovered them yet!