What height sides are safe?

[MandFpiggies]

Given that I have just had a piggie jump over 6 inch coraplast sides without much effort (but with disastrous consequences), and I have just discovered that the same troublemaker can put her head through the squares of my c&c grid:..., I was thinking of either lining halfway up the grids or changing completely to clear perspex. My question is if I'm building sides what height is going to keep my piggie (who may have been Evil Kenevel in a past life) safe??/

 

[Connie]

How old is this trouble maker? And i would say nothing less than the height of the C&C grid

 

[MandFpiggies]

She's around 4/5 months and under 400g, right now she is in a 1x1 cube with coraplast sides to keep her from sticking her head through and breaking her neck while she recovers from surgery to pin the leg she broke by leaping lemming like from the from the upstairs of her c&c cage rolleyes. 14 inches of slippy perspex should keep her in .