Posted: 07/08/2013 at 22:07
I think there are now laws regarding the height of Lleylandi hedges Jade so it may not really solve your problem. Slughunter's suggestion sounds much more pleasant. Could you attach some trellis to your wall if that's suitable? You could use ivy to give all year round privacy and then add some flowering climbers which will grow through it as suggested.
Were you notified of the intended building work so that you had a chance to object? If it's Tesco though, I expect you don't have much chance of beating it!