I haven't done a lot of festivals, but in my experience, singers do tend to get squeezed out where venues are limited (I speak as a singer and also an instrumentalist, so I can change horses as required). The main singing events at festivals - this is a bit of a generalisation - tend to be either noisy bar-room free-for-alls where lusty choruses win the day, or folk-club-style events in an upstairs room somewhere, which can be as good or as bad as those attending them.

You might want to consider one of the specialist singers' events held around the country. Maddy Prior runs some in the Borders (google for Stones Barn). Folkworks may have something suitable in north-east England, although I don't think they're residential, you'd need to find accommodation. Halsway Manor in Somerset run some interesting-looking residential singers' weekends, one of which a friend and I are booked in for later this year. But you'd need to get leave of absence from home, and anything residential is not cheap.

I hope someone can suggest a festival that ticks the boxes for you. The main problem may be accommodation, as many festival venues don't have enough B&B to meet the demand. If you're prepared to drive a bit at the end of the day, this gives you a wider choice of places to stay, but if you like to drink, this makes it trickier.The good thing about a festival is that you can take the family and they'll probably find something to entertain them, but you all have to find somewhere to stay.

I'll watch this thread with interest as we've recently sold our camper van and are now restricted to events where there's B&B or simlar placse to stay.

Marje