How have other people managed with their large families re their housing situations?? Did you extend, move house, upsticks and leave the county, country or continent? For e.g. a friend of mine (with 5 DCs) had to emigrate to France to find a property big enough/afford all of them!
We are in a bind currently with 6 of us in a 3 bed semi-detached and had our planning permission to extend turned down by the council. 3 boys and a girl. Eldest is 14 and he is sharing with his 11 yr old sister which is FAR from ideal. We have bought them a screen so they can have privacy from one another but they want/need their own rooms. Just doesn't sit right to have them sharing when DS is now self-conscious with training bras and the like. Sleepovers are a nightmare! DS3 (5) and DS4 (1) are already sharing the tiniest room of the house so cot and cabin bed in there. DH and I have the biggest bedroom and we're facing putting three boys together in our room and moving next door. BUT with 14, 5 and 1 they have massively different bedtimes/routines and how it will work on a practical level we don't know. 
We can't convert the loft either, our roof is too low -told we need clearance of 2 metres only 1.85. Someone suggested lowering our ceilings to get it done but honestly HOW can we live in a building site with our situation?? DH and I are both self-employed and have our office in the garden so would need find place with an outhouse too - Argh! Kids are all settled at their local schools and BFF's close by as we've lived in same place for 13 years now - they don't want move. Am tearing my hair out as we can't afford to move and we can't go on with current sitch either.
Please share your stories with how you coped with your expanding families! I keep hoping the answer will come to me...