We use about 5-6 nappies a day plus a night nappy, and I wash roughly every 2 days - normally 11 nappies in a wash as that's all my 16l bucket will hold. I keep thinking about buying a bigger nappy bucket so I can wash every 3rd day, but then I'm not sure they would fit in the machine so well. Sometimes if I'm out and about during the day when I'm due to wash I'll wait until I get home with the wetbag and then do those as well, so then it'll be 15-16 nappies, but then I'm starting to run low unless I switch for a pockets day (normally in fitteds).
DD will be going to nursery in September so will be in pockets on three days a week and fitteds when at home with me, I might try and wash less often then as I have enough pockets or fitteds for 2 days of each
We need a new washing machine though and I'm hoping to get one with a bigger capacity. I used to just wash, but I now do a cool rinse, then a 40 wash (60 maybe once a month) and then finish with another rinse, as I found my fitteds were getting a bit whiffy and had to strip them, so I'm trying to avoid that by using the rinses.