Personally I would suggest removing the little house and instead using something like a log bridge or a cardboard box with the whole bottom cut out and holes punched in the top. The houses are poorly ventilated and they build up condensation which makes it smell bad and drips on the hamster making it damp and smelly.
I would give her some tissue as they need this to build proper nests with. Just carefresh is a bit hard. With plenty ventilation and an open nest she will soon freshen up.
Don't clean every day as they pee more to replace the scent and it is very stressful. We leave as long as possible till the bedding looks tired and loses its spring.
How often do you spot clean or replace your hamster's nest material? I spot clean her sandbath, toys and other accessible areas of the cage every evening.
Only replace at full cage cleans usually around 4-6 weeks. We give extra as it flattens. Spot clear wet area every two days and the rest should be fine.
If cleaning is stressful for your hamster, how long can you leave dirty nest material and substrate?
There is a thread somewhere on how long between cleans and generally people are between 3-6 weeks epending on cage size, substrate depth, species and other factors.
Is having all this hamster feces and urine around safe for humans? I keep my hamster's cage in an open-plan kitchen/dining/living room.
The hard black poo is smell free and inoffensive. Hamsters are desert animals and they draw most of the water out the poo before it is passed. You ca pick it out and dispose if you prefer but we have never found this is needed as it doesn't smell and has never harmed anyone I know of. The wet corner needs the litter removed and we spray with a pet safe stray and then wipe with kitchen roll to dry and replace fresh litter every couple of days. If they use a potty all the better and we use chinchilla SAND and throw this out, wash the potty and replace with clean.
Will a hamster eventually throw dirty bedding and rubbish out of its the nest by itself? She does sometimes kick nest material out - I'm not sure if that's because she thinks it's dirty or whether it's because she just doesn't want that much in her house.
If they don't find if offensive they won't throw it out unless they have too much in there to be comfy. Sometimes they move the whole lot to a new location. We offer fresh stuff when it looks a bit flat to build in to the nest. We always put a little food in the store area after cleaning and also replace a bit of the old bedding to keep the scent and this does help them settle after a clean.
Your hammy should not smell of wee though if the nest is well ventilated though babies sometimes take a while to set up a routine and a potty area.
Hamsters are clean, fastidious little creatures and should pose no health risks to you or your family