The UK is damp, and it's cool, it's not cold. There's a massive difference between island and continental.
Scandinavian style houses are just as damp here as any other. Insulation is brilliant, but it needs to be balanced with airflow.
I have a friend who lives in a yurt full time here in South Lanarkshire. She owns an acre of land that she uses as a smallholding.
The yurt is on a permanent wooden base raised off the ground and with air flow beneath it. Otherwise the damp soaks in. No airflow and the mould grows. The yurt needs to be pretty much permanently heated here (and no, it doesn't take 'five cords' of wood to do it; we burn hardwoods here, not pine which is crap firewood) except in the height of Summer. The stove heats the house, but it's build into a clay and tile heat mass that absorbs heat from the stove and the flue and slowly gives it off as a kind of central heating.
Plumbing is one pipe (off the mains water supply) up into a wally sink, drainage from that goes to a small reed bed soak away that waters fruit trees. The loo is a wooden structure on the same wooden platform, but outside the yurt. It's a composting toilet, with sawdust and peat dust as the soak up medium.
There are huge issues disposing of such material in such a small area. It needs a lot of rotting down before human fecal bacteria is considered to be 'dead'….look up
http://www.eco-toilets.co.uk/faq-storage-and-composting/
and needs to be kept on site for at least half a year….after it's 'composted'.
It's actually easier to have a long drop loo, but she couldn't do that right next to the yurt, and since she's getting older and finds that she gets up at least once in the night for a piddle, didn't want it too far from her warm home.
There is potentially connection to the mains sewerage just a couple of hundred metres away from her yurt, but it's expensive to dig the trench, supply the pipe, and get hooked up…..community charges are paid anyway, so no extra fees really. I believe that it's on the books to do the hook up and just have a normal loo, but 'flush' it with a bucket of water and a jug, but the septic tank is more usual and would actually be easier to do. It's a question just now of which route she wishes to go. I think the septic tank will win out, but it's expensive.
Damp is the one constant issue, unless the stove is lit.
She has two cats, and they keep the vermin away/hunt them down.
Airflow/ ventilation is a necessity of life. Get the balance right and it's a very comfortable home.
Planning permission was applied for, and granted, the biggest issue was sewerage but she's dealing with that. That she lives alone means that there's not a lot of it to deal with anyway, but a family might be a very different matter.
Didicoy's comments are very relevant. My friend was fortunate to be part of a site which already embraced the ethos, so to speak, and the planning officers treated the yurt as a 'static caravan being used as a agricultural dwelling' because she lived on her one acre small holding.
I have two other friends who have yurts. Both are set up on permanent wooden platforms, but since neither has planning permission as full time dwellings or holiday homes, they dismantle their yurts once a year, and lay them down for a month.
They take the time to clean the platform, true up the frames, reproof the roof cloths, etc., In a wet summer it's not a fun job though.
All latter two yurts are made of wool felt (the ladies are felt makers) and are warm, and much easier dealt with re mould and damp than the canvas ones. They are however in need of constant vigilance re moths and insect infestations. Neither lady wants everything drenched in insecticides, and generally go for the organic alternatives, the permithrin plant based dusts and the like.
Living in a yurt can be a lovely home, but it needs constant attention. It's drier than living in a caravan in our climate though, mostly because of the airflow and the stoves that deal with the condensation issues.
On balance a small wooden cabin would be a much better solution. The ones sold as holiday chalets do make very comfortable homes, but trying to get planning permission for such is not always easy since they are permanent residences.
Condensation and damp are permanent issues here. I live in a modern centrally heated home. It's well insulated, double glazed, etc., and I've just opened the blinds, and lo and behold, there's condensation on the windows. We have no heating on yet (the thermometer in the kitchen is reading 17.6 this morning, but 7.9 outside, we aim for around 20 in Winter and in the evenings. Daytime I'm in and out all the time and the back door is mostly left open, so no point heating the great outdoors) though, so I'll just open the windows a little bit and let it air out through the morning. The heating will go on full time in a couple of weeks and that stops the condensation since it drives the air exchange that shifts the moisture.
Get it wrong and mould grows. It's just a fact of life. Dehumidifiers are a win/win for our climate. They take out moisture and they give out heat as they do so.
I'm told that if you build a base platform on short piles, but fill in with shingle to close under the floor platform, that the stone mass cuts the draught but allows airflow and acts as a kind of heat mass too. I don't actually know anyone who is doing that though.
cheers.
Toddy