Finski - does Finland have the same dramatic fluctuations in temperature (and weather generally) that we have here in Britain ? This is what the OP was referring to - and why I think a shed is a good idea. Not compulsory, of course - but if you already have one (or an empty garage) - then why not use it ?
If we look at averages, then British winters of course are mild compared with Scandinavian countries - but if we look at sudden variations in temperature, then maybe we suffer far more from these, than Finland ?
During the heart of some winters, I have found myself out in the garden in shirt-sleeves on a bright, sunny day, only to be followed within a day or two by day-time temperatures well below zero, and night-time temperatures in double figures below.
British weather is weird - and that's why it's a constant topic of conversation for us. I have known days when we've had bright sunshine, snow and hail, overcast skies and a torrential downpour - all within 24 hrs.
During the winter of 2010, my 50-year old central heating pipes inside the house froze solid when temperatures dropped to minus 20, bringing the ceilings down when they eventually thawed, several weeks later.
But it's not the average winter temperature which is the issue, nor even the absolute temperatures themselves (as this isn't a pi$$ing contest) - it's more the sudden and extreme fluctuations we have that send false signals to all forms of wildlife.
From a recent Daily Mail article:
Temperatures are set to nudged a record breaking 21C from the start of next week as Britain enjoys an Indian summer - but forecasters have warned not to get used to it.
The brief spell of unseasonable warmth could precede a polar plunge, bringing England’s first snow of winter by Friday, according to Meteorologists.
This year is already Britain’s 'strangest-ever' for weather, the Centre for Ecology & Hydrology said, with the worst drought since 1976 followed by the wettest summer for a century.
But the erratic climate has a few more surprises in store in the coming days, delivering a taste of three seasons in a week - as a golden autumnal weekend is being followed by summer and winter snaps.