The short answer: choosing a duvet starts with your bedroom temperature and whether you usually sleep too warm or too cold. Those two things decide the filling (down, synthetic, sheep's wool or alpaca) and how much of it you need. Then you pick a size, by your height for a duvet of your own or by the mattress width for a shared one, and check that the care routine suits your home, for example whether an allergy means the duvet has to be washed at 60°C.
I run UNWONTED, a duvet brand that uses fleece from Polish alpacas, so I am writing as someone who sells one of the materials described here. That is why this guide also covers the situations where an alpaca duvet is not the best choice.
1. Check how warm your bedroom is
A commonly recommended bedroom temperature for sleep is around 16–19°C (60–67°F). A centrally heated flat can be warmer than that in winter, and a house where the radiators are turned down at night or the window is left open will be noticeably cooler. A thermometer in the bedroom for a few nights will tell you more than any label.
- Heated bedroom, above about 19°C: choose a lighter duvet with a filling that takes up moisture well.
- Bedroom at 16–19°C: a medium-warmth, all-season duvet is enough.
- Bedroom below 16°C, or you feel cold even under a thick duvet: choose a winter duvet.
The second question is how you sleep. People who sweat at night are more often woken by dampness under the duvet than by the temperature itself. For them, what matters more than thickness is whether the filling absorbs water vapour or leaves it next to the skin.
2. Choose the filling
Most people choose between four fillings, and each suits a different sleeper.
| Filling | Strength | Weakness | Best for |
|---|---|---|---|
| Down | Lightest for the warmth it gives, very lofty | Needs long, thorough drying after washing; large duvets are best taken to a laundry | Cold sleepers who like a light, high duvet |
| Synthetic (polyester fibre) | Lowest price, usually washable at 60°C | Polyester absorbs almost no moisture, so sweat stays between the fibres | Allergy sufferers told to hot-wash bedding, guest rooms |
| Sheep's wool | Absorbs moisture well, costs less than alpaca | Contains more lanolin, which some people react to | People who want a natural filling on a moderate budget |
| Alpaca | Absorbs water vapour and releases it gradually; little grease (lanolin) compared with sheep's wool | Heavier than down, more expensive, cannot be washed in hot water | People who sweat at night or wake up alternately too warm and too cold |
A fuller comparison, with figures on moisture, weight and care, is in Alpaca, down or synthetic duvet? The differences explained.
3. Choose the warmth, or fill weight
Fill weight tells you how many grams of filling there are per square metre of duvet. Compare it only between duvets with the same filling, because different fillings give different warmth for the same weight, and down gives the most warmth per gram.
Our duvets come in two fill weights: the lighter all-season at 400 g/m² for heated bedrooms, and winter at 600 g/m² for rooms cooler than about 16°C. An all-season duvet of 160×200 cm therefore holds about 1.3 kg of alpaca fleece, and the winter version in the same size about 1.9 kg. How to choose between them is covered in All-season or winter duvet? How to choose the right fill weight.
UNWONTED alpaca duvet
100% Polish alpaca fleece in a GOTS organic cotton shell. All-season 400 g/m² or winter 600 g/m², six sizes from 70×100 to 240×220 cm.
4. Choose the size: your own duvet or a shared one
A duvet of your own is chosen by your height: 140×200 cm suits most people up to about 180 cm tall, and taller people are better off with a 220 cm length. A duvet shared by two is chosen by the mattress, so that it hangs 20–30 cm over each side; on a 160×200 cm bed that means 200×220 cm. Both tables, with advice on covers, are in Duvet size guide: matching your duvet to your bed and cover.
5. Check the care routine, especially if you have allergies
For house dust mite allergy, hospital guidance recommends washing bedding, duvets included, at 60°C, or using breathable, fully enclosing anti-allergy covers. Alpaca and sheep's wool duvets cannot be washed in hot water. If your doctor has told you to wash your duvet at 60°C, a synthetic duvet will be more practical; if you prefer a natural filling, combine it with an anti-allergy cover.
Our alpaca duvet needs regular airing, a duvet cover at all times and spot cleaning when needed. It should not be washed in hot water, tumble dried or dry cleaned.
6. Set a budget
Synthetic duvets are the cheapest; high-quality down and alpaca duvets cost the most. Within alpaca the range is wide, and the difference comes mostly from how much filling there is and whether it is pure alpaca or a blend. What goes into the price is explained in Why does an alpaca duvet cost more?
When alpaca suits you, and when something else is better
An alpaca duvet is a good choice if:
- you sweat at night or wake up alternately too warm and too cold,
- you want a natural fibre filling and want to know where it comes from,
- you like a duvet that drapes over you and is clearly heavier than down.
Choose a different duvet if:
- you want the lightest possible duvet (down),
- your doctor has told you to wash your duvet at 60°C (synthetic),
- you want a natural fibre on a tighter budget (sheep's wool),
- you need a guest-room duvet that will be washed often (synthetic).
Where our fleece comes from
During the May shearing.
Every May we spend six weeks driving from Suwałki in north-eastern Poland to the Tatra Mountains in the south, shearing alpacas on small farms. Klaudia and Andrzej do the shearing, and we sort every fleece by hand afterwards: the finest fibre from the back and sides goes into duvets, and the coarser fibre from the legs and neck is set aside. A small farm collects between 15 and 90 kg of fleece a year, while industrial mills accept batches of 500 kg or more, so without pooling fleece from many farms it would stay in bags for years.
We make our duvets once a year, from a single spring shearing, in a shell of GOTS-certified organic cotton. If this guide has helped you settle on a warmth and size, you can choose your alpaca duvet in the right size.