Why the Duvet Matters as Much as the Mattress
The mattress gets all the attention. Everyone knows to spend on the mattress. But you spend a third of your life under the duvet, not just on the mattress. The quality of what covers you — how well it regulates your temperature, how it moves with you, how much it weighs — has as much influence on sleep quality as the surface you're sleeping on.
A bad duvet is too heavy, traps heat, shifts in the cover creating cold spots, and doesn't move when you turn over without deliberate effort. A good duvet is light for its warmth, breathes, stays distributed and is barely noticeable. You stop thinking about it. That's the goal — a duvet you forget is there.
Down vs Synthetic Fill
Down (the soft under-plumage of waterfowl) and synthetic polyester fill are both used in premium duvets. The difference in performance is significant and honest.
Natural down:
- Warmer for its weight than any synthetic. A 300 g down duvet provides more warmth than a 600 g synthetic duvet of the same size.
- Breathes. Down absorbs moisture and releases it, regulating body temperature passively. You're less likely to overheat at 3 am under down than under synthetic.
- Compresses and recovers. Down compresses when you roll over and springs back to a full, even loft almost immediately. This means no cold spots from redistributed fill.
- Lasts 10–15 years with correct care. A quality down duvet is a ten-year investment, not a two-year replacement cycle.
Synthetic fill:
- Hypoallergenic by design — appropriate for genuine dust mite or down allergies.
- Machine washable at home. Down duvets require professional laundering or very careful home washing.
- Less breathable than down. Warm sleepers often find synthetic fill less comfortable than down.
- Cheaper and easier to replace when worn.
For most people: down. For people with confirmed allergies or a strong preference for easy home care: high-quality synthetic.
Fill Power: The Number That Matters Most
Fill power measures how many cubic inches one ounce of down occupies when it has fully expanded. Higher fill power = larger cluster size = more loft per gram of fill = warmer duvet for less weight.
- 300–400 fill power: standard quality. Functional but heavy for its warmth. Common in budget down products.
- 500–600 fill power: good quality. The practical standard for a duvet that's both warm and comfortable.
- 700–800 fill power: high quality. Light, extremely lofty, very warm. The range used by luxury bedding brands and the one most people feel the difference in.
- 850–900+ fill power: exceptional quality. Polish white goose down at the top of the market. Extraordinarily light for its warmth. The standard in the world's best hotel beds.
When comparing duvets: fill power is more important than total fill weight. A 200 g, 800 fill power duvet is warmer than a 400 g, 400 fill power duvet — and weighs half as much.
Goose Down vs Duck Down
Goose down clusters are larger than duck down clusters, giving higher fill power at equivalent grades. Premium goose down — particularly Hungarian or Polish white goose down — is the top of the down hierarchy. Hungarian goose down from old-breed geese raised in the Pannonian Plain has some of the largest natural down clusters in the world.
Duck down is excellent and perfectly appropriate for most needs; at a comparable fill power, the practical difference in warmth-to-weight ratio is minimal. The price difference between duck and goose at equivalent grades is significant. The performance difference is more relevant at the very top of the quality range.
Tog Ratings Explained
Tog is a measure of thermal resistance — how well the duvet insulates against heat loss. Higher tog = warmer duvet.
- 1–3 tog: summer duvet. Very light, minimal warmth. For warm climates or hot sleepers in summer.
- 4.5 tog: light duvet. Suitable for summer in northern European climates.
- 7.5–9 tog: three-season duvet. Appropriate for spring, summer and autumn in temperate climates.
- 10.5 tog: the most popular standard: a year-round weight that works in most normally heated bedrooms.
- 12–13.5 tog: warm duvet. For cold bedrooms, cold sleepers or winter use.
- 15 tog: heavy winter duvet for very cold conditions or people who sleep cold regardless of room temperature.
All-season duvets combine a 4.5 tog and a 9 tog, buttoned together to produce 13.5 tog in winter or used separately for lighter seasons. Practical and cost-effective; slightly bulkier in storage.
Which Tog Is Right for You
The honest answer depends on three variables: your sleep temperature, your bedroom temperature and your sleep partner's preferences. Couples who have different temperature preferences are one of the strongest arguments for individual duvets rather than a shared king-size.
A simple guide:
- You wake up too hot, push the duvet off, sleep with your feet out: try 7.5 tog. If you're still hot: 4.5 tog.
- You sleep comfortably under a standard duvet year-round: 10.5 tog is your weight.
- You're always cold, wear socks to bed, have a cool bedroom: 13.5–15 tog.
Room temperature matters: a well-heated bedroom (20–22°C) requires a lighter duvet than a cool bedroom (15–17°C) even for the same sleeper.
Duvet Size: Go Larger Than the Bed
A duvet the same size as the bed is too small. It doesn't drape over the sides, which means it slides off the edge when you roll over and leaves cold gaps. Size up.
For a 160 cm (queen) bed: a 200 × 200 cm or 200 × 220 cm duvet. For a 180 cm (king) bed: a 240 × 220 cm or 260 × 220 cm duvet. The extra width hangs over the sides, stays on the bed when you move and looks more generous when the bed is made.
Many European bedding standards offer super-king duvets (260 × 240 cm) for king beds, which provides the most generous drape and suits beds in rooms with high ceilings where a more generous proportion reads correctly.
Duvet Covers and Their Effect on Sleep Temperature
The duvet cover is the final layer between the fill and your skin. It affects both the feel of the duvet and its thermal performance.
Percale cotton (long-staple, tight weave): cool, smooth, crisp. Reduces the apparent warmth of the duvet slightly due to its breathability. The right choice for warm sleepers or warm climates.
Sateen cotton: smoother than percale, slightly warmer because the denser weave reduces breathability. The right choice for those who prefer a softer, warmer feel.
Linen covers: the most breathable and temperature-regulating option. Slightly rougher than cotton initially; softens dramatically after washing. The best choice for people who sleep hot but want a substantial duvet.
Washing and Care
Down duvets can be machine-washed at home in a large drum machine (minimum 8 kg capacity) on a 40°C delicate cycle with a specialist down detergent. Use three clean tennis balls in the drum — they break up the down clumps as it tumbles and prevent the fill from felting into one heavy mass.
Dry on low heat in a tumble dryer for a minimum of two full cycles. The duvet must be completely dry before storage — damp down develops mildew. If in doubt, add another drying cycle.
Professional laundering: recommended every 3–5 years even if you home-wash more frequently. Professional down washing restores loft that home washing doesn't fully recover.
Frequently Asked Questions
- What tog duvet is best for year-round use?
- 10.5 tog is the most versatile single-weight duvet for year-round use in a normally heated European bedroom (18–21°C). In warmer months it can be supplemented with a lighter cover layer rather than replaced entirely. For more flexibility, an all-season two-part duvet (4.5 + 9 = 13.5 tog) provides three configurations from two duvets.
- Is goose down better than duck down?
- At equivalent grades: marginally. Goose down clusters are slightly larger, giving marginally higher fill power. The practical difference at a consumer level is small. The quality of the specific down — cleanliness, cluster integrity, fill power rating — matters more than the species. High-quality duck down at 700 fill power outperforms low-quality goose down at 500 fill power.
- Can I put a down duvet in the washing machine?
- Yes, in a machine with a minimum 8 kg drum and using a specialist down detergent at 40°C on a delicate cycle. The critical step is drying: tumble dry on low heat with tennis balls for two full cycles. The duvet must be completely dry before use or storage. A damp duvet will develop mildew and the down will clump permanently.
- What fill power do I need for a luxury duvet?
- 700–800 fill power is the luxury standard: light, very lofty and warm for its weight. You'll notice the difference between a 500 fill power duvet and a 750 fill power duvet of the same tog immediately when you pick them up. The higher fill power duvet is noticeably lighter and puffs to a much greater loft. This is what makes the difference between a duvet you forget is there and one you feel all night.
Browse our luxury duvet collection and complete your bed with our full bedding range — including linen covers, wool blankets and the pillows your duvet deserves.
