A summer and a winter cotton duvet, swapped with the seasons
You need two cotton duvets, a light one for the warm months and a heavy one for winter, swapped when the season turns.
Updated .
In short: A light cotton duvet near 200 GSM for summer, a winter one at 450 GSM or more, both wide enough to clear your mattress sides.
| The duvet | Summer duvet | Winter duvet |
|---|---|---|
| Fill weight | The cotton-fill pages cited here give no figure in ounces, so compare the two duvets by GSM. | One cotton-filled full/queen insert lists 11.80 lbs in total (maker spec). |
| GSM | 150 to 250 GSM (quilt weight guide). One all-cotton summer duvet lists 200 GSM (maker spec). | 450 GSM and up (quilt weight guide). One cotton-filled winter insert lists 640 to 680 GSM (maker spec). |
| Construction | Cotton fill stitched into diamond compartments inside a cotton casing (maker spec). | Baffle box. One organic cotton insert uses it to stop the fill shifting (seller page). See the construction types compared. |
| Finished size with overhang | A queen mattress is 60 x 80 in (size chart). One full/queen cotton insert lists 88 x 92 in (seller page). That leaves 14 in on each side, minus your mattress depth. | Same queen bed. One cotton-filled full/queen insert lists 88 x 96 in (maker spec), which also leaves 14 in per side before depth. |
| Washing | Queen: a washer with no agitator and 3.5 cu ft or more (washer size guide). King: at least 4.5 cu ft (Consumer Reports). | The machine sizes are the same. Consumer Reports adds that more room is better (Consumer Reports). |
Weights and sizes come from published maker specifications and textile sources cited on this site. This site weighed and washed nothing.
How your answers set this weight
You said you will change duvets with the seasons, and that choice does most of the work. A cotton duvet kept all year has to sit in the middle, and one bedding weight guide puts an all-season cotton comforter at 300 to 350 GSM. Two duvets take each one out of the middle. The summer duvet can drop to around 200 GSM, and the winter one can go above 450 (quilt weight guide). The summer versus year-round guide explains how different those two weights feel.
Your bedroom temperature decides where the winter duvet sits in its range. One retailer's weight guide puts winter duvets at 450 to 600 GSM or more, and suggests 300 to 450 GSM for bedrooms of 18 to 20°C. A cool bedroom, going by your quiz answer, runs a little below that band, which points the winter duvet at the lower end of the winter range. A cold bedroom calls for the heavy end. In a warm bedroom, the winter duvet may only come out in the coldest weeks.
You sleep alone, or you and your partner run at about the same temperature. That makes one weight per season enough. Your bed size then sets the width. The table works it out for a queen, and the duvet size guide covers the other beds.
Reasons the weight might change
A gap between sleepers changes the answer. If one sleeper runs hot, two separate duvets of different weights may suit the pair better than one shared weight.
The fill matters as much as GSM. GSM alone does not tell the whole story, because different fills insulate differently per gram. Some comforters sold as cotton have a cotton shell over polyester. One light comforter lists 100% cotton fabric over a 100% polyester filling. Read the fill line, as the cotton comforter guide explains.
Your washer can push the choice too. Consumer Reports says a king comforter needs a washer of at least 4.5 cubic feet, so a heavy winter duvet may not fit a standard machine. Where the home machine is small, the large machines at a laundromat make any weight practical to wash. Storage is the price of this answer. One duvet always sits folded in a cupboard while the other is on the bed.
A check under your own covers
Start with a tape measure. Measure your mattress width and depth, subtract the mattress width from the duvet's width, and halve the result. Then take off the depth. The number you end with tells you how far the duvet hangs below the mattress edge on each side. If that figure is near zero, the duvet will lift off as you turn.
On the first warm night, sleep under the summer duvet alone. If you wake hot, your room runs warmer than your quiz answer, so keep the winter duvet back longer. On the first cold night, swap in the winter duvet and notice how your feet and shoulders feel by morning. Cold edges can mean the duvet is too narrow rather than too light.
After a wash, keep drying until the middle is dry, not only the shell. Consumer Reports suggests air-drying a comforter for another hour or two after it comes out of the dryer. The washing guide has the full drying steps.
Other cotton duvet guides
- How much warmer is a year-round comforter than a summer-weight one?
- What does duvet fill weight mean in ounces, and what does each weight do on the bed?
- What size washer does a cotton duvet need, and how do you dry it all the way through?
Back to what weight duvet you need
Sources
Reading list for this cotton duvet piece, each title paired with the section where it does its work.
- maker spec (qbedding.com), at work in the introduction.
- quilt weight guide (sleepsolutions.com.au), at work in “How your answers set this weight”.
- maker spec (linencupboard.co.uk), at work in the introduction.
- seller page (walmart.com), at work in the introduction.
- size chart (mattresswarehouse.com), at work in the introduction.
- seller page (walmart.com), at work in the introduction.
- washer size guide (homedecorbliss.com), at work in the introduction.
- Consumer Reports (consumerreports.org), at work in “Reasons the weight might change”.
- Consumer Reports (consumerreports.org), at work in the introduction.
- bedding weight guide (bedsurehome.com), at work in “How your answers set this weight”.
- weight guide (mattressmiracle.ca), at work in “How your answers set this weight”.
- light comforter (qbedding.com), at work in “Reasons the weight might change”.