Most duvet cover comparisons are written for houses with a tumble dryer and central heating. Neither applies here. In a Spanish flat the cover has to survive August without making you hot. It also has to come off a drying rack looking acceptable, because there is no dryer to soften it.
That changes the ranking. Here are four weaves we stock, judged on those two conditions.
Percale: the crisp one
Percale is a tightly woven fabric, firmer and smoother than a standard weave, and it is the most durable of the four. It is woven from long-staple cotton and stays cool. It is the usual recommendation for warm months.
On a rack it dries quickly and hangs flat. The honest downside is that it creases, and percale creases look like creases rather than texture. If you iron nothing, this is the cover people notice.
Duvet Cover Basic Percale, 35.99 euros.
Muslin: the soft one that hides everything

Muslin is loosely woven, and that loose structure is exactly why it breathes so well and conducts heat away. It is the most comfortable of the four in real heat.
It is also the most forgiving on a drying rack. Muslin's slightly crinkled surface is the point, so it never needs ironing. The trade-off is durability: a loose weave snags more easily and can develop holes sooner than a tighter one, and high heat in the wash breaks down those fibres faster. Wash cool.
Duvet Cover Lark Muslin in Eucalyptus, 104.01 euros.
Waffle: texture, and a longer wait

Waffle holds air in its grid, which reads as warmth rather than coolness. It suits the shoulder months and the winter, not August. It is also the slowest to dry on a rack because the weave holds water in every cell.
Buy it as the second cover, not the first.
Duvet Cover Chunky Waffle in Linen, 121.35 euros.
Plain cotton: the one to buy two of
The Duvet Cover Basic Olive Green is 35.99 euros and does the unglamorous job of being the second cover, so the bed is never stripped for a day waiting on a wash. With no dryer, owning two covers is not a luxury, it is the difference between making the bed and not.
What we would actually do
One percale and one plain cotton for the summer rotation, at 71.98 euros for the pair. Add a waffle in October if you want the weight. Muslin if the crispness of percale is the thing you dislike about hotel bedding, and you accept a shorter life in exchange for the hand.
Whichever you choose, pair it with a Fitted Sheet Basic White and an Pillowcase Oxford Grey rather than buying a matched set you cannot break up.

