My grandfather owned exactly one winter coat. It was navy, double-breasted and cut from a wool so dense that it could stand upright, briefly, when he dropped it on the hallway floor. He bought it during his first London winter, having arrived from Kumasi in a lightweight suit and been warned by a colleague that he would not survive January. He wore it for thirty-eight years. When he died, it went to my father, and now it hangs in my wardrobe.

I think about that coat whenever I see the modern alternatives: the technical puffer, the bonded shell, the fleece-lined parka with its dozen zipped pockets. They are lighter, warmer per gram and more practical in almost every measurable way. They are also, for the most part, designed to be replaced. Their membranes delaminate, their down clumps, their zips fail, and they rarely look better after five years than they did on the first day.

The argument for weight

The heavy coat works on a different principle. A proper overcoating, typically between seven and nine hundred grams per metre, keeps you warm through sheer mass: tightly woven fibre that traps air and blocks wind. It sits heavy on the shoulders in a way that feels, after a while, less like a burden than an embrace. It also changes how you walk. You cannot hurry in a coat like that, and it is surprising how rarely you need to.

Few mills still weave cloth of this weight. One of them, Brannock Mill in the hills above Huddersfield, has produced it continuously since the eighteen-nineties. Its owner, Ruth Pendleford, told me that orders for heavyweight overcoating have doubled in three years, largely from small tailors and independent labels. The customers are younger than she expected, and almost all of them ask the same question: how long will it last?

Heavy cloth is an act of faith. You are betting that someone will still want it when they are old. — Ruth Pendleford

The answer, with basic care, is longer than you will. Good wool resists odour, shrugs off light rain and recovers from creasing overnight on a hanger. Moths are a risk, but cedar and regular wear deter them. A heavy coat can be relined, rebuttoned and even turned, the old practice of unpicking a garment and rebuilding it with the unfaded inner face outward. My grandfather's coat has been relined twice. The cloth has barely changed.

None of this is an argument against technical outerwear, which has its place on mountains and bicycles. It is an argument for owning at least one garment that asks something of you: that you brush it, hang it properly and accept its weight. In return it offers a kind of armour, and a dignity that no amount of lightweight insulation has yet managed to replicate.

This winter I will wear the navy coat again, as I have every winter since it came to me. The shoulders are a touch wide for current taste, and the collar has softened into something my grandfather would not recognise. But it still stands up, briefly, when I drop it on the floor, and that small act of stubbornness seems to me the whole point of good clothes.