There is a particular kind of British evening — usually somewhere between late September and early November, or during one of those spiteful cold snaps in March — when the heating has gone off, the light has faded, and you settle into the sofa with a cuppa only to find your shoulders are cold. The answer is not to fire up the boiler for the whole house. The answer is a throw.

Why a Throw Earns Its Keep

Heating an entire house so that one person can watch television comfortably is an expensive habit, and it dries the air out besides. A throw does the job far more efficiently: it traps a layer of warm air close to your body, so you feel noticeably warmer within a minute or two of pulling it over your knees.

The trick is to have the right throw in the right place. A heavy wool blanket that lives on the sofa is no use folded at the end of a bed, and a lightweight cotton blanket will not keep you warm through a draughty evening in February. Think in layers, and think about where each one will be used.

Wool Throws: The Sofa Workhorse

For the living room, wool is hard to beat. It is naturally temperature-regulating, so it warms you without turning clammy, and it holds its shape through years of being folded, dragged about and sat on. A pure wool throw also resists creasing and smells fresh for longer than you might expect.

Look for a tight weave — twill, herringbone or a firm basket weave. Loose, open weaves look lovely in photographs but snag on rings, buttons and cat claws within a fortnight. Check the finishing on the edges too: a properly whipstitched or hand-tied fringe will survive repeated washing, whereas a loose one will unravel by spring.

Weight matters more than most people realise. A mid-weight throw of around 400 to 600 gsm is ideal for indoor use — substantial enough to feel like something, light enough to drape over your shoulders without sliding off. Lambswool gives you softness without the prickle of coarser fleece, and merino is softer still, though it tends to cost more.

As a rule of thumb, a 130 x 170 cm throw covers one person on an armchair or sofa seat. If two of you regularly share, go up to 150 x 200 cm or larger, and accept that the person who gets up for the biscuits will let the cold air in.

Cotton Blankets for the Bedroom

Beds are where cotton earns its place. Wool is wonderful on a sofa, but it can feel heavy and over-warm overnight, particularly in centrally heated houses. Cotton breathes, absorbs a little moisture and can be washed frequently — an obvious advantage on a bed.

A waffle-weave or cellular cotton blanket is the most useful thing you can put on a bed. Cellular blankets trap air in their little pockets and give warmth without weight. Waffle blankets are slightly denser and look good left on show.

Sizing is where most people go wrong. A blanket that is too small will not stay tucked and will slide off during the night. For full coverage of a double bed, look for something at least 200 x 230 cm. A 150 x 200 cm blanket works beautifully laid across the foot of the bed, ready to pull up if the temperature drops at three in the morning. Buy one per bed — being woken by a cold, blanketless partner is a poor way to start the day.

A Quick Sizing and Weight Guide

• Sofa or armchair throw: 130 x 170 cm, 400–600 gsm wool
• Throw for two: 150 x 200 cm or larger
• Across the foot of a bed: 150 x 200 cm cotton
• Full bed coverage (double): 200 x 230 cm or larger
• Spring and autumn nights: 250–400 gsm cotton over the duvet
• Deep winter: wool blanket between sheet and duvet, cotton on top

Layering a cotton blanket between the bottom sheet and the duvet is a much underrated trick. It adds real warmth, can be peeled off at two in the morning without disturbing anyone, and costs far less than a new, higher-tog duvet.

Washing and Care

Wool should be washed rarely. A good airing over a banister or a line on a dry, breezy day will freshen it more often than not. When it does need a clean, use a wool cycle at 30°C with a gentle detergent, then dry it flat and away from direct heat. Never tumble dry wool unless the label explicitly says otherwise. Store it in a breathable cotton bag with a few cedar blocks or a lavender sachet, and check it once a season for moths.

Cotton is far more forgiving. A 40°C machine wash, a low tumble and it is back on the bed the same afternoon. Expect cotton blankets and waffle throws to soften with every wash, which is one of the reasons they become favourites.

Shake throws out weekly rather than washing them. It redistributes the fibres, releases dust and keeps them looking plump.

Building a Sensible Collection

You do not need a linen cupboard full of blankets. Four pieces will see most homes through the year comfortably: one wool throw on the sofa, one lightweight cotton blanket per bed, and a spare mid-weight throw kept folded in a basket or the airing cupboard for guests, picnics and power cuts.

Rotate them with the seasons. Wool comes out in October and goes away in April; cotton stays on the beds year round and moves to the sofa in summer. Treated well, a decent wool throw will last a decade or more, softening and improving as it goes — which is exactly what you want from something you reach for every chilly evening.