How Much Does a Wool Sleeping Bag Weigh? (And Why It’s Worth It)

How much does a wool sleeping bag weigh? Ours weigh from 4 lb to 15 lb depending on the bag, the size and the loft, and the one you would carry — the Rewilder in Standard 2″ loft, field rated 20°F — is 4 lb / 1.8 kg. That is about three times a 20°F down quilt. This article gives every number, explains where the weight comes from, does the carry arithmetic for a real pack, shows what you can drop elsewhere, and says plainly who should not buy one.

Wool sleeping bag weight: every Lucky Sheep bag, size and loft

Product	Loft / field rating	Size	Weight	Packed
Rewilder (backpacking, tapered)	2″ / 20°F	Standard (to 6′), Medium 56″ girth	4 lb / 1.8 kg	About 11 × 11 in with straps
Rewilder	2″ / 20°F	Long (to 6′4″) or Wide 66″ girth	Heavier than Standard; between 4 and 5.5 lb	Slightly larger
Rewilder	3″ / 10°F	Standard to Long Wide	Up to about 5.5 lb / 2.5 kg	Larger
Aurora Borealis (rectangular, basecamp)	2″ / 20°F	Single	About 7 lb	Not for carrying
Aurora Borealis	3″ / 10°F	Single	About 10 lb	Not for carrying
Aurora Borealis	5″ / −5°F	Single	About 15 lb	Not for carrying
Merino liner	Adds about 10°F; summer bag alone	28″ or 33″ girth	30 oz / 0.85 kg	Small
Wool felt bedroll	Blanket, over-quilt, pad	50 × 76 in	4 lb	Rolled
Wool sleeping pad	¼ in felt	24 × 76 in	32 oz / 0.9 kg	About 6 × 12 × 12 in

Exact weights for each Rewilder size and loft combination are on the product page; the range above is honest about the fact that a Long Wide 3″ is a much bigger bag than a Standard 2″. Wool weights are also less stable than nylon-and-down weights, because wool holds 13–16 % of its weight in water at ordinary humidity. A bag weighed in a dry room and a bag weighed after a foggy night are not the same weight.

Where the weight comes from

Wool batting against down fill power

Insulation is trapped air, and the question is how much fibre it takes to hold a given thickness of air still. Goose down is the answer to that question: a high fill-power down holds two inches of loft with a very small mass of clusters, which is why a 20°F down quilt can weigh under a pound and a half. Wool batting holds the same two inches with far more fibre — a dense, crimped mat rather than a cloud of clusters — so the insulation alone weighs several times what the down does. That density is also what lets the batting keep its loft when damp, hold water inside the fibre and recover from compression for decades; the weight and the wet performance are the same property seen from two sides.

Cotton shell against 10-denier nylon

The second contributor is the shell. Ultralight bags are shelled in 7- to 20-denier nylon at well under an ounce per square yard, with a DWR finish. The Rewilder’s shell is beeswax-treated organic cotton at several ounces per square yard, and the liner is merino jersey or WeatherWool® worsted rather than more nylon. Over the area of a sleeping bag, the shell and liner alone can account for a pound or more of the difference. What that buys is a shell that breathes, sheds dew, is silent, is not cold to touch, can be re-waxed and sewn, and carries no PFAS or DWR. The zipper is the one synthetic part of the bag.

The carry arithmetic

Base weight is everything in the pack except food, water and fuel. Ultralight is usually taken to mean under 10 lb, lightweight under 20 lb, and a traditional load 25–35 lb. Put a Rewilder into each.

Sleep and carry system	Down and nylon, typical	Lucky Sheep wool and canvas
20°F bag	1.4 lb (down quilt)	4.0 lb (Rewilder Standard 2″)
Stuff sack	1–2 oz	0 (compression straps included)
Pad	1.0 lb (inflatable) plus patch kit	2.0 lb (¼ in wool felt)
Liner	Often none, or 6 oz silk	30 oz merino (optional; adds about 10°F)
Pack (65 L class)	2.0–3.5 lb, framed	2.0 lb (frameless canvas; pad is the frame)
Subtotal, no liner	About 4.5–6 lb	About 8 lb

So the honest difference, bag plus pad plus pack, is on the order of 2–3.5 lb before the liner. For a 25 lb traditional base weight that is a 10 % change and you will not feel it on the second morning. For a 9 lb ultralight base weight it is a 30 % change and you will feel it in the first mile. That is the whole decision: the same 3 lb is trivial in one pack and decisive in another.

What you can drop elsewhere

• The stuff sack. The Rewilder ships with compression straps and no sack. It goes into the 65 L canvas pack loose, fills the corners, and breathes on the walk.
• The pack frame. The canvas pack is frameless and uses the folded wool pad as its frame. You carry the pad anyway; the aluminium stays and framesheet in a conventional pack are 8–16 oz you do not.
• The pad patch kit and pump sack. Felt does not puncture.
• A layer. Because the wool system handles moisture, most people carry one merino base layer for sleeping and one for walking instead of a rotation of synthetic tops that need drying, and the bag opened flat is the camp blanket, so the second puffy stays at home.
• The bivy. The beeswax cotton shell sheds dew and condensation; a waterproof bivy over a wool bag is unnecessary and counter-productive.
• The spare bag in ten years. Not a pack-weight saving, but a real one: wool batting recovers loft after compression year after year, the shell is re-waxable and the bag carries a lifetime workmanship guarantee.

What the pounds buy

The reason to carry 4 lb instead of 1.4 lb is what happens on the second and third nights out in damp country. Wool takes water vapour into the fibre and keeps its loft; down collapses when damp. Wool releases heat as it takes up moisture (about 960 kJ per kilogram of water absorbed); polyester and down release nothing worth measuring. The cotton shell and merino liner are never clammy or cold to touch; nylon is both. Continuous batting has no baffle seams and nothing to migrate to the foot end. And the bag is quiet, repairable and expected to last decades. The full comparison, with synthetic as the third option, is in Wool vs down sleeping bags; the physics is in How wool stays warm when wet.

Who should not buy a wool sleeping bag

Thru-hikers on a five-month schedule, fastpackers, anyone working to a sub-10 lb base weight, alpinists carrying the bag on a climb, and anyone whose pack is under about 50 L. For all of these the extra 2.6 lb and the 11-inch packed size are the wrong trade and a 20°F down quilt is the correct answer. We would rather say that than sell you a bag you resent by the second week. If you are in that group, the merino liner (30 oz) is the one piece of our system that still makes sense inside a down bag; it puts wool at the skin where the clamminess starts and adds about 10°F.

How to decide

1. Weigh your current base weight. Under 12 lb: stay with down. Over 18 lb: the wool bag is a rounding error. In between: keep reading.
2. Count your damp nights. If most of your trips are in the eastern US, the UK, the Pacific Northwest or anywhere with fog, dew and rain at 30–50°F, the wet performance is worth the pounds. If they are in dry cold, it is not.
3. Check the pack. You need a 60 L-plus pack with a wide opening. The Rewilder does not go into a 40 L pack with a bear canister.
4. Decide on loft. 2″ (20°F, 4 lb) for three seasons; 3″ (10°F, up to about 5.5 lb) if your winter trips are real. A liner adds about 10°F to either for 30 oz.
5. Use the finder. The sleep-system finder asks five questions and recommends a bag, liner and pad. The free sample packet lets you feel the batting and shell first.

Sleeping bags and the bedroll are made in Burnsville, North Carolina, from US wool batting, and ship in 2–5 days. Lucky Sheep temperature figures are field ratings, not ISO 23537-1 results; Sleeping bag temperature ratings explained covers how to read them.

Reviewed August 2026. Lucky Sheep weights are as listed on the product pages; down, synthetic and pack figures are typical of current products, not test results; base-weight categories follow common backpacking usage.