A bivvy bag turns any sleeping bag into a shelter. We compare the fabrics, waterproof ratings and weights of the bivis UK wild campers actually buy.
9 products, lightest first
6 photosUltralight#1Alpkit
A 285 g, 3-layer bivvy rated 20,000 mm waterproof and 30,000 g/m² breathable.
From
£159.99
at Alpkit
6 photosBest value#2Alpkit
The UK wild-camping default: 10,000 mm, taped seams, 330 g, under £60.
From
£54.99
at Alpkit
Cheapest#3Mountain Warehouse
The £25 way to try bivvying before you commit to a serious bag.
From
£24.99
at Mountain Warehouse
4 photosBest with a zip#4Snugpak
Military-spec Paratex bivvi with a half-length zip and almost no condensation.
From
£96.95
at Military Kit
Lightest premium#5Rab
A 440 g Pertex Shield Air bivi with a bathtub floor for alpine and bothy nights.
From
£249.99
at Ultralight Outdoor Gear
Roomy cut#6Rab
A 547 g zipped bivi with a 10,000 mm head and 10,000 g/m² breathability, cut for bulky bags.
From
£108.95
at Cotswold Outdoor
Best hooped#7Rab
A hooped, freestanding bivi with a midge door that feels like a tiny tent.
From
£339.99
at Ultralight Outdoor Gear
11 photosHooped bivvy#8Alpkit
A free-standing hooped bivvy: 900 g, two alloy poles, 10,000 mm outer and side-zip entry.
From
£109.99
at Alpkit
9 photosBivvy-tent hybrid#9Snugpak
A hooped bivi shelter with a 5,000 mm fly, 8,000 mm bathtub floor and mosquito net, 1.13 kg.
From
£127.46
at Trekitt
Weights and sizes are manufacturer figures. Prices were checked on 31 October 2026 and change daily, so confirm on the retailer's site.
A non-breathable bivvy keeps rain out and sweat in. Expect a damp sleeping bag by morning. Breathable laminates such as Gore-Tex or Pertex Shield cost more and weigh a little more, but they are the difference between a bivvy you use and one you avoid.
The height of a water column the fabric resists before leaking. 10,000 mm or more is genuinely waterproof for ground contact; 3,000 mm will cope with light rain and dew.
A winter down bag lofts to a large diameter. Compressing it in a tight bivvy kills its warmth, so check the bivvy's girth against your sleeping bag.
A single hoop keeps the fabric off your face and makes a wet night far more bearable, at the cost of 200 to 400 g and a pole to carry.
Methodology
Specs are manufacturer figures, or a UK specialist retailer's spec sheet where the maker is vague. Prices were checked on 31 October 2026. Our ratings are editorial and explained on the how we test page.
