Bivy sack is the short form for the words ‘bivouac sack’. It was created to help backpackers and climbers who need emergency – and lightweight – weather protection for sleeping bags when they are involved in multiple-day ascents, especially on big walls. The bivy sacks that were made in the early days, can just be described as waterproof nylon slipcovers for sleeping bags. They were just good enough to shield sleeping bags from rain or snow but were not good at ventilating vapour that was produced by the body heat of the user.
At the moment, bivy designs now involve 2 tiers of fabric:
- The top tier is normally made using ripstop nylon – which is a light fabric – and is treated with a breathable and waterproof laminate such as Gore-Tex.
- The bottom tier typically consists of a durable type of nylon that is coated with urethane to ensure that it is waterproof. This is the same material that is used for a lot of tent floors.
The Mountain Warehouse Bivvy Bag
The typical bivy bags are lightweight, waterproof, small and an effective alternative to the heavy and bulky tents that backpackers, hitchhikers and climbers carry on their sojourns. There are different brands of bivy bags that are available on the market. However, we recommend the Mountain Warehouse Bivvy Bag due to the extra insulation it can provide when it is used in conjunction with a sleeping bag.
In addition to this, the waterproof nature of this bivy will prevent rain or dampness from entering into the bivy. Even with this waterproof design, the bag is also breathable. The Mountain Warehouse Bivvy Bag also comes in a compact bag that users can use to store the bag when they’re not making use of it.
For an additional pound or thereabouts, a tent-esque bivy shelter will add two features that are not available in the traditional bivies. These features are a full enclosure meant to block out insects and bad weather; and an expanded area of shielded headspace. These extra features have contributed to the growth and popularity of bivy shelters, particularly with ultralight hikers.
You might be overwhelmed with the different sizes, styles, colours and shapes of the Mountain Warehouse Bivvy backpacks. However, there are packs that will suit your particular needs – be it a normal outdoor activity or a biking or backpacking trip that only comes once in a lifetime. The goal is to narrow down your search to the particular piece that actually suits your need. The size of this particular model stands at 225 cm x 75 cm and it weighs a bare 340 g – making it very convenient for users to take it along with them for biking and hiking trips.
The seams of this bag are taped to provide extra protection. What this means is that when you make use of this waterproof bivy as a lining to your regular sleeping bag, you’ll get greater warmth, while also keeping insects and other elements of nature at bay. It should be noted that a bivy bag can improve a sleeping bag’s effective temperature range by as much as 5F.
Pros and Cons of the Mountain Warehouse Bivvy Bag
The biggest pros and cons of this bivy are:
- Compact: The Bivvy bag is just 225cm x 75 cm, which makes it very small and convenient to roll and store.
- Lightweight: It weighs a mere 340 g, meaning it is ideal to carry with any kind of camping gear.
- Waterproof: The use of ripstop nylon and the presence of a waterproof membrane ensure that water and the morning dew are kept from seeping in – thereby ensuring that the bag is dry.
- Sleep anywhere: Since the bivy is so compact and small, it can be used anywhere – be it a small clearing, a ledge or even in the harness during mountain climbing.
- Restricted space: Unlike in a tent, there isn’t enough space in the bivy for users to change positions while sleeping.
- Absence of rain protection: Though the bivy is waterproof, it does not offer protection to the face when it rains. The only option left is for the user to sleep on his/her stomach to prevent getting wet.
- Thin material: The material is quite thin and the odds of a tear when in the wild or on uneven surfaces are high.
- Waterproof & taped seams – The rainproof design of this bivy bag prevents water from getting in.
- Ripstop – Stops rips, heavy-duty fabric and ensures the bag lasts longer.
- Alternative use – Can be used as a protective cover.
- Dimensions – 225cm x 75cm, weight – 340g for convenience.
- Stuff sack – Compact & portable tent accessory.
If biking and camping is a way of life, you will certainly need a gear that is weather-resistant, compact, durable, portable and also lightweight. So before you decide to get a bivy bag, you should consider the weather, the terrain and the weight you will need to carry during your journey. You should also consider your sleeping posture and sleeping habit before deciding on a bivy to get.
Reviewing this Mountain Warehouse Bivvy Bag proves that it is a pretty decent buy – for any backpacker – due to its waterproof feature, taped seams and its ripstop fabric. It is also lightweight and comfortable. So, for your hiking or biking trip, the Mountain Warehouse Bivvy Bag can be effectively used.
In addition to all these, the bag comes with a stuff bag which makes it portable and compact. Though there are concerns about the fabric’s breathability, this bivy can be used for the occasional forays out in the open.
Users of this Mountain Warehouse bivy bag have found that it is convenient and compact to use for a nightstand. However, they say it is not breathable as is claimed by the manufacturer. It can be a great buy for good weather conditions, but it isn’t ideal for severe weather conditions. It isn’t as durable as other bivy bags, but for the price it goes for, it is worth it.