How to improve your bivvy's insulation
We take a look at how to improve a night's fishing on the bank
1 Use an overwrap
The difference between a single and a double skinned shelter in winter is absolutely massive and the first step towards improving your comfort on the bank in winter! The air trapped between the two layers warms, dramatically increasing the insulation of the bivvy and therefore your warmth within.
What’s more, condensation within the bivvy is completely reduced, meaning you won’t wake-up to a constant stream of drips on a frosty morning or worse still a frozen bivvy. In most cases there’s no need to buy a new bivvy, as most shelters on the market, even ‘open fronted’ summer versions have overwraps or ‘winter skins’ available to buy as an add on item.
2 Use a groundsheet
ust like a second skin over the bivvy, a groundsheet underneath is quite simply a must have item for overnight sessions in winter. The groundsheet insulates the bivvy and the air temperature within it from the freezing temperatures of the ground, which will always be the coldest point inside the bivvy.
Unprotected from the cold temperature escaping from the ground all your other insulations such as clothing and sleeping bag will simply not perform at their full potential. What you’re looking to achieve for maximum warmth inside your shelter is to pretty much build a total cocoon around yourself - complete protection from the elements.
3 Use your kit for insulation
One thing a lot of anglers will do is set-up and then leave things like the unhooking mat and rod bag or sleeves outside the bivvy. Yet these items are great for increasing the insulation of the bivvy. So when dry and not in use, slide these things under the bedchair, which increases insulation, adding extra protection to your body temperature as you sleep, from the ground and coldest area of the bivvy.
In fact any piece of luggage that you can fit under the bed will make a difference towards staying warm and comfortable.
4 Zip-up
Any gap or space within your bivvy that can let cold air in or allow warm air to escape is going to significantly lower the warmth and comfort inside. So when you are inside the bivvy sheltering from the winter conditions zip-up the door using it in a ‘letterbox’ style. Temperature lowering drafts are noticeably reduced, which in turn increases the heat retention of the warmth you’re trying to create with an overwrap etc. Best of all you can still look out onto your swim.
