In reply to G1STQ:
No-one else seems to have mentioned it so I will. In my experience wicking tops are perfect and don’t need to be expensive to be effective. In most conditions I am comfortable whilst moving wearing a wicking base layer and wind proof layer.
In warmer weather I have t-shirt style wicking top, I’ve tried a fair few different brands and my favourites are actually the cheapest at £5 each from Millets. For cooler weather and very sunny weather (to stop sunburn) I have a looser fitting long sleeve top that has a neck zip, which is handy for regulating temperature and for the days when it’s windy and snowy I have a long sleeve merino wool top that is close fitting, I boil if I wear it on the wrong days though, that was a bit pricey at about £30.
Whilst activating you’ll want something between your base layer and your windproof layer. A long sleeve fleece top seems to be what most people uses. Because you’re going to put a windproof over the top it’s not necessary to get a windproof fleece. You can spend whatever you want on a fleece from £5 in sales up to £200 for very fancy ones. I’m fairly sure it’s better to get a cheaper one especially as that wicking top will be pushing all your sweat into it so it’ll get pretty stinky before too long.
The vast majority of your heat loss will be due to the wind, the waterproof you have is probably an effective wind stopper, so don’t worry about replacing that unless it isn’t “breathable”. You may find that putting on waterproof over-trousers while you’re operating will help you retain heat too. Breath-ability is important otherwise all the dampness coming off your body gets trapped inside your waterproof/windproof. Gore-tex seems to be every manufacturer’s solution to the breath-ability problem. Some waterproofs have under arm zips that can be opened to let the air flow a bit more, which surprisingly doesn’t let water in when it’s raining and takes quite a strong wind to make it inside the jacket.
Personally I don’t find my waterproof warm enough for sitting around in. If you ask your friendly local outdoors shop for a “belay jacket” their eyes will light up while they think of commission. A good belay jacket is well insulated, light, packs down small, has a hood, is windproof, works even when wet. I know Karen suggested a down jacket and they do pack small and provide huge amounts of insulation, but they’re no where near as warm when they’re wet and they take weeks to dry out. There are synthetic equivalents that work well when wet but they tend to be more bulky. My jacket is not as warm as a down jacket but is ideal in every other way, I’ll have to get back to you on whether it’s warm enough throughout the winter.
The main problem with the layering concept is you spend all that money on a waterproof but when you want to stop moving you take it off in order to put a warm layer on underneath and in the process you can lose a lot of heat and get wet. Paramo have a range of products that are designed to be used so that you don’t have to take anything off in order to put something on. You just put a warm jacket over the waterproof jacket. As Paul has mentioned Paramo gear is expensive, which is why I’ve not experimented with their take on layering. It does sound like it’d be ideal for sota. Expensive gear does tend to last longer though.
Another piece of kit I take is a 4-6 person shelter, it cost about £30. It is completely windproof and you can sit up in it, it weights perhaps 1Kg and there is no way I’d want to share it with 5 other people. I bought it after doing an outdoors first aid course but have never used it in that kind of situation. I have however sat down on a snowy slope at over 4000m in altitude on a fairly chilly day and got warm enough to have a nice nap while I waited for some friends. When they got inside too in order to eat lunch out of the wind we had to take our jackets off as it was too warm. Just be careful people don’t think you need rescuing!
Right, I’ll leave it there, the post has got quite long sorry. I wanted to be thorough in case other people came to read your question in the future. I know I learnt a lot by reading the reflector before beginning activating.