How to stay warm outdoors
Almost everyone who gets cold outdoors does not get cold because they dressed too thinly. They get cold because they dressed too warmly, sweated while moving, and then stopped. A wet layer against the skin pulls heat away several times faster than a dry one, and from that moment no jacket will save you.
So layering is not about how much you put on. It is about how quickly you can take something off and put it back on when the pace changes. This guide goes through the three layers, the grams you see in product descriptions, and four real scenarios.
Three layers and what each one does
Base layer: moisture management
The bottom layer does not warm you. Its job is to move sweat away from the skin. That is why cotton is a mistake here: it absorbs moisture and holds it against your body. You want synthetics or merino.
In the catalogue that is the M-Tac Delta Level 2 line — a 100% polyester top at 250 g/m² and matching thermal bottoms. For active movement the lighter M-Tac Sweat-Wicking T-Shirt Gen.II works better, and for deep cold there are M-Tac winter 3/4 base layer bottoms with Pontetorto® fleece. The full range is under thermal base layers.
Mid layer: warmth
This is where heat is held. Fleece is the standard because it insulates even when damp and dries quickly. The difference between models comes down to grams per square metre.
At the light end, a 180 g/m² polyester fleece or a Polartec® hooded fleece at 140 GSM: these suit movement because they do not overheat. In the middle, a STORMFLEECE jacket at 256 g/m². At the heavy end, the Helikon-Tex Alpha Tactical at 310 g/m², which is made for standing in the cold rather than running in it. There are hybrids too, such as the Helikon-Tex Patriot Mk2 or an M-Tac ECWCS Gen.II level 3 fleece. Look under fleeces and sweatshirts.
Outer layer: wind and water
The outer layer does not warm you — it protects the warmth from wind and moisture. The decision here is between softshell and a membrane.
Softshell breathes better and suits movement in dry weather: a Trooper Mk2 in StormStretch® fabric, or an Artaxes softshell with Teflon® DWR rated at 8000 mm. A membrane jacket is what you need in real rain: a GEN V 3.0 parka with a Storm|Tex membrane or a Hoplite nylon rain jacket at 5000 mm. Insulated options such as the Wolfhound Lite or the Wolfhound Hoodie Lite with 40 g/m² fill and Windpack suit static work in the cold. See jackets and waterproof clothing.
What the water column and DWR actually mean
The number in millimetres — 5000 mm, 8000 mm — is the water pressure the fabric holds without letting water through. 5000 mm is enough for normal rain; from 8000 mm you are covered for longer downpours and for the pressure under backpack straps, where the pack presses the fabric against you.
DWR is a surface treatment that makes water bead and roll off. It wears out and needs renewing — that is normal, not a defect. When a jacket starts "drinking" water on the surface, the membrane is still working, but the outer fabric is saturated and has stopped breathing.
Scenarios
Static duty in the cold
Little movement, almost no sweat — you can afford to go thicker. A 250 g/m² base layer, a heavy fleece around 310 g/m² and an insulated jacket. What works here is insulation, not breathability.
Training with movement
The hardest case: alternately hot and cold. Take a light base layer, a mid-weight fleece (180–256 g/m²) and a softshell you can open quickly. The rule is simple — start out slightly cold. Ten minutes of movement will make it right.
A wet autumn
Around freezing, and everything is damp. Synthetic base layer, fleece, and a membrane rated at least 5000 mm. Softshell will not help here — it wets out.
Hiking with a pack
The pack presses against your back, so your back sweats most, and the straps abrade the DWR. Take a lighter mid layer than you think you need, and avoid a thick jacket under the straps — better to stop and put it on at a break.
Extremities: where heat goes first
Your torso can be dressed perfectly, but if your fingers and ears are freezing, none of it matters. Three places worth covering separately:
- Feet. The sock matters more than the boot. A wet cotton sock in the cold is the shortest path to a cold injury. See socks.
- Hands. Thick gloves you cannot work in get taken off — and then they warm nothing. Choose gloves you will actually keep on: gloves.
- Head and neck. A thin cap under a helmet, or a balaclava, covers what a jacket cannot reach — forehead, cheeks, neck: headwear and balaclavas.
Common mistakes
- Cotton against the skin. It soaks up sweat, holds it there and takes hours to dry.
- One thick layer instead of three. You cannot regulate it — only put it on or take it off.
- Setting out warm. Ten minutes later you are wet, and at the first halt you are cold.
- A membrane for everything. In dry weather it traps moisture inside; softshell is the better answer.
- Forgetting the extremities. Three correct layers and cold hands still means you are cold.
Frequently asked questions
How many grams of fleece should I choose?
140–180 g/m² for movement, around 250 g/m² for general use, 300 g/m² and above for standing still in the cold. A heavier fleece is not better — it is simply made for a lower pace.
Softshell or membrane?
Softshell for movement and wind, because it breathes better. A membrane for rain. If you are buying one jacket for everything, a membrane is the safer choice, but you will sweat in it sooner when moving.
Is merino worth the premium over synthetics?
Merino smells less after several days and insulates when damp, but it dries more slowly and wears out faster. For a single day you will barely notice the difference; over several days without washing, you will.
Can I wear fleece directly against the skin?
You can, but fleece does not manage moisture the way a base layer does. Sweat will sit between your skin and the fleece, and it will chill you when you stop. A thin base layer costs little and changes the whole system.
Where to start
Start with the base layer — it is the cheapest and makes the biggest difference. Then add fleece according to your pace, and choose the outer layer by the weather rather than by the season. Browse thermal base layers, fleeces and jackets, and if you are unsure about the grams, write to us and tell us where and how much you will be moving.