Updated: Jan 18, 2021
First things first, as a rule are down jackets waterproof? No, unless there is an extra waterproof membrane fabric on the outside of the down it won’t be waterproof. Tip: If you can see stitching its not waterproof, and when down gets wet it won’t be able to keep you warm anymore.
Synthetic insulation will still keep you warm when wet and is easier to wash and take care of. So if you are planning to wear an insulated jacket without a waterproof often in a rainy climate I recommend a synthetic jacket.
What is warmer down or synthetic?
Down has the capabilities of being warmer than a synthetic counter part, but it really depends of how much insulation is in each jacket and the quality.
1. Quality; Look at the fill power of the down, most of the mid-range down jackets will be 700 fill power. More technical/expensive down will be 850+ fill power which means the down lofts up more trapping more warm air.
2. Quantity; Look at how many grams are within the jacket. The more insulation gram for gram will be warmer. A lightweight packable jacket will contain roughly 90-120g of insulation, an all round warmth jacket will contain around 120-180g, and then you’ll start getting into the really warm jackets from 180g+.
Note – a 850+ fill power jacket with 120g will be warmer than 650+fill power jacket that has 160g.
Do down jackets feel different to synthetic jackets?
Their warmth feels slightly different if you focus on it, synthetic warmth feels a bit punchier, and down feels like you are in a warm room.
Which is more packable?
Down without a doubt is more packable, so it is the perfect choice for transporting in backpacks with minimum weight and room in your pack. The more warm, packable and light the more expensive it is.
Note - Don't store your down in a small bag, as it can ruin your jacket. Store it in a large bag or hung up.