Why not using breathable fabric? 
The new Tribord CR100+ jacket was designed with Novadry technology. It provides optimal waterproofing and breathability,while being lightweight (690g) and affordable (£20.95)!

Tribord CR100+ jacket

The third Decathlon technical brands website is on line. After Novadry and Equarea, here comes STRATERMIC. Stratermic is the brand of thermic insulation, that brings warmth, lightness and durability to Decathlon Passion Brands sport clothes.
Stratermic adapts itself to the level of cold, from -50°c to +18°c, and to the intensity of your sport activity.

Read the article about Novadry technology in Quechua Magazine 15.