A "good" waterproof jacket typically has a waterproof rating of 5,000mm or higher, though the ideal rating largely depends on the specific weather conditions you expect to encounter and the intensity of your activity. There isn't a single "exact" number for all scenarios, as what's considered good for light rain differs significantly from what's needed for heavy downpours or extreme outdoor activities.
Understanding Waterproof Ratings (MM)
Waterproof ratings, often expressed in millimeters (mm), measure a fabric's resistance to water pressure. This rating, known as a hydrostatic head, indicates the height of a column of water (in millimeters) the fabric can withstand before water begins to seep through. A higher millimeter rating signifies greater waterproofness.
Here's a breakdown of what different waterproof ratings mean for your protection:
| Waterproof Rating | Resistance Level | Recommended Weather Conditions |
|---|---|---|
| Up to 2,000mm | Water resistant | Very light rain |
| 2,000mm–5,000mm | Waterproof | Light to average rain |
| 5,000mm–10,000mm | Very Waterproof | Moderate to heavy rain |
| 10,000mm and above | Highly Waterproof | Heavy rain |
Choosing the Right Waterproof Jacket for Your Needs
To determine what "good" means for your jacket, consider your typical activities and the weather you're likely to face. Matching the jacket's rating to your needs ensures you stay dry and comfortable without overspending on unnecessary protection or being underprepared.
For Casual Use and Light Showers
If you need a jacket for daily commutes, short walks, or unexpected light rain, a lower waterproof rating might suffice.
- Recommended Rating: 2,000mm–5,000mm
- Practical Insights:
- Suitable for urban environments or brief exposure to light drizzle.
- Often more breathable and lighter, making them comfortable for everyday wear.
- Look for features like a good hood and sealed seams to enhance protection.
For Moderate to Heavy Rain and Active Outdoor Pursuits
For activities like hiking, cycling, or working outdoors where you'll face average to moderate rain for extended periods, you'll need a more robust waterproof rating.
- Recommended Rating: 5,000mm–10,000mm
- Practical Insights:
- Provides reliable protection against persistent rain without feeling overly bulky.
- Many jackets in this range offer a good balance of waterproofness and breathability, essential for active use.
- Consider jackets with adjustable cuffs, hems, and hoods for better weather sealing.
For Extreme Weather and Demanding Environments
If you plan on mountaineering, trekking in consistently heavy rain, or spending long periods exposed to severe weather conditions, a highly waterproof jacket is crucial.
- Recommended Rating: 10,000mm and above
- Practical Insights:
- Offers superior protection against torrential downpours and driving wind-driven rain.
- These jackets are designed for maximum durability and weather resistance, often featuring advanced membrane technologies.
- Essential for safety and comfort in challenging outdoor adventures where staying dry is paramount.
Beyond the MM Rating: Other Factors to Consider
While the millimeter rating is a primary indicator of waterproofness, other features also contribute to a jacket's overall effectiveness:
- Breathability: Measured in g/m²/24hrs, breathability is crucial for preventing sweat buildup inside the jacket, especially during physical activity.
- Seam Sealing: Even a highly waterproof fabric will leak if its seams aren't fully taped or welded. Look for "fully seam-sealed" jackets.
- Durable Water Repellent (DWR) Finish: This coating on the jacket's exterior helps water bead up and roll off, preventing the face fabric from becoming saturated.
- Zippers and Pockets: Water-resistant zippers and storm flaps over pockets are vital for keeping your essentials dry.
Ultimately, a "good" waterproof jacket is one that reliably keeps you dry and comfortable in the specific conditions you intend to use it for. Understanding the waterproof ratings and other design features will help you make an informed decision for your outdoor gear.
