UKC

I understand what it means scientifically but in the real world how do people judge what they need as a minimum, do3es a scale something like the following sound reasonable?

1500 - shower proof
3000 - downpour proof
5000 - storm proof

and how much does the HH degrade with time?

In reply to antdav:

1500 - Will hold in a wet fart
3000 - Can withhold a minor dribble (remember kids 3 shakes is a w@nk)
5000 - Drunken sleep piss just runs down the inside.

In reply to antdav: I would put storm proof as 10000, down pour as 5000 using your words, in terms of 1500 which is British standard waterproof........ I would say keeps most off to a point but generally get wetter inside if wearing for a long time as you tend to find they aint that breathable, i.e. short useage emergency lightweight jkt.

degradation is tested by 40 washes in the lab I think could be 10, usually somewhere around 10 to 25% loss depending on weights of fabric waterproof bit applied to, in real use, hard to say as most jkts fail from abraison in an area rather than degradation. If you talk expensive stuff, in theory, they dont degrade, but thats another argument..

In reply to gear boy:

I'm assuming he's probably talking about tents actually. HH's of 1500-5000 certainly fall into that category when compared to what you would expect from a jacket.

For example Gore tex pro shell has a HH of about 40,000mm, Event about 30,000mm

As far as tents go i'd say 5000 is pretty storm proof. That's what mine is rated to and its never had a leak, equally i've seen eurohike tents with 1500mm HH's wet through in a few hours.

Chances are anything over 3000mm would be fine for most uk use.

In reply to Stuzz: aye, i did mean for tents even though the trouser scale is the best response so far.

In reply to antdav: Hydrostatic head is water pressure before leaking??? If so then when does water pile up on a tent?? Mine usually runs off!

In reply to antdav: Ok I have a tent with a 5000 fly, it mists up inside in a storm.

In reply to hatchleader:

Nice thought, but a water droplet hitting your tent, being driven by wind, exerts a pressure on the fabric, and at a certain pressure will smash through it, hence "misting" inside tents in storms, leaking tents are ususly poor designs or seam failures.

In reply to gear boy:

Do you think its actually the fabric leaking or just condensation?

In reply to antdav:

And there was me thinking hydrostatic head was a very special reward from a lithe lady friend whilst in the shower . . . ;0P

5000 = absolutely sucktastic
3000 = slurptastic
1500 = blowtastic

Don't worry I've already got my waterproof mac on & by the time anyone reads this I'll be gone . . .

So HH is misting rather than dripping. So a 5000 tesco value will drip and a 1500 Vango will mist in light rain?

In reply to Stuzz:

in a storm the "misting" is rain drops smashing through the fabric not condensation, which would collect on the inside of the tent, sat there and watched it happen in an alpine storm

In reply to antdav: if we are talking tents then dripping is a leak caused by seam failure, poor design etc. so yes a 5000HH tent fly can leak and still be "waterproof fabric"
the Tesco tent or the Vango tent could both drip in rain,

Its very subjective as HH is a static pressure test in a lab and rain falls from the sky, with wind effect this causes variation, i.e.light rain driven by heavy wind could cause misting but heavier rain no wind might not