Western Mountaineering: mf or dryloft

The MF is lighter, drapes and packs better, and is more breathable.

Dryloft is more water-resistant.

Unless you are in an extremely wet, unprotected environment, I personally would choose the MF.

That was what I was thinking. When you say wet and unprotected you don't think that it is waterproof. You couldn't, say, not bring a bivy if using under tarp? Or what.Would the dry loft fight the wetness you get by brushing up against a wet tent. What about wind resistance. Does the dry loft make the bag alittle warmer?
Josh

Joshua,
The dryloft will add warmth to the bag due to the wind resistance of the material. It will also help with moisture penetration but the stitching will still allow for moisture to get into the bag if allowed to accumulate, or puddle, on the surface. IMHO the dryloft adds protection and durability but it comes with the penalty of the added cost and weight when compared to the same bag in none dryloft/mf. If your main shelter is a tarp / bivy combo you can save the money and go with none dryloft. If you use a tarptent or such and do not carry a bivy the dryloft can be well worth the added expense for protection from interior condensation, again this is just my humble opinion.

Thank you for your comments.
Josh

In a bivy, you definitely don't need dryloft as you have the outer layer of the bivy to give spray and wind protection.

Under a tarp without a bivy in poor weather you are mad without a bivy so we won't consider that scenario!

In a tarp tent dryloft may help with wind protection. But is the additional weight of dryloft equal to the equivalent weight of down? Look here http://www.nunatakusa.com/site07/arc_products/arc_alpinist.htm and you will see that Epic vs Quantum equates to 3oz. 3 oz of down is a 25% increase in total down. Hard to call on this one, the wind may chill you more in Quantum but the higher density of down will keep you warmer.

In a tent (see Rogers article on an extreme experience without dryloft in winter) I dont feel you need dryloft. You have both wind and spray protection already.

I can see where this is going. So is the dry loft for Everest and such?

Josh

> So is the dry loft for Everest and such?
Can be useful in snow caves and igloos when the inside surface of the snow is wet/dripping.

Cheers

Roger has it right. :)

For damp conditions near freezing, especially for short trips, highly water-resistant shells (e.g. eVent, Dryloft, etc.) have their place. Still, I would rather put my moisture barrier someplace other than the shell of my bag if possible (like a nice tent or bivy). I say "short trips" because you'll likely accumulate moisture each night and gradually lose loft and warmth as it is difficult to dry anything in these conditions.

For sub-freezing conditions the ability to dissipate internally generated moisture trumps resistance to external moisture and I would prefer the MF shell.

For longer trips in just about any temperature range/conditions, a WP/B shell on a down bag usually causes more problems than it solves. It will dissipate less moisture and take longer to dry should a weather break permit gear drying. (As Thom said, even if the bag shell is wp/b like Gortex or eVent, the seams are not taped, so no bag should be considered waterproof and suitable for use without some kind of external moisture protection.)

Cheers,

-Mike

FWIW I never had issues with moisture build up in a Dry Loft shelled -20 down bag, even when used for 10+ days in a row. It was rather cold, however.

The MF Western M. uses is just awesome. Great blend of attributes.

Thanks you guys for the info. Roger what happened to your Avatar? I loved your shirtless skiing one. Until my next question.

Josh

Hi Joshua

> Roger what happened to your Avatar?
Oh, 'that' avatar picture is still on file. It may return one day. :-)
The current avatar picture was taken on our most recent ski tour. That was our lunch spot one day. A FAR cry from the previous trip!
.

The summit of Mt Jagungal. We skied back down.
We got a wee bit of condensation on the foot region of our top quilt that night, but not much. It dried off during breakfast, before we packed.

Cheers

A wonderful photo and a wonderful mountain, thanks for the reminder. And there are some great campsites below if I recall correctly.