I had 4 days of testing this weekend in pretty cold conditions in the adirondacks and have narrowed it down to what I think will probably be the perfect baselayer for my needs.

This baselayer is going below a vapor shirt from RBH.

it needs to be:

-as lightweight as possible, in other words not thick/warm but also gram light too!
-a design that encourages small pockets of air to be trapped/warmed
-have a snug fitting hood
-hydrophobic
-ideally a chest pocket to warm my snacks but this is not a deal breaker

I tried a patagonia R1 hoody, a sugoi shirt that is windproof on the front and has a roubaix fabric on the rear (it's from my cycling collection), an old EMS bergelene midweight baselayer, and finally a climatize EMS powerdry/merino blend.

my favorite was the r1 but it's heavy and gets even heavier when soaked with sweat. a lighterweight version of it would be ideal but i don't see one on their site.

How about a Patagonia Cap4 hoody or MEC T2 hoody?

Patagonia Cap 4 hoody? It seems like just what you are looking for a lighter version of the r1.

if you want something to wear under a vbl layer:

try a fishnet garment, like brynje. there is a ton of information about such layers on bpl, just search for them.

if you don't fancy this try something like the helly hansen lifa baselayers.

they don't have hoods, though. just use a balaclava.

Edited by sol on 02/19/2013 12:45:03 MST.

Check out the Ibex Indie Hoodie. Not as heavy as the R1.

I thought there was the cap 4 hoody, but am unable to find it on their site.

I'd love the fishnet stuff but am unable to get it as far as I can tell in the states and it is also extremely expensive last time I checked when sent from Europe.

I don't want a balaclava as I have a hat and face mask combo I like a lot more when I need the protection.

I've lost faith in wool recently and dont want to consider it. It absorbs too much water beneath the vapor barrier and does not dry that fast compared to synthetics.

the MEC is looking good. Thanks for that suggestion.

At MEC the T2 is slightly lighter weight than the Cap 4, The new T3 is very close to equivalent to the Cap 4(the old T3 was an R1 equivelent) and the MEC Vega is the R1 equivalent.

The T2 green model is on clearance right now for $25. A fantastic value even if it doesnt meet your needs perfectly. For me this a perfect down to 20F running base layer or from 50F to 32F hiking base layer underneath a windshirt.

Sean,

My recent purchase of Cabela's ECWCS zip T neck tops has amazed me.

The Polartec Power Dry fabric has a "gridded" interior of little 1/8" square pillars that insulate amazingly well but weigh little.

I have mainly worn it for ski patrolling and some for back country skiing. Now I'm getting the bottoms because I'm so sold on the fabric design. It truly beats my other polyester long johns for warmth-per-weight. AND it seems to transport sweat better.

Cabela's has even lighter underwear that uses three different weights of polyester fabric to insulate your body only as much as needed. i.e. arms get less insulation than the torso and the torso is "mappped" with different weights of insulation.

P.S. I'm sure there must be other companies that use this PolarTec fabric as well.

Edited by Danepacker on 02/19/2013 13:23:10 MST.

I got the green T2 on sale recently. Its really a nice garment. It has a fairly slim fit with long arms. The hood is snug on my melon head but its pretty light and stretchy so there is no binding. My whole family laughs at me when I wear it though. There are jeers of "Hey Kermit" and "Welcome back Teenage Mutant Turtle". I think I like it even better now.

lighter than an r1 - look at the bontrager b3 hooded baselayer: http://bontrager.com/model/11005

everything but the pocket. good to cross-pollinate with cycle gear.

I'm not an expert on VB's but I think you need something a lot thinner than a cap 4 or T2. You shud only be a little damp, never soaking wet. Check out what andre skurka has to say about VB's on his blog.

I think any gridded fleece will be overkill under a VBL. I'm thinking 140wt merino or capilene 1 at most. What kind of temperatures are you trying to stay comfortable in?

Is your VBL for active use? or only for night time sleeping use?

Edited by Konrad1013 on 02/19/2013 15:04:11 MST.

"I thought there was the cap 4 hoody, but am unable to find it on their site."

I emailed Patagonia today asking about this piece, and they said it would be out of stock likely until July or August.

Why are you wearing ANYTHING below? The VaprThrm material's inward facing material (at least what I used several years ago) was comfortable enough to use against the skin. I do use an ultralight pair of liners with my RBH socks, but that's about preventing blisters not against the skin comfort. If you really want something between you and the RBH vapor shirt, I would go for something silk or featherweight like cap1.

--Mark

This weekend I was in temperatures ranging -30F at the extreme and most the time probably around 0F with windchill. I was doing long day hikes with lots of elevation gain at a fast pace.

I get cold VERY easy especially my hands and feet although I'm learning from this forum how to avoid this with good results, and I must also note I'm new to RBH and vapor clothing. They suggested I wear something underneath and to try various combos to see what works best thus this post for what I see as ideal...I'll try the next to skin one day this weekend and see how that goes.

I have some very lightweight long underwear that I have tried commuting to work on my bike with good results but was hesitant to test it for 12 hour hikes with unpredictable extremely cold (for me) weather. I didn't want to freeze:)

with vapor barrier clothing the idea is to keep the surface of your skin at an ideal humidity to minimize perspiration. The smaller the "humidity" zone, the better. The reason many people do a base under vapor barrier is because several of the materials used for vapor barriers (like si nylon or plastic - bread bags for the feet :) feel very clammy/uncomfortable next to skin. So an ultra thin base is worn to keep it away from the skin, but to minimize the size of the space where you are running the high humidity zone. The items I have from RBH has an inner surface which is decent against the skin, so its possible - at least for me - to do away with the base.

As to staying warm.. that's the job of insulation which is above the vapor barrier and is now protected interenally generated moisture.

--mark