So newb on this base layer stuff. For merino wool or poly blend long sleeve in 20-40 degrees - do you wear that straight against the skin/no t shirt? I'm looking to DE-dampify my commute. I'm trying to figure out a new layering system where I don't show up to work soaked and freezing like last year.

Yep. Any wicking base layer (wool, poly, etc) should go directly against your skin. Avoid cotton in general if the goal is moisture management. Cotton is great at absorbing moisture, but holds onto it instead of moving it along.

wool is the "wicking layer" directly against the skin. Typically used in a multi-layer scenario topped by breathable wind shell (if wind protection is needed)

A wool baselayer does not keep you from soaking it just keeps you from feeling like it. Sort of. I have one each of wool and hi-tech wicking baselayer. Actually I have two in wool, one long sleeved and thicker material and one short sleeved thinner, both Merino. The hi-tech baselayer is thin but warm anything is better than cotton. My cycling jackets are breathable soft-shell so they play nice with baselayers and are water resistant. The baselayer and jacket are good down to freezing. Add a fleece layer and I've gone down to the mid-20's.

FYI, I use $5 merino sweaters wool from Salvation Army. I have $100+ merino, but I don't worry about salvation army stuff.

I quit using synthetic so much as it really stunk. After a while even washing doesn't fully get the stink out. Merino, I can sweat in a week or two and it still isn't as bad as one day in synthetic.

Food for thought.

Yes, wool or synthetic is the wicking layer.

IN order not to sweat, you have to ballance breathabilty/warmth against sweat.

I start out my rides slow, typically just protect my chest from wind (vest), and like to use arm warmers that I can pull down if I get too hot. Obviously unzipping the layers can help moderate the body from sweating.

Just don't wear cotton.

Merino comes in different weights. Even in very cold weather I will typically wear only two layers of merino--both long sleeve, the lighter 150 wt crew neck and the heavier 200 wt turtleneck--under a windproof she'll. I don't find anything more comfortable than merino. Another advantage is that I can wear it daily for weeks without washing since it doesn't hold odor. Synthetics stink if you look at them sideways for 5 minutes.

And, merino has a very broad temperature range. I'll go from 50 degrees to 90 degrees with the same weight shirt.

All natural fibres come in different grades or diameters. Fine grades are suitable for use next to the skin. Coarser grades are itchy, so better suited to midlayer use.
Fine grades of merino (superfine grade) is a very expensive product, so is often diluted with coarse grades or with synthetic fibres.
With any baselayer, use a suitably breathable shell and insulating midlayers to control heat loss. If you are sweating heavily every day, wear less insulation, and less windproofing. Save waterproofs for actual rain.
On a winter commute there should be no need to sweat.

Any tips on mining a Salvation Army for merino? Do you just have to know what it looks/feels like to pick it out, or do you go checking every tag in hundreds of sweaters?

OP....you haven't shown your location. Makes recommendations a bit tough. Not all things work everywhere. Especially when cold temps and..............relative humidity are combined.

If it is cold combined with high humidity there is little you can do but rely on clothing vents to provide airflow to remove moisture. You can't cheat Mother Nature, so the best "breathable" material that can be thought of to produce will not pass moisture through in very humid conditions. You will sweat without airflow.

That being said my vote is cast in favor of Merino Wool. It's the only thing that I'm looking for as the cold, cool to Northerners, months approach. It doesn't have to be great, "good" level is adequate for biking

I use a midweight smartwool top against the skin:
SmartWool Midweight Crew Top - Wool - Men's - REI.com

And the Showers Pass Elite jacket as the outer shell:
https://www.showerspass.com/products...lite-21-jacket

That works between about 40f-20f. Colder than that and I wear an additional layer of a smartwool sweater.

I've been thinking about trying out Windstopper for the outer jacket instead of a rain jacket like the showers pass above is.

I sweat on every ride, cold or not. Try 18 miles of headwind.

Do you wear a windproof or waterproof?

I sweat, and when it is colder I sweat more because I go faster to keep warm. Any synthetic close to my skin starts to smell horrible on me before I leave the house. Nothing that is rainproof breathes enough. I deal with wind by using lofty fleece to help cushion the blow, or I just go faster.

I'd love to have access to the Salvation Army places you guys seem to find. I've been down there a few times and I've never seen any wool at all. The place is full of clothes, all of it horrible.

I've seen some long sleeve baselayer stuff on Amazon for $60 or so. What would you recommend to someone who's never owned wool before?

I need to do some experimentation because in about a year my company will be moving to 26 miles away and no showers.

I just look at the sweaters with half zips. Yeah, I have to look at the tag of each one, which does take some time (to save $100 per item). About 75% of sweaters are cotton, and those are easy to rule out by look and feel. So I look at the tags of the remaining 25%. Cashier is great too.

I've gotten some of them turned into short sleeves for the summer, some left as long sleeve for the winter. Smartwool merino arm warmers are not too expensive and work great too...

Oh, England. Not much snow or studded tires? They both add to the sweat factor for winter riding. One of my studded tires weighs like 950 grams, and is like riding though wet tar, not much coasting. Snow, 'nuff said. Back to my jacket, Windproof front on a lightweight running jacket, plus wool base layer and thicker wool sweater, varies by temps. Some of just sweat more. Even at 20 F.

polarguard fleece has a surface treatment to pull moisture to the garment surface . the fiber itself is not absorbant .

A Lot of the sweat can then be removed by taking it off and flinging it against a railing .. then putting it back on .

It depends on your metro area as well. Upscale suburban stores may have nicer stock than urban stores. In larger cities, donations to non-store locations are taken to a central location, and parcelled out to the local retail shops. Donations to a store may or may not be processed and stay at that store. For Goodwill in particular, nicer suburbs have nicer clothing.

That's exactly the combination I was eyeing for this winter in Chicago. The Showers Pass 2.1 is expensive but last winter I went cheap on everything so this time I'm going to splurge a bit.

Q-> Is that jacket overkill for use primarily as a shell?

Yep I'm hearin that on Chicago lakefront last week.

Thanks for the knowledge!

On a lower note - > My guys get cold as hell in Fall/Winter - I think mainly because I can't stay dry down there - I'm going to try some wool this year and see if that'll work better.

Thx for the tips, I'll pop over on my off Friday and take a look in the SA literally next door to where I live. I'm pretty optimistic, as it's a pretty well-off suburb and I've found some pretty nice stuff there before, including my very favorite shoes, which are a pair of Keen Jaspers that hug my feet so lovingly I call them my "kittens" -- cost me I think $3.50.

I don't find that cotton is bad against my skin, though lots of cyclists say that. Sometimes I'll wear a thin merino wool shirt over a cotton shirt. But I like merino against my skin, too.