Gore-TEX, a lightweight, waterproof fabric made from the expanded form of PTFE
sciencehistory.org
sciencehistory.org
None of that is correct. Water moves through Gore-Tex via evaporation, and the driver is heat. As long as it is warmer on one side of the membrane than the other, moisture will move toward the colder side. This works even if both sides of the membrane are in direct contact with liquid water.
The ePTFE of Gore-Tex is like an open-cell foam, or an extremely dense net, whose holes are small enough to exclude liquid water drops, but huge compared to water molecules. It is not one-dimensional; it has thickness. It creates essentially a thin captive atmosphere within the membrane, through which water vapor can move.
If the membrane is immersed on both sides, water will be evaporating into the captive atmosphere within the membrane from both directions. Water vapor will also be condensing out of that atmosphere in both directions. So if one side is warmer than the other, there will be a net transfer of water from the warm to the cold side. On the warmer side it will be a bit easier for water to evaporate; on the cold side, a bit easier for it to condense.
In Gore-Tex the inner side of the ePTFE is mated to hydrophilic polyurethane (PU). This is to protect the ePTFE from oils and grease from our disgusting skin. So water vapor is soaked up by the PU, and once the PU is saturated, the water starts evaporating from the PU in both directions. But again, as long as there is a heat gradient, it will result in net moisture movement from warm to cold.
There’s no doubt part of the success is the chemistry of the product, but the required independent testing to very high standards also likely plays a large part in the quality of the final products.
Edit: I checked and bought these shoes in April 2020. I guess I will try to contact them?!
The product was "Nike Air Zoom Pegasus 36 Trail GTX Gore Tex". I wonder where I should contact them?
I have used Gore-Tex only in shoes, but in various kinds of high-quality shoes (i.e. not cheap), either made by a less known Swiss company, or by brands like Adidas or Asics.
In all cases, I have used daily the shoes for 3 to 4 years until I had to dump them, always due to an excessively worn sole, not because of problems with Gore-Tex.
On the other hand, I think I went through by now about 3-4 pairs of various running/hiking lighter plastic shoes (Merrell, Reichle, Salomon) and in those the membrane is the only thing keeping the water out. Unfortunately, it's generally sewn deep into some plastic mesh, so no way to tell / maintain it even if You'd like to. And one tear in the membrane means that all the water that seeps into the surrounding mesh "will" always find the way into the failed part of the membrane. Unfortunately, the rest of the membrane then tends to still do its part in slowing the moisture on its way out. So it drains / dries much slower than shoes with no membrane.
This is the main advantage to it imho. I hike all day in Northern CA for work, so good rain gear is needed. There are plenty of options without GORE-TEX that are satisfactorily rain proof, but the ones with GORE-TEX are almost always better quality and have a better warranty. The REI Rainer is a good example of something that is generally good enough at keeping water out, but its relatively poorly made compared to their XeroDry jacket that includes GORE-TEX. It just leads to the end product being higher quality.
If your selling point is waterproofness, and waterproofness can be destroyed by bad assembly... assembly is directly linked to your perceived product value.
I had a friend come on a hike with me wearing a three layer Gore-TEX jacket on a warm, completely clear day. I think he began to overheat with it (wearing a sweatshirt underneath) while in the parking lot, before we even got on the trail. He ended up carrying it the entire way.
I used to bike commute and walk in the rain, long before even knowing Gore-TEX existed. Being warm is more important than being dry (if you're not in subzero temperatures). Wool and synthetics will keep you warm even if they're wet - I've spent a fair amount of time soaking wet but feeling fine. And stuff will dry out quickly when you're wearing it indoors.
If you're a mountaineer, sure - use Gore-TEX if being cold and wet is likely going to kill you. And don't forget all the other layers. But for normal people, we don't need it.
Then again you only say to put on a t-shirt and a jacket, no mention of pants -- I guess that's one way to solve the problem.
It never occurred to me to get a jacket made out of it.
Gore-tex shells don't breath at all unless you keep up the DWR layer on the outside such that the rain beads off. However, if you do regularly maintain the DWR layer, the garment is waterproof anyways without Gore-tex, and more breathable. Moreover, the membranes don't really last a long time, a few year old gore-tex jacket will have a broken membrane, but the nylon outside shell will still look new. I'd guess that about 95% of Gore-tex shells in actual use are no longer waterproof or breathable due to the combo of a split membrane, and worn out DWR coating.
I agree that extreme mountaineering is the one use case where it makes sense. Also, usually with a new top quality outer layer for every trip or every few trips... Even then, there is probably better tech out there, like Columbia OutDry, which puts the membrane on the outside avoiding the need for PFAS based DWR.
> If it's not raining you'll be way more comfortable with plain fabric, especially wool. If it is raining, you'll be just as comfortable in a plastic raincoat (especially polyurethane) with pit zips, and you will stay dry a lot longer in a heavy pour.
I grew up wearing both, and then later added waxed cotton. Sorry, just ick.
You can have my goretex jackets (Arcteryx, Berghaus, Mountain Equipment) when you pry them from the fingers of my not-so-cold, only-slightly-wet dead hands.
For the light constant rain in the PNW, wool with the natural lanolin intact will keep me dry all day with incredible breathability. There are a few companies that make high end wool based gear. I’m also curious if you’ve actually tried a modern higher end polyurethane shell (not PVC) that has well designed vents all over it, or are you just talking about old fashioned PVC “oilskins” which lack good vents?
I would never wear GTX for trail running, for the reason you highlight. But then for trail running, short of a torrential downpour with cool/cold temps., I doubt I would wear anything waterproof at all.
It's a fair point that with venting, PU might be much better today than the PU shells of my youth, which were totally unvented.
When you’re mountaineering, sweat is really bad news. There’s a reason people wear $600 shells instead of $10 ponchos in the mountains.
Both messages above already agreed that in these situations it make sense. Sounds to me that you are arguing while agreeing :)
Things don't dry on boats. Wool and cotton clothing works like a moisture farm until they rot or fall apart otherwise.
Best application is sleeping bag covers. Worst application is boots. Makes no sense.
If water ever goes over the top of the shoes, it is impossible for it to leave the shoe (since it is in liquid phase, not gaseous like water vapor).
Regular shoes that basically don't breathe are unusable when it's more than 20-25º C. It's not always practical to carry around two pairs of boots when out on a trip.
My pair of boots are usable in the rainy European winters at 0º C, all the way to the scorching heat of the Arizona desert. With regular shoes, I'd just freeze in the winter or have swampy feet in the summer. The wind speed sure helps in the latter, but it works against you in the former.
Waterproof boots though are counterproductive.
I would wear waterproof socks to dry my boots inside a patrol hide though.
My gortex snowboard jacket has side vents that work great when you need to cool off a bit.
However, in all those kinds of shoes, Gore-Tex has provided a very noticeable improvement, through their ability of keeping the feet dry even when having to walk through water or partially-melted snow.
Even when just walking through a city for the daily commuting, I have found this feature very valuable, especially when going to an office where I would not be able to change my shoes with a dry pair.
So I disagree that Gore-Tex is useful only in an extended outdoor setting.
Biking in general tends to put Your heart rate pretty high. It depends on intensity of course, but a brief 30-60s sprint to overtake someone or clear a traffic light will take You from a comfortable aerobic zone well into anaerobic. That means "a lot" of sweat eventually. Walking/ hiking does that a lot less.
At the same time, on a bike commute You need durability under mechanical stress (backpacks with laptops can get heavy real quick). Aaaand on top of that, ideally it needs to be reasonably cheap (or last for decades) to be economically viable.
Personally, for bikepacking, I found that the only Goretex that works is the Shakedry membrane. This is their most barebones slimmed-down membrane. Super breathable, great water / wind resistance, but it's so ligh You look at it sideways and it tears. Definitely can't wear a backpack with that one.
On the other hand, my hiking jacket is a 3 layer laminate Goretex Pro that I've used for about 8y now with 25+kg backpacks. Great, durable, waterproof, but You are right- it's not breathable enough for bike(unless You open up all the pit zips, which kinda beats the purpose of a waterproof membrane).
I regularly use a gilet and a full sweater, these work amazingly well and are worth the price.
Besides the breathability, construction is top level for sports gear.
Synthetics without a membrane will wet through, and I assure you no amount of wool sweater underneath will save you from misery when that happens (I love wool btw, literally half my wardrobe is wool sweaters).
Likewise, hiking through the wet vegetation you find in many of the forests here will soak through your pants even if it's not raining.
With snowboarding on Mt Hood, having a shell with a membrane is absolutely necessary on the days where it hovers between rain and snow. Probably the highest value outdoor equipment I've ever bought is a gore tex balaclava for weather like that. It's a huge difference.
Some of the new soft shell materials do a lot better than synthetics + DWR, but they still fail in conditions like the above.
So, similar to Chesterlon's fence, perhaps it isn't that all of us buying membrane clothing have been duped by marketing, but rather you simply don't know when it's useful.
Apparently it's just a not too uncommon family name (Al Gore comes to mind) and also used as brand name in English speaking countries. People get so upset about Toot and Coq and Gimp, but Gore seems totally OK. As a second language learner, no matter how long you learn, you will never know what's in a native speakers head.
https://gearinstitute.com/ftc-investigates-gore-tex-business...
This phenomenon is ubiquitous in English. Try saying “spring roll” or “house cat”.
For me (a native American English speaker) the context matters. When used in a name or as part of a longer name (e.g. Gore-TEX), it's totally okay. Actual gore can be upsetting, but the word itself is commonly used in content warnings and guides.
"Gimp" is different than "Coq" or "Cox" (a popular cable provider in the U.S.) in that it's considered offensive to the disabled (if the person saying it is not disabled), where homonyms for naughty bits are generally not taken super-seriously.
TIL! I always thought it was offensive because of its use in bdsm.
Unfortunately, like Teflon cooking pans, its amazing properties come from a coating with perfluorinated octyl sulfonate, a known endocrine disruptor:
I also doubt you would get similar endocrine disruption with PTFE polymerization biproducts since you won't have the "polar head/fluorinated tail" structure that PFOTS has.
does that count as being overused, or just as intended?
Either way, my concerns are mostly: how much fluorinated waste they release from factories and what happens at the end of product lifetime. Solid fluorinated compounds don't seem atrocious, as they can be reduced to safe minerals if burned properly unlike the spray-on compounds and factory leakage.
One is called GenX and Chemours (DuPont) has been poisoning the city of Wilmington.
The video covers Chemours, DuPont, etc. and how there's a town in the US where the rain and soil is poisonous due to PFOA production in the past (and still on-going: not PFAS but other deemed-safe-by-corporate-lawyers PFOAs). The man who they interviewed had pet dogs that he would let outside and the husky loved being outside in the rain. However, the dog developed sores / lesions on its back and then died. Turns out the groundwater and basically the whole environment around the PFOA factory is highly toxic.
The video also interviewed a worker at a PFOA plant in Germany who has (had?) thyroid cancer, I believe it was, and suffers from many disrupted endocrine system effects. (He worked inside a PFOA factory where sometimes the chemical vapor would condense on the ceiling and drip down on to the workers. Again, the ground water and soil there is not safe for human or animal consumption.)
They also cover / touch upon the lawsuits that farmers with grazing cattle (that died off) tried to bring against PFOA manufacturers like DuPont, Chemours, etc. Unfortunately, most of those farmers are now dead due to cancers of various sorts (from consuming PFOA-laden groundwater, the same water which they were giving to their animals which died by the hundreds a few decades ago).
They also touch upon how difficult it is to recycle PFOA-containing fabrics: they must be incinerated at much higher temperatures to render the compounds inert and safe for disposal in the way that regular trash is disposed of after incineration.
PFOS was used in the manufacturing process. It’s quite problematic, but it’s actually the end product.
Tungsten: one of the early breakthroughs was when General Electric figured out how to make ductile tungsten wire and coil it. Tungsten powder is compressed into slugs, which are forced through successively smaller dies. At some point, ductility appears. The rods can then be pulled through still smaller dies until very fine wire appears. This is how incandescent light bulbs were made. (Revisionist history of the light bulb: In 1840, Warren de la Rue invented the light bulb. Basic concept: use a coil of thin wire with a very high melting point. He used platinum. Worked fine, cost too much. Then there was a detour through carbonized paper led by Edison. Not as good, but cheaper. Then, in 1905, William Coolidge figured out how to make tungsten ductile. Now de la Rue's approach was affordable. Carbonized paper was abandoned.)
Steel: It's been known since ancient times that you could heat up a piece of iron and punch a hole through it, widening the piece at that point. That concept can be taken to an extreme. Within a narrow temperature range, you can push a piercer through a long steel bar endwise and turn it into a pipe.[1] That's how thick-walled pipe is made.
Food: The Beyond Meat process is more mechanical than chemical. The basic feedstock is peas. The trick that gives it a meaty texture involves extrusion with both steam and cold. The exact process is proprietary but not that complicated.
This is an area where development has historically required either a huge amount of tries or a lucky accident. Which makes one wonder what new tricks can be found that way by hooking up machine learning to hydrodynamic simulation.
If I know my feet are going to be wet for 6+ hours I go with my shoes-with-drain and waterproof socks, over N layers of thin wool socks depending on temperature. I have only replaced the socks twice because I don't use em too much.
I've found for offshore sailing or backpacking in the wet that Sealskinz (not gore-tex) are the best. Still wearing gore-tex bibs and top anytime there's any wet.
It's quite interesting how these extreme expeditions work. They have to spend much of the time in the tent brushing ice off clothes, shoes, the tent itself, equipment and so on, because if the ice melts it will freeze again and shit will get ruined.
Think plastic is a problem? PTFE is way worse.
Those are the microplastic we are going to find in breastmilk forever.
https://www.goremedical.com/products/cardioform/septal-occlu...
Teflon and other PTFE based none stick surfaces are now really quite controversial due to the toxic gasses they can give off of you heat them too high. And the manufacturing processes is potentially linked to a higher risk of cancer for workers.
The industry is now moving away from PTFE to other materials for none stick surfaces, however although they proclaim these are "safe", they have been studied far less. I believe some evidence is indicative of them also having serious issues.
This is just one search result, there are many This is just one search result, there are many: https://www.foxnews.com/health/non-stick-pans-could-release-...
Personally I didn't even click on it just because of that, which is a shame because you made me interested up until then.
Anything bigger than a "small molecule" doesn't make it through the membranes into your bloodstream. Even individual proteins are too big, let alone a chunk of your frying pan big enough to see.
Either way, what you claim is simply not true by any reasoning [1], though I do agree eating teflon flakes in moderate amounts should not pose much concern.
[1] https://phys.org/news/2020-08-micro-nanoplastics-human-tissu...
Saying "Its physical properties are incompatible with human biology." is not an actual answer. What physical properties?
Fibers so small they tangle up with your chromosomes are the physical properties that can cause cancer
Look at peer reviewed papers.
Peer reviewed papers aren't absolute truth either and one usually needs to be an expert in the field to see which papers are sound and which are not, if even possible. I'd even wager there's a lower percentage of bullshit to be found on Wikipedia than in peer reviewed papers.
Crocidolite does contain iron (Na2FeIII2FeII3Si8O22(OH)2 per [1]) but it’s not the common type of asbestos and is known as blue asbestos and is found primarily in South Africa, Australia, and Bolivia.
I think given how dangerous asbestos is, it can’t statistically be reasonable to assume that it’s cancerous properties arise from something only found in a minority of the asbestos we use.
[0]: https://www.britannica.com/science/asbestos-mineral
[1]: https://fr.wikipedia.org/wiki/Crocidolite
The second link is in French.
· Don't use high heat, ever; you will destroy the coating and release toxic gas
· Don't leave the pan to get too hot over medium/low heat either; if a teflon pan ever smokes, you have officially fucked up.
· Don't use hard/sharp utensils against the pan; you will scrape off the coating
· Don't clean the pan with abrasive scrubbers; you will scrape off the coating
· Do use soft plastic, silicone, or wood utensils; these shouldn't damage the coating
· Do wipe the pan after use, while the remnants of cooking are still hot ( honestly this is just a general tip; I always wipe out my carbon steel pan after use as well )
· Do use a soft cloth or sponge and warm / hot water to clean the pan when hand washing; just like seasoned pans, you shouldn't need to clean them with actual soap all that often, but a light once over every so often will not hurt at all and helps mitigate dust/general grime.
· Do soak the pan if you have somehow managed to carbonize food onto the pan; attempting to pry off stuck burned food can pull off parts of the coating.
Personally though I'd recommend a stainless or carbon steel ( cast iron if you don't mind the weight ) and seasoning it, or basically anything with a ceramic coating ( all cliff notes apply to ceramic as well, but due to general coating damage concerns rather than ptfe's production of toxic gas and generation of microplastic granules )
PFAS is a family of Per or poly fluoroalkyl substances.
Basically it's a group of substances that have very long ass Carbon and Flour chains.
https://www.epa.gov/pfas/pfas-explained
PTFE is a polymeric plastic. They don't fit this definition by the EPA "PFAS are found in the blood of people and animals all over the world and are present at low levels in a variety of food products and in the environment."
You could argue that the precursors to PTFE are included (but not really, since PTFE is made from a gas).
I've been moving away from PTFE in favour of cast iron cookware. Besides many other great properties, it is non-stick if used correctly.
https://old.reddit.com/r/castiron/comments/z4vdyd/some_slide...
Bob Gore is known for being a savvy businessman, and this is one example of how to turn a 20 year patent into a 100 year revenue stream.
I've tried probably a majority of the major alternatives. Every winter sports company will claim their version of goretex is just as good, but they all fall short, usually waterproofing, or sometimes they just suffer from the garbage bag effect.
Either way, I've spent hundreds of dollars on too many copycats to ever bother with non-goretex again. It's not financially worth it
That being said, for fishing where you are going to get fish guts everywhere, lots of people are now wearing this super cheap Frogg Toggs brand rather than rubbers. There is a place for super cheap PTFE gear.
Cheaper waterproof (not breathable) layers with ventilation (pit zips on jackets and full length zippers on pants) is the way to go. Paying premium for GORE-TEX has not been worth it in my experience.
Yes, GT is not 100% waterproof. It's also not breathable like cotton or untreated polyester.
However, the right path IMO is to compare GT to the alternatives, and when you do this it is absolutely clear to me that it's better. More waterproof than very breathable fabrics, more breathable than very waterproof fabrics. The former get you (very) wet from the outside, the latter get you (very) wet from the inside; GT gets you a bit wet from both.
Nobody has made the "perfect" fabric for wet conditions because it likely cannot exist. The fact that GT is not this mythical "perfect" fabric does not, for me, detract very much from it being measurably and experientially superior to the alternatives.
Unfortunately if you read his other writing about Gore-Tex (and waterproof breathable membranes in general), it is clear he does not understand how the technology actually works. He refers constantly to ambient humidity, which is irrelevant, and even gets some facts about humidity wrong.
[1] https://www.fjallraven.com/us/en-us/about/our-materials/g100...
We usually considered it to be worth it.
We use Gore-TEX jackets in the Marines, and in the field you can tell who washed their gear correctly and who didn't.
https://en.m.wikipedia.org/wiki/Durable_water_repellent
Also note each jacket has a different thickness of the gore-tex layer which conditions how many hours of rain it can withstand.
You can also get "Shakedry" Gore-tex products, which don't have an outer layer needing DWR treatments at all.
So yes, you need to treat most goretex jackets with a DWR periodically.
You wouldn’t happen to have the official Marines Goretex washing manual handy, would you?
Wash in Nikwax Tech Wash, hang dry.
They have the combined budget of the next 10 militaries.
Price is NOT a high priority for their procurement team, unlike most shoppers.
Some Salomon ones might have their own custom ~equivalent tech though, probably easier and cheaper to make new products as they control the whole process, no need for licensing & testing by the Gore-Tex company.
Why PFAS are so concerning:
1. PFAS and PFOA are known as forever chemicals because they virtually never break down under normal conditions and therefore bio-accumulate in all living organisms.
2. 99% of Americans are known to have toxic levels of PFAS or PFOS in their blood. Toxic levels of PFAS are found in rainwater all over the world - even Antarctica and Tibet. There is no rainwater anywhere in the world that is safe to drink.
3. There is no known safe level of PFAS/PFOS in the system. The EPA currently rates the recommended level at under 0.04 parts per trillion. The best testing methods can only measure as low as 4 parts per trillion.
4. PFAS are known to cause an incredible number of diseases including various cancers, obesity, liver disease, thyroid disease, kidney disfunction, and a wide range of fertility issues in both the parents and the children.
[0] https://www.gore-tex.com/pressroom/press-release/responsibil...
[1] https://toxicfreefuture.org/press-room/gore-tex-manufacturer...
Shoes: good for a few outings (really nice on snow) but then lose their water repellency. If you have sweaty feet, your socks will get wet from sweat anyways. Just bring extra socks or wring them out periodically. Wool socks will feel warm even when wet.
Jackets: great in a downpour but if you're wearing pants, all the water just rolls off your jacket and soaks your pants. Use a weather forecast and just don't go or choose another location if it's going to be pouring out and instead settle for a much lighter water repellent layer for 100s of $$$'s cheaper that works in a light rain or snow. I use the OR Helium. Packs real small.
Otherwise, if your job requires you to stand in the rain all day, definitely invest the $$$.
Is this something worthwhile for everyday wear, or this is mainly for outdoor sports enthusiasts?
It fit me really well, for a 30-year anniversary I decided to get a new one last week. They still make the same design.
The new one uses their nano-spun FutureLight fabric, rather than a three-layer nylon(?)/GoreTex sandwich.
It's much more soft, like a woven fabric rather than plastic hard shell, and it seems to be much less weight. I really like it.
I got to try out Marmot's take on next-gen shell technology a couple of years ago. Half the weight of my 20th century jacket, very effective. The particular jacket I tried didn't fit me as well as the Mountain Light, but I suspect that most people would prefer Marmot's version: more simple, lightweight, everyday tech.
Some things were great 30 years ago; the fleece Denali is essentially the same. The outer layer is much improved.
(And I noticed that the zippers are way better, overall. I bet there's been decades of improvement in plastics (sorry, "polycarbonate") engineering.)
Steve Jobs had a beautiful phase 20+ years ago, selling MacBooks made of "the finest German polycarbonate"...
... which at the time, sounded exactly like another great sales pitch from a more elegant age...
Every time i've come across a new and improved breathable waterproofing technology recently, it comes with the significant downside that the fabric is a lot less durable. When it's raining, i wear my anorak. But when it's not raining, it's rolled up in a plastic bag and bungeed to my bike bag, or shoved into my satchel, or stuffed into a corner of my carry-on luggage. It probably does >10 hours carried for every hour worn! If a fabric can't stand up to that, sadly it doesn't matter how well it performs when i'm wearing it.
I never got around to patching that... but yes there's tough stuff.
The Marmot gear I tried, the "Durable Water Repellent" (DWR) is claimed to be more durable than previous Gore Tex products. That's important because when the surface DWR is dirty with oils or abraded, it will wet out, saturate, and while the PTFE membrane won't leak liquid water, now it's not passing vapor either: you generally end up damp or worse. Condensation etc.
Which is why Gore Tex certification covered the whole process, the final product design.
I don't yet have decades of experience with current products. But honestly comparing them, the newer ones seem to be far superior build quality. That's hard for me to quantify.
The product reviews for the North Face FutureLight gear have noted how they hold up, scrambling over rocks and during Alpine style ascent.
I think it's definitely worth it for every day wear if you're in a rainy and or snowy place. I use it in the winter, and it allows me to be warm and not wet. Normally the snow would melt or there would be rain and soak my gear after a while in the snow, or I would get soaked from my own sweat, and it would be pretty miserable. I can even bike in the rain without getting wet. Gore Tex mostly works too but these materials are much more breathable and soft, so it makes it way more practical for everyday wear.
But I'm not sure how much that really matters... a regular un-fluoridated polymer like polyethylene that sticks around for a thousand years is not all that different in practice from a fluoropolymer that will stick around for a million years. If they're not recycled they go to landfill.
Maybe more to the point, I'd much prefer to contaminate the environment with inert chemicals with a million year lifespan than with toxic or bio-accumulating chemicals with a thousand year lifespan, and the good news is that the longevity of fluoropolymers is due to their total lack of reactivity.
And just as with polyethylene, additives like plasticizers and various other components added for processing can be a big issue. They used to use pfoa for helping process Teflon. Who knows what they use now.
It’s probably unwise to be overly trusting.
So rejoice in well-funded, status-posturing, subsidizing rubes!
"Yeah man, the latest AI NFT food delivery app plugin is totally waterproof"
For cycling, I’ve been using the Rapha Shadow range [0] which has been brilliant. It is on the expensive side but definitely worth it.
I guess people might not trust anything active in a situation where getting wet could be dangerous, but in a city it seems like it could be a cool way to make waterproofing that never wears out as long as the air pump works.
My personal opinion is the price isn't worth it. For wet weather I'll stick with wellies, good socks and a poncho.
Sandals and mesh sneakers are better in terms of heat, but not an option for many hiking trails (ymmv). And obviously not water proof.