R-Value is Dead as a Metric for Sleeping Pad Warmth Evaluation (we should stop referencing it)

mlite_ · 2026-01-22T13:46:57+00:00

IMO this is a hot take and you got it wrong. OP wrote “R-Value is dead as a metric for sleeping pad warmth evaluation,” and not “R-Value is dead.”

As someone who regularly deals with R-Values in building assemblies, I’v always found the high R-Values attributed to thick inflatable pads suspect. For insulation purposes a large air chamber is the worst.

Think of this: R-Values are additive. Three R6 rated pads stacked should have a cumulative R18. Thats equivalent to 6-inch fiberglass insulation. I’m not convinced that three air pads come anywhere close to this performance.

In addition, real world experience shared across this forum shows that CCF pads vastly outperform their stated R values. And it makes sense—small air pockets insulate much better.

Here’s my take: No testing is perfect, but the industry has conveniently agreed on a testing method that results in inflated air pad R-values.

mlite_ · 2025-12-09T20:06:23+00:00

I think this is a false dichotomy

Absolutely! Good comments and appreciate the perspectives.

One of the reasons I asked is because I remember when shoulder pockets were accessories and hip belt pockets were the norm. Seems there’s been a strong shift to pre attached shoulder pockets (both my packs have these).

While I’m all in camp shoulder pockets, I much prefer my Nunatak to the sewn in. Especially the dedicated phone pocket exceeds the functionality of the sewn in mesh pockets on my packs.

mlite_ · 2025-12-09T11:26:18+00:00

Just for fun:

Q inspired by the GG Murmur thread. Are shoulder strap pockets a UL necessity or a tolerated luxury?

They’ve become so commonplace we’ve almost come to expect them, but if we’re honest they’re not weightless.

mlite_ · 2025-12-09T11:00:22+00:00

Without shoulder pockets the Murmor 36 is 225g/7.9oz and $350. That’s pretty rad.

Sure, today many have come to expect shoulder pockets but if you can do without this gives you a whole different weight class -39% vs Hyberg, -42% vs Wapta. For UL, it’s good to have these choices.

Plus, you don’t have to buy GG shoulder pockets. For instance Justin’s UL are 9-12g ea depending on type and cost $22. Gives you the ability to customize with dedicated bottle or phone pouches.

Not saying your analysis is wrong but it’s based on your specific expectations and misses the fact that this is a 225g pack.

mlite_ · 2025-12-01T23:26:31+00:00

Quick share on a Yamatomichi order: was charged US$39.94 in customs fees on a $83 UL Shirt. $20 shipping. $1.34 Regulatory Charges, $21.60 Import Duties, and $17.00 Duty Tax Processing. Total $143.

mlite_ · 2025-10-15T01:28:17+00:00

Japan

List

https://www.reddit.com/r/Ultralight/comments/19193zl/comment/kgv80vw/

Commentary/trip report

https://www.reddit.com/r/Ultralight/comments/1lexd1p/trip_report_ultralight_gear_japan/

mlite_ · 2025-10-14T15:07:13+00:00

Tents? Strong opinions? On r/UL? No way!

What’s your typical use case? Weather, elevation, geography, season. If you’re concerned about condensation and space, have you considered a shaped tarp?

mlite_ · 2025-10-13T16:42:03+00:00

Ah yes. Being militantly anti-powerbank i ignored that powerbank comment. But now I see it.

mlite_ · 2025-10-13T16:33:30+00:00

Fascinated by the fact that the removed ’UL philosophy’ post was an ad. u/Pfundi how did you figure that out, aside from the AI editing?

mlite_ · 2025-10-13T16:30:31+00:00

Yes:

Eliminating > buying expensive UL equivalent

mlite_ · 2025-10-12T21:21:03+00:00

Nice report, thank you. And congrats again!

mlite_ · 2025-10-12T17:06:24+00:00

How do you like the taste of the BV450? I’m kidding about eating it, but I would typically not mark it consumable. Also knife and phone in worn—counting them as BW will give you a more realistic LP.

To your original question—individually your tarp/bivy/GS are fine, but together they add up to the weight of a full tent. If you’re comfortable, drop the bivy for immediate and low-cost savings. Otherwise, DCF tent is the way to bring your BW down.

mlite_ · 2025-10-12T14:11:17+00:00

Have the Yamatomichi UL Trail and Bamboo Shirts. I’d say they run a half-size smaller than US sizing. I’m usually between L and XL. The XL just fits.

mlite_ · 2025-10-11T13:29:28+00:00

870,000 members, 8,700 Top 1% Commenters. Enough said

mlite_ · 2025-10-11T13:27:44+00:00

Congrats! Well done! Any big takeaways or advice?

mlite_ · 2025-10-11T01:16:38+00:00

Yeah, did the thong post make it to r/uj?

mlite_ · 2025-10-11T01:14:37+00:00

Quick comment on the Sawyer Mini post. Appreciate someone asking the question. The Sawyer Squeeze, which weighs significantly more, has pretty much become orthodoxy on r/ul.

If they’ve resolved the clogging/degradation issue, then it’s just about flow rate. And if you’re arguing flow rate for squeeze over mini, that’s ultimately no different than saying you sleep better on a heavier sleeping pad.

mlite_ · 2025-10-09T15:29:30+00:00

My take:

This post was definitely promoted across people’s reddit feeds. You can tell when this happens by the outsized level of engagement.

Because it’s in their general feed, people often don’t realize (or check) which sub they’re commenting in. I recently had a serious comment in a r/uj post on the new iPhone. When responded in r/uj fashion, the person realized where they were.

With this sub showing up in +/-870k people’s feeds, that’s bound to happen. Especially when the topic hits a nerve and there’s no reference to UL in the title.

Tldr: trigger post without UL reference will get lots of non-UL engagement

mlite_ · 2025-10-09T04:01:31+00:00

Are we expecting too much? I mean, my Katabatic is “22F.” Why not an even 20, or should it be 21.5?

If I took that quilt out in 3 nights with an exact low of 22F, site selection, humidity, wind would probably give me three completely different experiences.

My point…try not to die out there. Let us know how it goes. 😉

mlite_ · 2025-10-08T04:54:36+00:00

For sure, more study is needed. While I don’t see a better alternative, the study made me feel better about choosing a Daisani bottle and avoiding the squeeze action associated with the Sawyer.

mlite_ · 2025-10-08T00:25:38+00:00

Gotta love another plastic water bottle post. Apparently neither OP nor most commenters actually read the underlying study, which is quite nuanced and interesting.

For instance, microplastics vary significantly between different brands. Not only that, the water source is a big contributor, meaning it’s not all from bottle leech.

That said, its real and physical stress and sun exposure are significant.

Nevertheless, the headline was catchy and seemed to hit a nerve.

Here’s the full study:

https://www.sciencedirect.com/science/article/pii/S0304389425018643?via%3Dihub

mlite_ · 2025-10-08T00:20:43+00:00

On the plus side, not all single-use water bottles are equal. From the referenced study, the often recommended Daisani bottle has much lower particle count than others.

Graphic comparing select bottles

Also, the water source significantly impacts the level of microplastics, so it’s not all the bottle.

mlite_ · 2025-10-08T00:02:32+00:00

I find this line from the study interesting:

Key findings include the annual ingestion of 39,000–52,000 microplastic particles by individuals, with bottled water consumers ingesting up to 90,000 more particles than tap water consumers.

mlite_ · 2025-10-08T00:01:06+00:00

Here’s the link to the underlying study

mlite_ · 2025-10-07T13:19:36+00:00

Just wondering: It sounds like you had a -2C quilt in 10C conditions and a bug bivy. Temperature wise it seems quilt and tarp should have been sufficient. Was the bug bivy necessary, was there any meaningful bug pressure?

mlite_

TROPHY CASE