It might help to know how tall you are and how many inches you need at the base of the pad for your dog? how big is the dog? I’ve been thinking about the same topic, but I would have my dog sleep next to me – he and I are too large to share a pad!
Summary, based on my experience, if my goal was to share my pad with my dog (and it was a small dog and if I wasn’t 6′ 0″ tall), I’d get one of these evazote pads to put on top of an inflatable like a ne0-air: https://mountainlaureldesigns.com/product/1-4-foam-pad/
Depending on the nature of the underlying pad, you can get the evazote pad from MLD in wider and longer pieces (vs. the Gossamer options) and use the delivered size or cut it down. A 20x40x1/4 inch pad weights 3.3 ounces. I carry one of those all the time. I have several versions in my personal inventory.
The challenge is the underlying pad. If you want to be warmer, the Xtherm is a good option. The long rectangular version is currently advertised at 1lb 7oz. That doesn’t leave much weight allocation to put a protective closed cell foam pad on top for dog claw protection. If you can get by with a Neo Air Xlite with an Evazote on top, you would achieve your weight and R value goals. I have not personally used the Xlite and it will be more puncture / wear prone than the Xtherm. If you can live with a mummy shaped pad, the large Xlite with an evazote on top would meet all the metrics you put forth, but I’m not sure how it would actually function as a dual sleep surface.
I don’t know how a NeoAir surface will do with a dog on it (they can collapse a bit on the edges), but if you put a foam pad on top, it stabilizes things a lot. Plus, the dog can sleep on the foam pad off to the side if desired. In cold conditions I’ll sometimes use a Large Xtherm (mummy shaped or rectangular – makes no difference) and put a 25×80 ridge rest or 25×80 blue foam pad on top. It really stabilizes things – I know that is heavier and bulkier than what you are looking for, thus the suggestion of a smaller 1/4 inch evazote on top.
I’ve heard/read good things about the Nemo Tensor and that might provide a more stable platform for the dog, and it is a bit lighter, leaving more weight allocation for a protective closed cell pad on top. Others who have used both (Tensor vs Neoair) might comment on that. I think Ryan Jordan uses a Tensor?
Warmth usually comes into the equation: My impression is the the Thermarest Xtherm is very warm. When on cold or cooler trips I will often put a closed cell foam pad on top of an Xtherm. Last year when using that combination at about 30 degrees F, I was inexplicably hot while sleeping – my best guess is that it was the pad arrangement. I haven’t had the time or patience to try to do day over day comparisons with my pads, such as switching out pads in similar conditions to confirm that my warmth on that last trip was due to pad configuration.
For reference, I own Xtherms and many other pads in various configurations (that happens with a family of six). I wouldn’t want my dog on my Xtherm due to concern about the nails abrading the fabric – but that’s just me and the Xtherm is reputed to be quite tough so others might be comfortable with that risk.
I have considered using a cut down piece of evazote for my dog. In fact, I normally carry a 20x40x1/4 inch sheet on hikes for use as a sit pad and emergency pad. Despite the relatively low R rating of 1/4 evazote, I find that when laid on a chair outside on a cold day, and sitting on it, the senses of warmth is really quite amazing. I’m sure that pad would be sufficient for my large, furry, English Setter down to 30. I would NOT use it as MY sole insulation.
