Interested if anyone has used the Synmat UL 7 in winter conditions. Was it enough or did you need a thin piece of foam or reflective "blanket" under it for any additional warmth?

-7 C overnight. Had some 1/8" foam from Gossamer (I think) under it. Was warm.

Cheers

Like Roger, I have also used the Synmat UL7 teamed with a 1/8 Gossamer Gear pad and I found this combination plenty warm at -10 C (14F). I'm a middle aged female side sleeper who really feels the cold.

I've also taken my Synmat UL7 down to the low 20s, perhaps high teens (*F), with a 1/4" foam mat underneath and had plenty of insulation from the ground.

I'm not sure if it affects the pad's warmth at all, but I did experience quite a bit of internal condensation inside the mat from blowing it up with my breath given the drastic temp differences between the ambient overnight air temps and my warm breath. Probably will look into some kind of pump sack for cold winter trips in the future.

Nico, give the Schnozzel a look. It's excellent for inflating your Synmat and makes and excellent dry bag for your bag.

Just the Synmat UL7 = not warm enough when the ground is frozen. I can still catch a bit of sleep, but I'm obviously losing heat so I need to roll from one side to the other every 30-60 min.

With a torso sized RidgeRest underneath, nice and toasty at -28 C / -19 F last week.

I'm fine down to the mid-twenties F. Colder than that and I add a piece of 3/8" foam which also provides insurance if the UL7 springs a leak. Another thumbs up for the pump bag.

+ 1 on all Dondo's comments. mirrors my experience.

Add RR / RR Deluxe and sleep comfy at -25 C/-30 C.

Right now testing Down Mat 7 UL = -12 C and v. comfortable (600 g 860 CUIN down bag).