Mattresses / sleeping pads

Are the insulated / high R-value matts ever too warm?

My foam mattress at home is a bit too warm in summer, and I'm wondering if the warmer hiking mattresses are the same. It sounds like combining a standard R~3 inflatable mattress with a closed cell foam one in winter might provide the same performance with more versatility?

Herman - that depends on the individual. I am a fairly warm sleeper so I generally only take my Thermarest Ridgerest mattress, R value of 2.4 (if I remember correctly) even in winter. My bag is rated to -10Deg C and I've never really been cold (except in really windy conditions where wind came in at the top of the bag).

My wive once complained of overheating in Rolands cave in June while in her -15 Deg bag, sleeping on an inflatable mattress with an R rating of 5.

The answer to your question is therefore yes, it is possible, but not applicable to all people.

really.. you can't blame the mattress if you sleep in a -15 bag!?

I think the R ratings make a very minimal difference as I have 3 mats of varying thicknesses and can hardly tell any difference. I put it down to marketing yadayada!

I have noticed a huge difference is I sleep on my heavy duty space blanket though. Unlike the mattress it has a larger footprint and forms a protective barrier to cold while also reflecting back warmth. I once had a perfect test scenario that just happened on top of the escarpment in winter - exactly the same tents and make of sleeping bags in both with only our space blankets under us as the difference. We slept nice and warm while the others complained of a really cold night that kept them awake. I was quite amazed at the difference!

I can, as my wife had complained of sleeping cold in the same sleeping bag while using a Thermarest Ridgerest mattress on the previous hike also in winter.

Agreed on your ground cover making a difference - we use Du Ponts Tyvek (a building insulator) and this also works really well in keeping you warm.

Bottom line - utilising a couple of items in your sleeping systems will make you sleeping warmer.

One last thing I noticed for sleeping warmer, is the last meal you eat before going to bed, I mean sleeping bag. A rich, oily, calorie rich meal will keep your body working longer to digest the meal and provide energy to keep you warm. A small meal with a low calorie count will certainly make for a colder night. I tested this out once in winter. For 2 nights straight I only had salad for dinner, and I was freezing! The 3rd night I had a big bowl of pasta and it made a huge difference to how warm I slept. So, sleeping bag, insulation material for your ground cover, sleeping pad/mattress and your evening meal will all influence how warm you sleep. 

There are other factors at play as well, but I'm not going to expand on them as the above are the big ticket items. Other things influencing how hot you sleep would be your health status (if you are sick and battling some sort of virus your body will allocate less energy to keeping you warm and more energy to fight the virus), fitness level (fitter sleeps warmer), altitude, wind etc.

Best thing is to experiment and see what works for you

Thanks guys, useful info. I agree on the space blanket / Tyvek experience, as well as the food. I know people who eat chocolate if they wake up from the cold. The chocolate warms them up enough to go back to sleep. Also works well if someone has mild hypothermia. I have also experienced the difference a space blanket makes - I used a simple Coghlans groundsheet/space blanket from Outdoor Warehouse for many years. Worked really well. I should get one again, unless Tyvek is better, @Riaang?

A year ago I hiked with RiaanG and he let me use a Tyvek sheet of his for the Mweni traverse. It worked well. Seemed to help with heat but also it provided for a cleaner area around oneself and it is also lightweight and very tough. I would definitely use that again. Many plastics like to tear at any folds over a period of time. I suspect Tyvek will take a long time to reach that point. Oh, it also helped keep water at bay in a slightly wet Easter Cave!

A tin of sardines at dinner also does the trick on keeping one warm  

Thanks for the detailed response, Intrepid.

Just to clarify - I am curious because our memory foam mattress on our bed at home can be too warm - haven't had the same problem with my hiking mattress.
I'm thinking of it in a Berg context (as well as the Magaliesberg, Blouberg, etc, which can be much warmer). But by all accounts, it sounds like the R=3 mattresses hit the sweet spot for SA for most people in most conditions

BTW, I usually put my foam mattress under my tent to protect the tent's groundsheet and keep it tidier inside.  It tends to work very well for me and may help reduce the two mattress slipping problem somewhat for tent camping. Won't put an inflatable mattress underneath the tent, of course.

Hi  there,

Has anyone used the First Ascent Ultralight Insulated Mattress? It quotes an R-Value of 3 and I wonder how accurate this value is. 

I have the First Ascent Aero 5.5 and am very happy with it but need a mat with a bit more insulation. It ticks the boxes from a weight, height and packed size perspective but just want to be sure it is warm enough for the berg.

Weight (Kg): 0.465
Designed For Camping, Hiking
Dimensions: 180 X 50 X 3.2cm
R-Rating: 3
Packed Size: 16 X 12cm

Thanks

@admoss... I had one for a year and threw it out yesterday. It is not robust enough and is leaking from the sealed seams and in temps below minus 5 degrees does not insulate. I am going back to my old heavier Thermal Comfort which over the many years has never let me down. There are other light weight, more expensive imported mattresses which are good, This winter is colder than normal and insulation is extremely important in the Berg.