I am sick of packing my 4-season therm-a-rest inside my pack, it takes up way too much room and makes packing the rest of the gear harder... Now that wasn't a problem in the good olde foam matress days!

So, how can i safely pack my therm-a-rest on the outside? I am thinking a long, thin, drysack of sorts...

any recommendations?

Use a rubble sack (10 for a quid from the supermarket). They're well sturdy. Maybe wrap some kind of compression strap or 2 round it.

Or... Get a shiny new rucksack that's a tiny bit bigger than your old one! ;-)

which thermarest have you got?
my prolite 4 packs up nice and small

I have a fat 4-season one made for women... I like it because it is warm and comfortable. I may try the rubble sack thing, do they make long thin dry bags?

They're about 2.5 foot by 1.5 foot. I use them as rucksack liners and as a "hydration pocket" (put my platy in one so when I forget to screw the lid on properly everything else stays dry).

Have a look in your local Tescoburys - measurements should be on the pack.

Depending on your rucksack, you can remove the foam back padding and use the thermarest instead?

Not always ideal, but just another option.

erm when you say rubble sac what exactly are we talking about?

heavy grade bin bags from B&Q

A rubble sack is a big thick bin bag.
For clearing building debris, not for kidnapping Barney.

lol @ ptc*

The Tesco ones are blue - they're the only blue plastic bags that they sell so you can hardly miss them.

http://www.venturesport.co.uk/venturesport_product.asp?parseid=7011

Mountain Equipment do this in various sizes & the one I have (25L) is quite long & thin. Can't give you the dimensions at the mo as it isn't at hand but if you can't find them I'll gladly post them later. I'd say it was probably long enough. Casting my mind back to the packaging that came with it I think these are made by someone else based in the USA but sold by ME - so someone else may also do them. Once the top is secured air can be squeezed out of the thermarest type valve on the side. I use one as a rucsac liner - most of my gear is packed away in it before I strike the tent. It fills 2/3 of my rucsac & the tent is then stuffed down the side. Seems durable & no problems so far.

Thanks for the link Spiritburner. Another excuse to spend some more money!

Goat, I use various thermarests (TR). Sometimes I carry a piece of thin (2-3mm) karrimat type of foam, a little wider that the TR and 1 metre long (comes in metre widths). Weighs about 2-3 ozs. In winter, this goes under my thermarest to provide extra insulation to my torso (especially as I use the lightweight ones with holey foam) and is a backup should the TR get a hole (heaven forbid in very cold conditions as finding the hole would be difficult). In summer, I use a short TR so this thin mat might go under my feet, to prevent getting a wet sleeping bag from condensation off the floor (I use a Nallo, not the best ventilated but otherwise superb).

If I can't get my TR inside the sack (say at the beginning of a trek), I wrap the mat around the rolled-up TR, then put these in a homemade nylon bag (just the right size!), which is usually carried on top of the sac. The extra length of the mat protects the end of the TR, especially in this vulnerable position. I carry the mats inside the pack as soon as I have space, as the mats on top of the sac tend to catch the wind more.

If you wanted to go super-light, you could use the thin mat on its own. It's a really useful thing to carry - and you can lie outside the hut/bothy/tent on it, too.

always keep all stuff in the sack. please dont consider attaching to the outside, firstly its prone to damage, 2nd may fall off, 3 youll worry about it falling off and 4thly it looks shit!

keep it safe!

You could try rolling it without first folding it in half so it's long and thin (I think that's what you had in mind anyway). Measure it up against an orange survival bag, and if it fits cut the bag down as required. Heavy duty polythene should keep it dry and protected against scrapes.

I'd put some kind of compression strap around it and try to fix this under a spare buckle on your pack as insurance against loss.

I use the leg of an old pair of waterproof trousers, cut off and sealed at one end. A relic of my army days, but it works a treat.

If you're going to tote the Therm-a-rest on the outside of your pack, you want to wrap it in something scuff-proof and thorn-proof. I've seen people throw their packs to the ground, only to have their Therm-a-rest punctured on thorny scrub, and I guess the same could happen if you go scratching it past a thorn bush or sharp rock.

I pack mine inside a much smaller pack than most people would use, so in effect I lose even more packing space than someone with a big pack.