Putting sleeping pad inside of the bag?

I looked around the interweb a bit and Big Agnes makes a pump bag similar to the exped , and it appears as though roughly 4 fills of the bag will fill the bed , not only does it save your lungs , but it prevents moisture from your breath degrading the pad insulation and preventing ice from forming on cold camp outs . and you can use it as a stuff sack so it takes up zero extra space and weight close to nothing
http://www.moosejaw.com/moosejaw/sh...x&adtype=pla&gclid=CPaxmMaH1bMCFehDMgodbGwADw

Tie or bungee the bag to the pad. Most sleeping bags have at least one tie down set at the foot (even my $20 off brand). Run some paracord, rope, string, or a bungee from one of the tie downs under the mattress and to the other tie down. If your bag doesn't have any tie downs (more common on rectangular bags), you can see about sacrificing the last inch or so of space at the foot of the bag for a tie down.

I first tried this with my summer weight bag/liner, which is just a thin fleece inner layer with a nylon outer. I toss and turn a ton at night and usually wind up with the bag upside down and off the pad while being twisted in the middle; awkward, considering it's a mummy bag. Just using the foot tiedown was enough to keep the bag put on my Big Agnes mattress. There was a smidgen of shifting at the top end, but it was surprised me how little the bag actually moved with only the foot tied down. It was at least enough to keep me on the mattress and the bag from constricting like a boa.

I haven't tried this with rectangular bags, but traditionally mummy bags have always moved a lot more than rectangular bags in my personal experience.

have a seamstress put a sleeve on the bottom of your current bag, of course sized right for you new pad.

I use a Big agnes summit park and an exped 9 dxl pad,, comfy.

Yeah, that's my approach.

You need the sleeve fairly loose unless it's a very big bag, with the bottom stretched out by the pad the bag can be a bit too snug otherwise.

Makes for a lot more comfort and (maybe undesirable) it's a LOT warmer without heat escaping the bottom of the bag.

Pete

Ha!! Good One!!! That's what I do now. I used to sleep on the mattress until one summer night I just slept on the pad & when it got cool I pulled the bag over like a quilt. I have the insulated pad so sleeping on it kept that side warm & the bag worked very well as a quilt. The bottom of my bag doesn't unzip all the way so my feet are in the bag. Now do that all the time, summer or winter.