How to Shorten Your Sleeping Pad in 6 Steps

Why Risk It?

Why should you shorten your inflatable sleeping pad? I don’t have a good answer for this. I just don’t want or need an extra 2 feet of sleeping pad to inflate and carry with me.

Disclaimer: if you do this, you will void your warranty, and if you mess it up, you have a big useless lump of fabric

Alright, you’ve done your research and you’ve found that the “perfect pad” just doesn’t exist. If you’re like me, an extremely small back-sleeper and cold at night, you will likely encounter the following struggles finding the perfect sleeping pad: its too narrow, so your arms flop off the sides; it’s far longer than necessary; or, it’s not warm enough. Where is the Short, Wide r>5 sleeping pad?

I don’t think it exists. So, here’s how I took matters into my own hands, in 6 easy steps.

1. Measure

Removing almost 2 feet from the pad

First, fully inflate that expensive sleeping pad of yours, grab a sharpie, lay down on it, and lightly mark which baffle your heels come to.

Count 2 baffles down from your mark, and make another mark. In the event of a mistake, allotting extra room allows for you to try again.

2. Cut

Cut slightly below a baffle line

Make a straight cut with scissors just short of the third baffle line from your heel mark. Now, you should have 2 pieces of sleeping pad. Your good one, and the scrap end piece.

3. Practice Steps 4 and 5

On the bit of scrap sleeping pad, practice steps 4 and 5.

4. Trim the Insulation

Cutting excess foil and fabric

Fold back the outer layers (top and bottom) of the sleeping pad, exposing as much of the insulation as you can. Next, if you have a Thermarest NeoAir, you will find foil and fabric, remove as much of it with your scissors as you can, without cutting into the next baffle. If you have a Nemo Tensor, you will also find a thin filament of plastic in addition to the foil and fabric; Keep this plastic layer.

Trimmed insulation

5. Heat Seal (Iron)

Pressing the iron in sections, middle out

Remove any water from your household iron so it has no opportunity to steam. Then, plug your iron in and crank the heat as high as it can go. While the iron warms, unfold the top and bottom layer of the mat and ensure it lies perfectly flat on an iron safe surface, face up. Once the iron is hot, lightly tap the middle of the pad, pulling the iron off the edge (I do not recommend running it along the edge initially, as I have found it makes creases). Repeat until the entire edge has been tamped down. Once this is done, you can freely run the iron across the edge to ensure a good heat seal, working the corners especially.

6. Inspect and Test

Successful weight bearing. No leaks!

Once completed you should have a seal that looks very similar, if not identical, to the other edges of the sleeping pad. To test the quality of the seal, fully inflate the pad and place weights on it overnight.


How far will you go to shave some weight?

Apparently, I’ll go as far as to sacrifice the longevity of my gear, while refusing to sacrifice my quality of sleep. This isn’t for everybody, but it is for me.

Bonus goat fact: the trimmed Thermarest NeoAir Xtherm Max Large is still heavier than the Xtherm long mummy style.

Go nuts!

-A Nameless Mountain Goat

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Comments 5

  • Cassandra : Sep 9th

    Okay Sprite, before I cut my $250 sleeping pad, how has this held up? I’m in the same boat sleep-wise and having an extra 12+ inches of pad seems dumb lol.

    • Sprite : Sep 11th

      Hey!! It’s held up so far! If you go ahead, just remember the warranty will no longer be valid. However, I’ve done this to a few pads since and they’ve all been good.

      • Cassandra : Sep 14th

        Thanks so much for your reply, I feel much better now! If/when I gather up my courage I’ll let you know how it turns out. 😀

      • Cassandra : Nov 22nd

        Hi Sprite, just wanted to update you. I shortened my Xtherm and am about to do the same to my Xlite. Thanks so much for this awesome tutorial!


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